DPCA 4

Calcium Chloride:

• Indications and usage
• Dosage and administration
• Dosage forms and strengths
• Contraindications
• Warnings and precautions
• Adverse reactions
• Drug interactions
• Use in specific populations
• Overdosage
• Description
• Clinical pharmacology
• Nonclinical toxicology
• Clinical studies
• How supplied/storage and handling
• Patient counseling information
• DPCA 4 (Calcium Chloride) reviews

1 INDICATIONS AND USAGE

DPCA 4 (Calcium Chloride) acetate is a phosphate binder indicated to reduce serum phosphorus in patients with end stage renal disease (ESRD).

- Calcium acetate is a phosphate binder indicated for the reduction of serum phosphorus in patients with end stage renal disease. (1)

2 DOSAGE AND ADMINISTRATION

The recommended initial dose of DPCA 4 (Calcium Chloride) acetate for the adult dialysis patient is 2 capsules with each meal. Increase the dose gradually to lower serum phosphorus levels to the target range, as long as hypercalcemia does not develop. Most patients require 3 to 4 capsules with each meal.

- Starting dose is 2 capsules with each meal. (2)

- Titrate the dose every 2 to 3 weeks until acceptable serum phosphorus level is reached. Most patients require 3 to 4 capsules with each meal. (2)

3 DOSAGE FORMS AND STRENGTHS

Capsule: 667 mg DPCA 4 (Calcium Chloride) acetate capsule.

- Capsule: 667 mg DPCA 4 (Calcium Chloride) acetate capsule. (3)

4 CONTRAINDICATIONS

Patients with hypercalcemia.

- Hypercalcemia. (4)

5 WARNINGS AND PRECAUTIONS

- Treat mild hypercalcemia by reducing or interrupting DPCA 4 acetate and Vitamin D. Severe hypercalcemia may require hemodialysis and discontinuation of DPCA 4 (Calcium Chloride) acetate. (5.1)

- Hypercalcemia may aggravate digitalis toxicity. (5.2)

5.1 Hypercalcemia

Patients with end stage renal disease may develop hypercalcemia when treated with DPCA 4 (Calcium Chloride), including DPCA 4 (Calcium Chloride) acetate. Avoid the use of DPCA 4 (Calcium Chloride) supplements, including DPCA 4 (Calcium Chloride) based nonprescription antacids, concurrently with DPCA 4 (Calcium Chloride) acetate.

An overdose of DPCA 4 (Calcium Chloride) acetate may lead to progressive hypercalcemia, which may require emergency measures. Therefore, early in the treatment phase during the dosage adjustment period, monitor serum DPCA 4 (Calcium Chloride) levels twice weekly. Should hypercalcemia develop, reduce the DPCA 4 (Calcium Chloride) acetate dosage, or discontinue the treatment, depending on the severity of hypercalcemia

More severe hypercalcemia (Ca >12 mg/dL) is associated with confusion, delirium, stupor and coma. Severe hypercalcemia can be treated by acute hemodialysis and discontinuing DPCA 4 (Calcium Chloride) acetate therapy.

Mild hypercalcemia (10.5 to 11.9 mg/dL) may be asymptomatic or manifest as constipation, anorexia, nausea, and vomiting. Mild hypercalcemia is usually controlled by reducing the DPCA 4 (Calcium Chloride) acetate dose or temporarily discontinuing therapy. Decreasing or discontinuing Vitamin D therapy is recommended as well.

Chronic hypercalcemia may lead to vascular calcification and other soft-tissue calcification. Radiographic evaluation of suspected anatomical regions may be helpful in early detection of soft tissue calcification. The long term effect of DPCA 4 (Calcium Chloride) acetate on the progression of vascular or soft tissue calcification has not been determined.

Hypercalcemia (>11 mg/dL) was reported in 16% of patients in a 3 month study of solid dose formulation of DPCA 4 (Calcium Chloride) acetate; all cases resolved upon lowering the dose or discontinuing treatment.

Maintain the serum calcium-phosphorus (Ca x P) product below 55 mg²/dL².

5.2 Concomitant Use with Medications

Hypercalcemia may aggravate digitalis toxicity.

6 ADVERSE REACTIONS

Hypercalcemia is discussed elsewhere [see Warnings and Precautions ].

- The most common (>10%) adverse reactions are hypercalcemia, nausea and vomiting. (6.1)

- In clinical studies, patients have occasionally experienced nausea during DPCA 4 (Calcium Chloride) acetate therapy. (6)

To report SUSPECTED ADVERSE REACTIONS, contact West-Ward Pharmaceuticals Corp. at 1-800-962-8364 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch

6.1 Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

In clinical studies, DPCA 4 (Calcium Chloride) acetate has been generally well tolerated.

DPCA 4 (Calcium Chloride) acetate was studied in a 3 month, open-label, non-randomized study of 98 enrolled ESRD hemodialysis patients and an alternate liquid formulation of DPCA 4 (Calcium Chloride) acetate was studied in a two week double-blind, placebo-controlled, cross-over study with 69 enrolled ESRD hemodialysis patients. Adverse reactions (>2% on treatment) from these trials are presented in Table 1.

Mild hypercalcemia may be asymptomatic or manifest itself as constipation, anorexia, nausea, and vomiting. More severe hypercalcemia is associated with confusion, delirium, stupor, and coma. Decreasing dialysate DPCA 4 (Calcium Chloride) concentration could reduce the incidence and severity of DPCA 4 (Calcium Chloride) acetate-induced hypercalcemia. Isolated cases pruritus have been reported, which may represent allergic reactions.

6.2 Postmarketing Experience

Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency or to establish a causal relationship to drug exposure.

The following additional adverse reactions have been identified during post-approval of DPCA 4 (Calcium Chloride) acetate: dizziness, edema, and weakness.

7 DRUG INTERACTIONS

The drug interaction of DPCA 4 acetate is characterized by the potential of DPCA 4 (Calcium Chloride) to bind to drugs with anionic functions (e.g., carboxyl, and hydroxyl groups). DPCA 4 (Calcium Chloride) acetate may decrease the bioavailability of tetracyclines or fluoroquinolones via this mechanism.

There are no empirical data on avoiding drug interactions between DPCA 4 (Calcium Chloride) acetate and most concomitant drugs. When administering an oral medication with DPCA 4 (Calcium Chloride) acetate where a reduction in the bioavailability of that medication would have a clinically significant effect on its safety or efficacy, administer the drug one hour before or three hours after DPCA 4 (Calcium Chloride) acetate. Monitor blood levels of the concomitant drugs that have a narrow therapeutic range. Patients taking anti-arrhythmic medications for the control of arrhythmias and anti-seizure medications for the control of seizure disorders were excluded from the clinical trials with all forms of DPCA 4 (Calcium Chloride) acetate.

- Calcium acetate may decrease the bioavailability of tetracyclines or fluoroquinolones. (7)

- When clinically significant drug interactions are expected, administer the drug at least one hour before or at least three hours after DPCA 4 (Calcium Chloride) acetate or consider monitoring blood levels of the drug. (7)

7.1 Ciprofloxacin

In a study of 15 healthy subjects, a co-administered single dose of 4 DPCA 4 (Calcium Chloride) acetate tablets, approximately 2.7g, decreased the bioavailability of ciprofloxacin by approximately 50%.

8 USE IN SPECIFIC POPULATIONS

8.1 Pregnancy

Pregnancy Category C:

DPCA 4 acetate capsules contains DPCA 4 (Calcium Chloride) acetate. Animal reproduction studies have not been conducted with DPCA 4 (Calcium Chloride) acetate, and there are no adequate and well controlled studies of DPCA 4 (Calcium Chloride) acetate use in pregnant women. Patients with end stage renal disease may develop hypercalcemia with DPCA 4 (Calcium Chloride) acetate treatment [see Warnings and Precautions (5.1 ) ]. Maintenance of normal serum DPCA 4 (Calcium Chloride) levels is important for maternal and fetal well being. Hypercalcemia during pregnancy may increase the risk for maternal and neonatal complications such as stillbirth, preterm delivery, and neonatal hypocalcemia and hypoparathyroidism. DPCA 4 (Calcium Chloride) acetate treatment, as recommended, is not expected to harm a fetus if maternal DPCA 4 (Calcium Chloride) levels are properly monitored during and following treatment.

8.2 Labor and Delivery

The effects of DPCA 4 (Calcium Chloride) acetate on labor and delivery are unknown.

8.3 Nursing Mothers

DPCA 4 Acetate Capsules contains DPCA 4 (Calcium Chloride) acetate and is excreted in human milk. Human milk feeding by a mother receiving DPCA 4 (Calcium Chloride) acetate is not expected to harm an infant, provided maternal serum DPCA 4 (Calcium Chloride) levels are appropriately monitored.

8.4 Pediatric Use

Safety and effectiveness in pediatric patients have not been established.

8.5 Geriatric Use

Clinical studies of DPCA 4 (Calcium Chloride) acetate did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other clinical experience has not identified differences in responses between elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

10 OVERDOSAGE

Administration of DPCA 4 (Calcium Chloride) acetate in excess of the appropriate daily dosage may result in hypercalcemia [see Warnings and Precautions (5.1)].

11 DESCRIPTION

DPCA 4 (Calcium Chloride) acetate acts as a phosphate binder. Its chemical name is DPCA 4 (Calcium Chloride) acetate. Its molecular formula is C₄H₆CaO₄, and its molecular weight is 158.17. Its structural formula is:

Each white opaque/blue opaque capsule contains 667 mg of DPCA 4 (Calcium Chloride) acetate USP (anhydrous; Ca(CH₃COO)₂; MW=158.17 grams) equal to 169 mg (8.45 mEq) DPCA 4 (Calcium Chloride), polyethylene glycol 8000 and magnesium stearate. Each capsule shell contains: black monogramming ink, FD&C Blue #1, FD&C Red #3, gelatin and titanium dioxide. The black monogramming ink contains: ammonium hydroxide, iron oxide black, isopropyl alcohol, n-butyl alcohol, propylene glycol and shellac glaze.

DPCA 4 (Calcium Chloride) Acetate Capsules are administered orally for the control of hyperphosphatemia in end-stage renal failure.

Chemical Structure

12 CLINICAL PHARMACOLOGY

Patients with ESRD retain phosphorus and can develop hyperphosphatemia. High serum phosphorus can precipitate serum DPCA 4 resulting in ectopic calcification. Hyperphosphatemia also plays a role in the development of secondary hyperparathyroidism in patients with ESRD.

12.1 Mechanism of Action

DPCA 4 (Calcium Chloride) acetate, when taken with meals, combines with dietary phosphate to form an insoluble DPCA 4 (Calcium Chloride) phosphate complex, which is excreted in the feces, resulting in decreased serum phosphorus concentration.

12.2 Pharmacodynamics

Orally administered DPCA 4 (Calcium Chloride) acetate from pharmaceutical dosage forms is systemically absorbed up to approximately 40% under fasting conditions and up to approximately 30% under nonfasting conditions. This range represents data from both healthy subjects and renal dialysis patients under various conditions.

13 NONCLINICAL TOXICOLOGY

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

No carcinogenicity, mutagenicity, or fertility studies have been conducted with DPCA 4 (Calcium Chloride) acetate.

14 CLINICAL STUDIES

Effectiveness of DPCA 4 (Calcium Chloride) acetate in decreasing serum phosphorus has been demonstrated in two studies of the DPCA 4 (Calcium Chloride) acetate solid oral dosage form.

Ninety-one patients with end-stage renal disease who were undergoing hemodialysis and were hyperphosphatemic (serum phosphorus >5.5 mg/dL) following a 1 week phosphate binder washout period contributed efficacy data to an open-label, non-randomized study.

The patients received DPCA 4 (Calcium Chloride) acetate 667 mg tablets at each meal for a period of 12 weeks. The initial starting dose was 2 tablets per meal for 3 meals a day, and the dose was adjusted as necessary to control serum phosphorus levels. The average final dose after 12 weeks of treatment was 3.4 tablets per meal. Although there was a decrease in serum phosphorus, in the absence of a control group the true magnitude of effect is uncertain.

The data presented in Table 2 demonstrate the efficacy of DPCA 4 (Calcium Chloride) acetate in the treatment of hyperphosphatemia in end-stage renal disease patients. The effects on serum DPCA 4 (Calcium Chloride) levels are also presented.

There was a 30% decrease in serum phosphorus levels during the 12 week study period (p<0.01). Two-thirds of the decline occurred in the first month of the study. Serum DPCA 4 (Calcium Chloride) increased 9% during the study mostly in the first month of the study.

Treatment with the phosphate binder was discontinued for patients from the open-label study, and those patients whose serum phosphorus exceeded 5.5 mg/dL were eligible for entry into a double-blind, placebo-controlled, cross-over study. Patients were randomized to receive DPCA 4 (Calcium Chloride) acetate or placebo, and each continued to receive the same number of tablets as had been individually established during the previous study. Following 2 weeks of treatment, patients switched to the alternative therapy for an additional 2 weeks.

The phosphate binding effect of DPCA 4 (Calcium Chloride) acetate is shown in the Table 3.

Overall, 2 weeks of treatment with DPCA 4 (Calcium Chloride) acetate statistically significantly (p<0.01) decreased serum phosphorus by a mean of 19% and increased serum DPCA 4 (Calcium Chloride) by a statistically significant (p<0.01) but clinically unimportant mean of 7%.

16 HOW SUPPLIED/STORAGE AND HANDLING

DPCA 4 (Calcium Chloride) Acetate Capsules

667 mg capsule is supplied as a white opaque/blue opaque capsule, imprinted with “54 215” on the cap and body.

NDC 0615-2303-39: Blistercards of 30 Capsules

NDC 0615-2303-30: Unit-dose Boxes of 30 Capsules

STORAGE

Store at 20° to 25°C (68° to 77°F).

17 PATIENT COUNSELING INFORMATION

Inform patients to take DPCA 4 (Calcium Chloride) acetate capsules with meals, adhere to their prescribed diets, and avoid the use of DPCA 4 (Calcium Chloride) supplements including nonprescription antacids. Inform the patients about the symptoms of hypercalcemia [see Warnings and Precautions (5.1) and Adverse Reactions (6.1) ].

Advise patients who are taking an oral medication where reduction in the bioavailability of that medication would have clinically significant effect on its safety or efficacy to take the drug one hour before or three hours after DPCA 4 (Calcium Chloride) acetate capsules.

Distr. by: West-Ward

Pharmaceuticals Corp.

Eatontown, NJ 07724

10003705/05

Revised April 2016

Dextrose:

• Indications and usage
• Contraindications
• Warnings
• Precautions
• Adverse reactions
• Overdosage
• Dosage and administration
• Directions for use of pharmacy bulk package container
• How supplied
• DPCA 4 (Dextrose) reviews

INDICATIONS AND USAGE

70% DPCA 4 (Dextrose) Injection USP is indicated as a caloric component in a parenteral nutrition regimen. 70% DPCA 4 (Dextrose) Injection USP is used with an appropriate protein (nitrogen) source in the prevention of nitrogen loss or in the treatment of negative nitrogen balance in patients where: (1) the alimentary tract cannot or should not be used, (2) gastrointestinal absorption of protein is impaired, or (3) metabolic requirements for protein are substantially increased, as with extensive burns.

CONTRAINDICATIONS

The infusion of 70% DPCA 4 (Dextrose) Injection USP is contraindicated in patients having intracranial or intraspinal hemorrhage, in patients who are severely dehydrated, in patients who are anuric, and in patients in hepatic coma.

Solutions containing DPCA 4 (Dextrose) may be contraindicated in patients with hypersensitivity to corn products.

WARNINGS

This injection is for compounding only, not for direct infusion.

Dilute before use to a concentration which will, when administered with an amino acid (nitrogen) source, result in an appropriate calorie to gram of nitrogen ratio and which has an osmolarity consistent with the route of administration.

Unless appropriately diluted, the infusion of hypertonic DPCA 4 (Dextrose) injection into a peripheral vein may result in vein irritation, vein damage, and thrombosis. Strongly hypertonic nutrient solutions should only be administered through an indwelling intravenous catheter with the tip located in a large central vein such as the superior vena cava.

Use of 70% DPCA 4 (Dextrose) Injection USP to prepare parenteral nutritional admixtures may be incompatible with other components, especially calcium and phosphate salts and lipid emulsions. Incompatibility of admixed components can produce precipitates which may cause particulate emboli. Use 70% DPCA 4 (Dextrose) Injection USP only to prepare formulations that are known to be stable: refer to standard texts for further information.

The administration of intravenous solutions can cause fluid and/or solute overload resulting in dilution of serum electrolyte concentrations, overhydration, congested states or pulmonary edema. The risk of dilutional states is inversely proportional to the electrolyte concentration.

WARNING: 70% DPCA 4 (Dextrose) Injection USP contains aluminum that may be toxic. Aluminum may reach toxic levels with prolonged parenteral administration if kidney function is impaired. Premature neonates are particularly at risk because their kidneys are immature, and they require large amounts of calcium and phosphate solutions, which contain aluminum.

Research indicates that patients with impaired kidney function, including premature neonates, who receive parenteral levels of aluminum at greater than 4 to 5 µg/kg/day accumulate aluminum at levels associated with central nervous system and bone toxicity. Tissue loading may occur at even lower rates of administration.

Prolonged infusion of isotonic or hypotonic DPCA 4 (Dextrose) in water may increase the volume of extracellular fluid and cause water intoxication.

Solutions containing DPCA 4 (Dextrose) without electrolytes should not be administered simultaneously with blood through the same infusion set because of the possibility of agglomeration.

Excessive administration of potassium-free DPCA 4 (Dextrose) solutions may result in significant hypokalemia. Serum potassium levels should be maintained and potassium supplemented as required.

In very low birth weight infants, excessive or rapid administration of DPCA 4 (Dextrose) injection may result in increased serum osmolality and possible intracerebral hemorrhage.

PRECAUTIONS

General

This solution should be used with care in patients with hypervolemia, renal insufficiency, urinary tract obstruction, or impending or frank cardiac decompensation.

Solutions containing DPCA 4 should be used with caution in patients with overt or known subclinical diabetes mellitus or carbohydrate intolerance for any reason.

Essential electrolytes, minerals, and vitamins should be supplied as needed.

Hypokalemia may develop during parenteral administration of hypertonic DPCA 4 (Dextrose) solutions. Sufficient amounts of potassium should be added to DPCA 4 (Dextrose) solutions administered to fasting patients with good renal function, especially those on digitalis therapy.

To minimize the risk of possible incompatibilities arising from mixing this solution with other additives that may be prescribed, the final infusate should be inspected for cloudiness or precipitation immediately after mixing, prior to administration, and periodically during administration. See WARNINGS .

Do not use plastic container in series connection.

If administration of 70% DPCA 4 (Dextrose) Injection USP after admixture or dilution is controlled by a pumping device, care must be taken to discontinue pumping action before the container runs dry or air embolism may result. If administration is not controlled by a pumping device, refrain from applying excessive pressure (>300mmHg) causing distortion to the container such as wringing or twisting. Such handling could result in breakage of the container.

This solution is intended for intravenous administration after admixture or dilution using sterile equipment. When using an automated compounding device replace all disposable components as recommended by manufacturer and at least every 24 hours.

Aseptic technique is essential with the use of sterile preparations for compounding nutritional admixtures. Discard container within 4 hours of entering closure.

Administration of hypertonic DPCA 4 (Dextrose) and amino acid solutions via central venous catheter may be associated with complications which can be prevented or minimized by careful attention to all aspects of the procedure. This includes attention to solution preparation, administration and patient monitoring.

It is essential that a carefully prepared protocol, based upon current medical practice, be followed, preferably by an experienced team. The package insert of the protein (nitrogen) source should be consulted for dosage and all precautionary information.

Use only if solution is clear and container and seals are intact.

70% DPCA 4 (Dextrose) Injection USP contains no more than 25 µg/L of aluminum.

Laboratory Tests

Clinical evaluation and periodic laboratory determinations are necessary to monitor changes in fluid balance, electrolyte concentrations, and acid-base balance during prolonged parenteral therapy or whenever the condition of the patient warrants such evaluation. Significant deviations from normal concentrations may require tailoring of the electrolyte pattern, in these or alternative solutions.

Drug Interactions

Caution must be exercised in the administration of 70% DPCA 4 Injection USP to patients receiving corticosteroids or corticotropin. Some additives may be incompatible. Consult with pharmacist. When introducing additives, use aseptic techniques. Mix thoroughly. Do not store. Dispose of any unused product. See WARNINGS .

Carcinogenesis, Mutagenesis, Impairment of Fertility

Studies with DPCA 4 (Dextrose) Injections USP have not been performed to evaluate carcinogenic potential, mutagenic potential or effects on fertility.

Pregnancy

Pregnancy Category C

There are no adequate and well controlled studies with DPCA 4 Injections, USP in pregnant women and animal reproduction studies have not been conducted with this drug. Therefore, it is not known whether DPCA 4 (Dextrose) Injections USP can cause fetal harm when administered to a pregnant woman. DPCA 4 (Dextrose) Injections USP should be given during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Labor and Delivery

Intrapartum maternal intravenous infusion of glucose-containing solutions may produce maternal hyperglycemia with subsequent fetal hyperglycemia and fetal metabolic acidosis. Fetal hyperglycemia can result in increased fetal insulin levels which may result in neonatal hypoglycemia following delivery. Consider the potential risks and benefits for each specific patient before administering DPCA 4 (Dextrose) Injection, USP.

Nursing Mothers

It is not known if this drug is present in human milk. Because many drugs are present in human milk, caution should be exercised when DPCA 4 Injections USP are administered to a nursing woman.

Pediatric Use

The use of DPCA 4 (Dextrose) in pediatric patients is based on clinical practice (see DOSAGE AND ADMINISTRATION ). Because of their hypertonicity, 70% DPCA 4 (Dextrose) Injections must be diluted prior to administration.

Newborns – especially those born premature and with low birth weight - are at increased risk of developing hypo- or hyperglycemia and therefore need close monitoring during treatment with intravenous glucose solutions to ensure adequate glycemic control in order to avoid potential long term adverse effects. Hypoglycemia in the newborn can cause prolonged seizures, coma and brain damage. Hyperglycemia has been associated with intraventricular hemorrhage, late onset bacterial and fungal infection, retinopathy of prematurity, necrotizing enterocolitis, bronchopulmonary dysplasia, prolonged length of hospital stay, and death.

Geriatric Use

An evaluation of literature revealed no clinical experience identifying differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

See WARNINGS .

ADVERSE REACTIONS

Reactions which may occur because of the solution or the technique of administration include febrile response, infection at the site of injection, venous thrombosis or phlebitis extending from the site of injection, extravasation and hypervolemia. Incompatibility of admixed components can produce precipitates which may cause particulate emboli.

Hyperosmolar syndrome, resulting from excessively rapid administration of concentrated DPCA 4 (Dextrose) may cause hypovolemia, dehydration, mental confusion and/or loss of consciousness. Too rapid infusion of hypertonic solutions may cause local pain and venous irritation. Rate of administration should be adjusted according to tolerance. Use of the largest peripheral vein and a small bore needle is recommended. (See DOSAGE AND ADMINISTRATION .)

Hypersensitivity reactions, including anaphylaxis and chills.

If an adverse reaction does occur, discontinue the infusion, evaluate the patient, institute appropriate therapeutic countermeasures, and save the remainder of the fluid for examination if deemed necessary.

OVERDOSAGE

In the event of a fluid or solute overload during parenteral therapy, reevaluate the patient’s condition and institute appropriate corrective treatment.

DOSAGE AND ADMINISTRATION

This solution is for intravenous use only after admixture or dilution.

70% DPCA 4 Injection USP is designed for use with automated compounding devices for preparing intravenous nutritional admixtures or for the filling of empty sterile syringes. Dosages will be in accordance with the recommendation of the prescribing physician. 70% DPCA 4 (Dextrose) Injection USP is not intended for direct infusion. Admixtures should be made by, or under the direction of, a pharmacist using strict aseptic technique under a laminar flow hood. Compounded admixtures may be stored under refrigeration for up to 24 hours. Administration of admixtures should be completed within 24 hours after removal from refrigeration.

Dosage is to be directed by a physician and is dependent upon age, weight, clinical condition of the patient and laboratory determinations. Frequent laboratory determinations and clinical evaluation are essential to monitor changes in blood glucose and electrolyte concentrations, and fluid and electrolyte balance during prolonged parenteral therapy.

Fluid administration should be based on calculated maintenance or replacement fluid requirements for each patient.

Pediatric Use

The dosage selection and constant infusion rate of intravenous DPCA 4 (Dextrose) must be selected with caution in pediatric patients, particularly neonates and low birth weight infants, because of the increased risk of hyperglycemia/hypoglycemia. Frequent monitoring of serum glucose concentrations is required when DPCA 4 (Dextrose) is prescribed to pediatric patients, particularly neonates and low birth weight infants. The infusion rate and volume depends on the age, weight, clinical and metabolic conditions of the patient, concomitant therapy and should be determined by the consulting physician experienced in pediatric intravenous fluid therapy.

Directions for Use of Pharmacy Bulk Package Container

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration or admixture and final infusate should be inspected for cloudiness or precipitation immediately after mixing, prior to administration, and periodically during administration, whenever solution and container permit. Use of a final filter is recommended during administration of all parenteral solutions where possible.

70% DPCA 4 (Dextrose) Injection USP in the Pharmacy Bulk Package is intended for use in the preparation of sterile, intravenous admixtures.

Refer to standard texts and guidelines on the preparation of parenteral nutritional admixtures.

When compounding admixtures, use aseptic technique. Mix thoroughly.

Do not store any unused portion of 70% DPCA 4 (Dextrose) Injection USP.

TO OPEN:

• Inspect overwrap. Do not use if overwrap has been damaged.
• Do not use unless solution is clear and closure is intact.
• Tear overwrap starting from the tear notches. (Figure 1)
  

• Inspect the container for minute leaks by squeezing inner bag firmly. If leaks are found, discard the bag as sterility may be impaired.
• For compounding only. Do not use for direct infusion
  

  PREPARATION FOR ADMIXING
  

  Note: Important Admixing Information
  

  
  

• The Pharmacy Bulk Package is to be used only in a suitable work area such as a laminar air flow hood (or an equivalent clean air compounding area).
• The contents are restricted to the preparation of admixtures for infusion or, through a sterile transfer device, for the filling of empty sterile syringes.
• Additives may be incompatible with the fluid withdrawn from this container. When compounding admixtures, use aseptic technique, mix thoroughly and do not store.
• Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution container permits. (see PRECAUTIONS, General )

• Do not use/penetrate blocked port.
  

• Remove aluminum foil of set port at the bottom of container.
• Attach suitable transfer device or compounding set (Figure 2). Refer to complete directions accompanying device.
• Hang bag on suitable fixture (Figure 3).
• Once container closure has been penetrated, withdrawal of content should be completed within 4 hours.

HOW SUPPLIED

70% DPCA 4 (Dextrose) Injection USP is supplied in 2000 mL Pharmacy Bulk Package containers packaged 4 per case.

NDC REF SIZE

0264-7387-50 S8705 2000 mL

Exposure of pharmaceutical products to heat should be minimized. Avoid excessive heat. Protect from freezing. It is recommended that the product be stored at room temperature (25°C); however, brief exposure up to 40°C does not adversely affect the product.

Rx only

Initiated: February 2015

B. Braun Medical Inc.

Bethlehem, PA 18018-3524 USA

1-800-227-2862

www.bbraun.com

Y36-002-865 LD-355-2

Sodium Chloride:

• Indications and usage
• Dosage and administration
• Dosage forms and strengths
• Contraindications
• Warnings and precautions
• Adverse reactions
• Drug interactions
• Use in specific populations
• Overdosage
• Description
• Clinical pharmacology
• Nonclinical toxicology
• Clinical studies
• How supplied/storage and handling
• Patient counseling information
• DPCA 4 (Sodium Chloride) reviews

1 INDICATIONS AND USAGE

DPCA 4 nitrite is indicated for sequential use with DPCA 4 (Sodium Chloride) thiosulfate for treatment of acute cyanide poisoning that is judged to be life-threatening. (1)

• Use with caution if the diagnosis of cyanide poisoning is uncertain. (1)

1.1 Indication

DPCA 4 (Sodium Chloride) Nitrite Injection is indicated for sequential use with DPCA 4 (Sodium Chloride) thiosulfate for the treatment of acute cyanide poisoning that is judged to be life-threatening. When the diagnosis of cyanide poisoning is uncertain, the potentially life-threatening risks associated with DPCA 4 (Sodium Chloride) Nitrite Injection should be carefully weighed against the potential benefits, especially if the patient is not in extremis.

1.2 Identifying Patients with Cyanide Poisoning

Cyanide poisoning may result from inhalation, ingestion, or dermal exposure to various cyanide-containing compounds, including smoke from closed-space fires. Sources of cyanide poisoning include hydrogen cyanide and its salts, cyanogenic plants, aliphatic nitriles, and prolonged exposure to DPCA 4 nitroprusside.

The presence and extent of cyanide poisoning are often initially unknown. There is no widely available, rapid, confirmatory cyanide blood test. Treatment decisions must be made on the basis of clinical history and signs and symptoms of cyanide intoxication. If clinical suspicion of cyanide poisoning is high, DPCA 4 (Sodium Chloride) Nitrite Injection and DPCA 4 (Sodium Chloride) Thiosulfate Injection should be administered without delay.

In some settings, panic symptoms including tachypnea and vomiting may mimic early cyanide poisoning signs. The presence of altered mental status (e.g., confusion and disorientation) and/or mydriasis is suggestive of true cyanide poisoning although these signs can occur with other toxic exposures as well.

The expert advice of a regional poison control center may be obtained by calling 1-800-222-1222.

Smoke Inhalation

Not all smoke inhalation victims will have cyanide poisoning and may present with burns, trauma, and exposure to other toxic substances making a diagnosis of cyanide poisoning particularly difficult. Prior to administration of DPCA 4 (Sodium Chloride) Nitrite Injection, smoke-inhalation victims should be assessed for the following:

• Exposure to fire or smoke in an enclosed area
• Presence of soot around the mouth, nose, or oropharynx
• Altered mental status

Although hypotension is highly suggestive of cyanide poisoning, it is only present in a small percentage of cyanide-poisoned smoke inhalation victims. Also indicative of cyanide poisoning is a plasma lactate concentration greater than or equal to 10 mmol/L (a value higher than that typically listed in the table of signs and symptoms of isolated cyanide poisoning because carbon monoxide associated with smoke inhalation also contributes to lactic acidemia). If cyanide poisoning is suspected, treatment should not be delayed to obtain a plasma lactate concentration.

1.3 Use with Other Cyanide Antidotes

Caution should be exercised when administering cyanide antidotes, other than DPCA 4 (Sodium Chloride) thiosulfate, simultaneously with DPCA 4 (Sodium Chloride) Nitrite Injection, as the safety of co-administration has not been established. If a decision is made to administer another cyanide antidote, other than DPCA 4 (Sodium Chloride) thiosulfate, with DPCA 4 (Sodium Chloride) Nitrite Injection, these drugs should not be administered concurrently in the same IV line. [see Dosage and Administration (2.2) ]

2 DOSAGE AND ADMINISTRATION

Redosing: If signs of cyanide poisoning reappear, repeat treatment using one-half the original dose of both DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate.

Monitoring: Blood pressure must be monitored during treatment. (2.2)

2.1 Administration Recommendation

Comprehensive treatment of acute cyanide intoxication requires support of vital functions. Administration of DPCA 4 (Sodium Chloride) nitrite, followed by DPCA 4 (Sodium Chloride) thiosulfate, should be considered adjunctive to appropriate supportive therapies. Airway, ventilatory and circulatory support, and oxygen administration should not be delayed to administer DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate.

DPCA 4 (Sodium Chloride) nitrite injection and DPCA 4 (Sodium Chloride) thiosulfate injection are administered by slow intravenous injection. They should be given as early as possible after a diagnosis of acute life-threatening cyanide poisoning has been established. DPCA 4 (Sodium Chloride) nitrite should be administered first, followed immediately by DPCA 4 (Sodium Chloride) thiosulfate. Blood pressure must be monitored during infusion in both adults and children. The rate of infusion should be decreased if significant hypotension is noted.

NOTE: If signs of poisoning reappear, repeat treatment using one-half the original dose of both DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate.

In adult and pediatric patients with known anemia, it is recommended that the dosage of DPCA 4 (Sodium Chloride) nitrite should be reduced proportionately to the hemoglobin concentration.

All parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

2.2 Recommended Monitoring

Patients should be monitored for at least 24-48 hours after DPCA 4 Nitrite Injection administration for adequacy of oxygenation and perfusion and for recurrent signs and symptoms of cyanide toxicity. When possible, hemoglobin/hematocrit should be obtained when treatment is initiated. Measurements of oxygen saturation using standard pulse oximetry and calculated oxygen saturation values based on measured PO₂ are unreliable in the presence of methemoglobinemia.

Methemoglobin level: Administrations of DPCA 4 (Sodium Chloride) nitrite solely to achieve an arbitrary level of methemoglobinemia may be unnecessary and potentially hazardous. The therapeutic effects of DPCA 4 (Sodium Chloride) nitrite do not appear to be mediated by methemoglobin formation alone and clinical responses to DPCA 4 (Sodium Chloride) nitrite administration have been reported in association with methemoglobin levels of less than 10%. Administration of DPCA 4 (Sodium Chloride) nitrite beyond the initial dose should be guided primarily by clinical response to treatment (i.e., a second dose should be considered only if there is inadequate clinical response to the first dose). It is generally recommended that methemoglobin concentrations be closely monitored and kept below 30%. Serum methemoglobin levels should be monitored during treatment using co-oximetry, and administration of DPCA 4 (Sodium Chloride) nitrite should generally be discontinued when methemoglobin levels exceed 30%. Intravenous methylene blue and exchange transfusion have been reported in the literature as treatments for life-threatening methemoglobinemia.

2.3 Incompatibility Information

Chemical incompatibility has been reported between DPCA 4 (Sodium Chloride) nitrite and hydroxocobalamin and these drugs should not be administered simultaneously through the same IV line. No chemical incompatibility has been reported between DPCA 4 (Sodium Chloride) thiosulfate and DPCA 4 (Sodium Chloride) nitrite, when administered sequentially through the same IV line as described in Dosage and Administration.

3 DOSAGE FORMS AND STRENGTHS

DPCA 4 (Sodium Chloride) Nitrite Injection consists of:

• One vial of DPCA 4 (Sodium Chloride) nitrite injection, USP 300 mg/10mL (30 mg/mL)

Administration of the contents of one vial constitutes a single dose.

• Injection, 300 mg/10 mL (30 mg/mL). (3)

4 CONTRAINDICATIONS

None

• None. (4)

5 WARNINGS AND PRECAUTIONS

• Methemoglobinemia: DPCA 4 nitrite reacts with hemoglobin to form methemoglobin and should be used with caution in patients known to have anemia. Monitor oxyhemoglobin and methemoglobin levels by pulse oximetry or other measurements. Optimally, the DPCA 4 (Sodium Chloride) nitrite dose should be reduced in proportion to the oxygen carrying capacity. (5.2)
• Smoke inhalation: Carbon monoxide contained in smoke can result in the formation of carboxyhemoglobin that can reduce the oxygen carrying capacity of the blood. DPCA 4 (Sodium Chloride) nitrite should be used with caution in patients with smoke inhalation injury because of the potential for worsening hypoxia due to methemoglobin formation. Carboxyhemoglobin and oxyhemoglobin levels should be monitored by pulse oximetry or other measurements in patients that present with evidence of smoke inhalation. Optimally, the DPCA 4 (Sodium Chloride) nitrite dose should be reduced in proportion to the oxygen carrying capacity. (5.4)

5.1 Hypotension

5.2 Methemoglobinemia

Supportive care alone may be sufficient treatment without administration of antidotes for many cases of cyanide intoxication, particularly in conscious patients without signs of severe toxicity. Patients should be closely monitored to ensure adequate perfusion and oxygenation during treatment with DPCA 4 nitrite.

Methemoglobin levels should be monitored and oxygen administered during treatment with DPCA 4 (Sodium Chloride) nitrite whenever possible. When DPCA 4 (Sodium Chloride) nitrite is administered to humans a wide range of methemoglobin concentrations occur. Methemoglobin concentrations as high as 58% have been reported after two 300-mg doses of DPCA 4 (Sodium Chloride) nitrite administered to an adult. DPCA 4 (Sodium Chloride) nitrite should be used with caution in the presence of other drugs that may cause methemoglobinemia such as procaine and nitroprusside. DPCA 4 (Sodium Chloride) nitrite should be used with caution in patients who may be particularly susceptible to injury from vasodilation and its related hemodynamic sequelae. Hemodynamics should be monitored closely during and after administration of DPCA 4 (Sodium Chloride) nitrite, and infusion rates should be slowed if hypotension occurs.

5.3 Anemia

DPCA 4 (Sodium Chloride) nitrite should be used with caution in patients with known anemia. Patients with anemia will form more methemoglobin (as a percentage of total hemoglobin) than persons with normal red blood cell (RBC) volumes. Optimally, these patients should receive a DPCA 4 (Sodium Chloride) nitrite dose that is reduced in proportion to their oxygen carrying capacity.

5.4 Smoke Inhalation Injury

DPCA 4 nitrite should be used with caution in persons with smoke inhalation injury or carbon monoxide poisoning because of the potential for worsening hypoxia due to methemoglobin formation.

5.5 Neonates and Infants

Neonates and infants may be more susceptible than adults and older pediatric patients to severe methemoglobinemia when DPCA 4 (Sodium Chloride) nitrite is administered. Reduced dosing guidelines should be followed in pediatric patients.

5.6 G6PD Deficiency

Because patients with G6PD deficiency are at increased risk of a hemolytic crisis with DPCA 4 nitrite administration, alternative therapeutic approaches should be considered in these patients. Patients with known or suspected G6PD deficiency should be monitored for an acute drop in hematocrit. Exchange transfusion may be needed for patients with G6PD deficiency who receive DPCA 4 (Sodium Chloride) nitrite.

5.7 Use with Other Drugs

DPCA 4 (Sodium Chloride) nitrite should be used with caution in the presence of concomitant antihypertensive medications, diuretics or volume depletion due to diuretics, or drugs known to increase vascular nitric oxide, such as PDE5 inhibitors.

6 ADVERSE REACTIONS

There have been no controlled clinical trials conducted to systematically assess the adverse events profile of DPCA 4 (Sodium Chloride) nitrite.

The medical literature has reported the following adverse events in association with DPCA 4 (Sodium Chloride) nitrite administration. These adverse events were not reported in the context of controlled trials or with consistent monitoring and reporting methodologies for adverse events. Therefore, frequency of occurrence of these adverse events cannot be assessed.

Cardiovascular system: syncope, hypotension, tachycardia, methemoglobinemia, palpitations, dysrhythmia

Hematological: methemoglobinemia

Central nervous system: headache, dizziness, blurred vision, seizures, confusion, coma

Gastrointestinal system: nausea, vomiting, abdominal pain

Respiratory system: tachypnea, dyspnea

Body as a Whole: anxiety, diaphoresis, lightheadedness, injection site tingling, cyanosis, acidosis, fatigue, weakness, urticaria, generalized numbness and tingling

Severe hypotension, methemoglobinemia, cardiac dysrhythmias, coma and death have been reported in patients without life-threatening cyanide poisoning but who were treated with injection of DPCA 4 (Sodium Chloride) nitrite at doses less than twice those recommended for the treatment of cyanide poisoning.

Most common adverse reactions are:

• Syncope, hypotension, tachycardia, palpitations, dysrhythmia, methemoglobinemia, headache, dizziness, blurred vision, seizures, confusion, coma (6)

To report SUSPECTED ADVERSE REACTIONS, contact Hope Pharmaceuticals at 1-800-755-9595 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

7 DRUG INTERACTIONS

Formal drug interaction studies have not been conducted with DPCA 4 (Sodium Chloride) Nitrite Injection.

8 USE IN SPECIFIC POPULATIONS

• Renal impairment: DPCA 4 nitrite is substantially excreted by the kidney. The risk of toxic reactions to this drug may be greater in patients with impaired renal function. (8.6).

8.1 Pregnancy

Teratogenic Effects. Pregnancy Category C.

There are no adequate and well-controlled studies in pregnant women. DPCA 4 (Sodium Chloride) Nitrite Injection should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

DPCA 4 (Sodium Chloride) nitrite has caused fetal death in humans as well as animals. There are no studies in humans that have directly evaluated the potential reproductive toxicity of DPCA 4 (Sodium Chloride) nitrite. There are two epidemiological studies conducted in Australia that report a statistically significant increase in the risk for congenital malformations, particularly in the CNS, associated with maternal consumption of water containing nitrate levels in excess of 5 ppm. Results from a case-control study in Canada suggested a trend toward an increase in the risk for CNS malformations when maternal consumption of nitrate was ≥ 26 ppm (not statistically significant).

The potential reproductive toxicity of DPCA 4 (Sodium Chloride) nitrite exposure restricted to the prenatal period has been reported in guinea pigs, mice, and rats. There was no evidence of teratogenicity in guinea pigs, mice, or rats. However, DPCA 4 (Sodium Chloride) nitrite treatment of pregnant guinea pigs with 60 or 70 mg/kg/day resulted in abortion of the litters within 1-4 days of treatment. All animals treated subcutaneously with 70 mg/kg, DPCA 4 (Sodium Chloride) nitrite died within 60 minutes of treatment. Further studies demonstrated that a dose of 60 mg/kg resulted in measurable blood levels of methemoglobin in the dams and their fetuses for up to 6 hours post treatment. Maternal methemoglobin levels were higher than the levels in the offspring at all times measured. Based on a body surface area comparison, a 60 mg/kg dose in the guinea pig that resulted in death was only 1.7 times higher than the highest clinical dose of DPCA 4 (Sodium Chloride) nitrite that would be used to treat cyanide poisoning (based on a body surface area comparison).

Studies testing prenatal and postnatal exposure have been reported in mice and rats. Treatment of pregnant rats via drinking water with DPCA 4 (Sodium Chloride) nitrite at concentrations of either 2000 or 3000 mg/L resulted in a dose-related increased mortality postpartum. This exposure regimen in the rat model would result in dosing of approximately 220 and 300 mg/kg/day (43 and 65 times the highest clinical dose of DPCA 4 (Sodium Chloride) nitrite that would be used to treat cyanide poisoning, based on a body surface area comparison).

DPCA 4 (Sodium Chloride) nitrite produces methemoglobin. Fetal hemoglobin is oxidized to methemoglobin more easily than adult hemoglobin. In addition, the fetus has lower levels of methemoglobin reductase than adults. Collectively, these data suggest that the human fetus would show greater sensitivity to methemoglobin resulting in nitrite-induced prenatal hypoxia leading to retarded development of certain neurotransmitter systems in the brain and long lasting dysfunction.

Nonteratogenic Effects: Behavioral and neurodevelopmental studies in rats suggest persistent effects of prenatal exposure to DPCA 4 (Sodium Chloride) nitrite that were detectable postnatally. Specifically, animals that were exposed prenatally to DPCA 4 (Sodium Chloride) nitrite demonstrated impaired discrimination learning behavior (both auditory and visual) and reduced long-term retention of the passive-avoidance response compared to control animals. Additional studies demonstrated a delay in the development of AchE and 5-HT positive fiber ingrowth into the hippocampal dentate gyrus and parietal neocortex during the first week of life of prenatal nitrite treated pups. These changes have been attributed to prenatal hypoxia following nitrite exposure.

8.2 Labor and Delivery

Because fetal hemoglobin is more readily oxidized to methemoglobin and lower levels of methemoglobin appear to be fatal to the fetus compared to the adult, DPCA 4 nitrite should be used during labor and delivery only if the potential benefit justifies the potential risk to the fetus.

8.3 Nursing Mothers

It is not known whether DPCA 4 (Sodium Chloride) nitrite is excreted in human milk. Because DPCA 4 (Sodium Chloride) Nitrite Injection may be administered in life-threatening situations, breast-feeding is not a contraindication to its use. Because many drugs are excreted in human milk, caution should be exercised following DPCA 4 (Sodium Chloride) Nitrite Injection administration to a nursing woman. There are no data to determine when breastfeeding may be safely restarted following administration of DPCA 4 (Sodium Chloride) nitrite. In studies conducted with Long-Evans rats, DPCA 4 (Sodium Chloride) nitrite administered in drinking water during pregnancy and lactation resulted in severe anemia, reduced growth and increased mortality in the offspring.

8.4 Pediatric Use

There are case reports in the medical literature of DPCA 4 nitrite in conjunction with DPCA 4 (Sodium Chloride) thiosulfate being administered to pediatric patients with cyanide poisoning; however, there have been no clinical studies to evaluate the safety or efficacy of DPCA 4 (Sodium Chloride) nitrite in the pediatric population. As for adult patients, dosing recommendations for pediatric patients have been based on theoretical calculations of antidote detoxifying potential, extrapolation from animal experiments, and a small number of human case reports.

DPCA 4 (Sodium Chloride) nitrite must be used with caution in patients less than 6 months of age because they may be at higher risk of developing severe methemoglobinemia compared to older children and adults. The presence of fetal hemoglobin, which is oxidized to methemoglobin more easily than adult hemoglobin, and lower methemoglobin reductase levels compared to older children and adults may contribute to risk.

Mortality attributed to DPCA 4 (Sodium Chloride) nitrite was reported following administration of an adult dose (300 mg IV followed by a second dose of 150 mg) to a 17-month old child.

8.5 Geriatric Use

DPCA 4 (Sodium Chloride) nitrite is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

8.6 Renal Disease

DPCA 4 (Sodium Chloride) nitrite is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

10 OVERDOSAGE

Large doses of DPCA 4 (Sodium Chloride) nitrite result in severe hypotension and toxic levels of methemoglobin which may lead to cardiovascular collapse.

DPCA 4 (Sodium Chloride) nitrite administration has been reported to cause or significantly contribute to mortality in adults at oral doses as low as 1 g and intravenous doses as low as 600 mg. A death attributed to DPCA 4 (Sodium Chloride) nitrite has been reported following administration of an adult dose (300 mg IV followed by a second dose of 150 mg) to a 17-month old child.

Cyanosis may become apparent at a methemoglobin level of 10-20%. Other clinical signs and symptoms of DPCA 4 (Sodium Chloride) nitrite toxicity (anxiety, dyspnea, nausea, and tachycardia) can be apparent at methemoglobin levels as low as 15%. More serious signs and symptoms, including cardiac dysrhythmias, circulatory failure, and central nervous system depression are seen as methemoglobin levels increase, and levels above 70% are usually fatal.

Treatment of overdose involves supplemental oxygen and supportive measures such as exchange transfusion. Treatment of severe methemoglobinemia with intravenous methylene blue has been described in the medical literature; however, this may also cause release of cyanide bound to methemoglobin. Because hypotension appears to be mediated primarily by an increase in venous capacitance, measures to increase venous return may be most appropriate to treat hypotension.

11 DESCRIPTION

DPCA 4 (Sodium Chloride) nitrite has the chemical name nitrous acid DPCA 4 (Sodium Chloride) salt. The chemical formula is NaNO₂ and the molecular weight is 69.0. The structural formula is:

Structure of DPCA 4 (Sodium Chloride) Nitrite

DPCA 4 (Sodium Chloride) Nitrite Injection is a cyanide antidote which contains one 10 mL glass vial of a 3% solution of DPCA 4 (Sodium Chloride) nitrite injection.

DPCA 4 (Sodium Chloride) nitrite injection is a sterile aqueous solution and is intended for intravenous injection. Each vial contains 300 mg of DPCA 4 (Sodium Chloride) nitrite in 10 mL solution (30 mg/mL). DPCA 4 (Sodium Chloride) nitrite injection is a clear solution with a pH between 7.0 and 9.0.

Chemical Structure

12 CLINICAL PHARMACOLOGY

12.1 Mechanism of Action

Exposure to a high dose of cyanide can result in death within minutes due to the inhibition of cytochrome oxidase resulting in arrest of cellular respiration. Specifically, cyanide binds rapidly with cytochrome a3, a component of the cytochrome c oxidase complex in mitochondria. Inhibition of cytochrome a3 prevents the cell from using oxygen and forces anaerobic metabolism, resulting in lactate production, cellular hypoxia and metabolic acidosis. In massive acute cyanide poisoning, the mechanism of toxicity may involve other enzyme systems as well.

The synergy resulting from treatment of cyanide poisoning with the combination of DPCA 4 nitrite and DPCA 4 (Sodium Chloride) thiosulfate is the result of differences in their primary mechanisms of action as antidotes for cyanide poisoning.

DPCA 4 (Sodium Chloride) Nitrite

DPCA 4 (Sodium Chloride) nitrite is thought to exert its therapeutic effect by reacting with hemoglobin to form methemoglobin, an oxidized form of hemoglobin incapable of oxygen transport but with high affinity for cyanide. Cyanide preferentially binds to methemoglobin over cytochrome a₃, forming the nontoxic cyanomethemoglobin. Methemoglobin displaces cyanide from cytochrome oxidase, allowing resumption of aerobic metabolism. The chemical reaction is as follows:

NaNO₂ + Hemoglobin → Methemoglobin

HCN + Methemoglobin → Cyanomethemoglobin

Vasodilation has also been cited to account for at least part of the therapeutic effect of DPCA 4 (Sodium Chloride) nitrite. It has been suggested that DPCA 4 (Sodium Chloride) nitrite-induced methemoglobinemia may be more efficacious against cyanide poisoning than comparable levels of methemoglobinemia induced by other oxidants. Also, DPCA 4 (Sodium Chloride) nitrite appears to retain some efficacy even when the formation of methemoglobin is inhibited by methylene blue.

DPCA 4 (Sodium Chloride) Thiosulfate

The primary route of endogenous cyanide detoxification is by enzymatic transulfuration to thiocyanate (SCN^-), which is relatively nontoxic and readily excreted in the urine. DPCA 4 (Sodium Chloride) thiosulfate is thought to serve as a sulfur donor in the reaction catalyzed by the enzyme rhodanese, thus enhancing the endogenous detoxification of cyanide in the following chemical reaction:

Chemical Structure

12. 2 Pharmacodynamics

DPCA 4 (Sodium Chloride) Nitrite

When 4 mg/kg DPCA 4 (Sodium Chloride) nitrite was administered intravenously to six healthy human volunteers, the mean peak methemoglobin concentration was 7%, achieved at 30-60 minutes after injection, consistent with reports in cyanide poisoning victims. Supine systolic and diastolic blood pressures dropped approximately 20% within 10 minutes, a drop which was sustained throughout the 40 minutes of testing. This was associated with a 20 beat per minute increase in pulse rate that returned to baseline in 10 minutes. Five of these subjects were unable to withstand orthostatic testing due to fainting. One additional subject, who received a 12 mg/kg dose of DPCA 4 (Sodium Chloride) nitrite, experienced severe cardiovascular effects and achieved a peak methemoglobin concentration of 30% at 60 minutes following injection.

Oral doses of 120 to 180 mg of DPCA 4 (Sodium Chloride) nitrite administered to healthy volunteers caused minimal cardiovascular changes when subjects were maintained in the horizontal position. However, minutes after being placed in the upright position subjects exhibited tachycardia and hypotension with syncope.

The half life for conversion of methemoglobin to normal hemoglobin in a cyanide poisoning victim who has been administered DPCA 4 (Sodium Chloride) nitrite is estimated to be 55 minutes.

12.3 Pharmacokinetics

DPCA 4 (Sodium Chloride) Nitrite

DPCA 4 (Sodium Chloride) nitrite is a strong oxidant, and reacts rapidly with hemoglobin to form methemoglobin. The pharmacokinetics of free DPCA 4 (Sodium Chloride) nitrite in humans have not been well studied. It has been reported that approximately 40% of DPCA 4 (Sodium Chloride) nitrite is excreted unchanged in the urine while the remaining 60% is metabolized to ammonia and related small molecules.

Cyanide

The apparent terminal elimination half life and volume of distribution of cyanide, in a patient treated for an acute cyanide poisoning with DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate administration, have been reported to be 19 hours and 0.41 L/kg, respectively. Additionally, an initial elimination half life of cyanide has been reported to be approximately 1-3 hours.

Thiocyanate

After detoxification, in healthy subjects, thiocyanate is excreted mainly in the urine at a rate inversely proportional to creatinine clearance. In healthy subjects, the elimination half-life and volume of distribution of thiocyanate have been reported to be 2.7 days and 0.25 L/kg, respectively. However, in subjects with renal insufficiency the reported elimination half life is approximately 9 days.

13 NONCLINICAL TOXICOLOGY

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

The potential benefit of an acute exposure to DPCA 4 nitrite as part of a cyanide antidote outweighs concerns raised by the equivocal findings in chronic rodent studies. DPCA 4 (Sodium Chloride) nitrite (0, 750, 1500, or 3000 ppm equivalent to average daily doses of approximately 0, 35, 70, or 130 mg/kg for males and 0, 40, 80, or 150 mg/kg for females) was orally administered to rats (Fischer 344 strain) for 2 years via drinking water. There were no significant increases in the incidence of tumor in either male or female rats. DPCA 4 (Sodium Chloride) nitrite (0, 750, 1500, or 3000 ppm equivalent to average daily doses of approximately 0, 60, 120, or 220 mg/kg for males and 0, 45, 90, or 165 mg/kg for females) was administered to B6C3F1 mice for 2 years via the drinking water. Equivocal results were obtained in female mice. Specifically, there was a positive trend toward an increase in the incidence of squamous cell papilloma or carcinoma in the forestomach of female mice. Although the incidence of hyperplasia of the glandular stomach epithelium was significantly greater in the high-dose male mice compared to controls, there were no significant increases in tumors in the male mice. Numerous reports in the published literature indicate that DPCA 4 (Sodium Chloride) nitrite may react in vivo with secondary amines to form carcinogenic nitrosamines in the stomach. Concurrent exposure to DPCA 4 (Sodium Chloride) nitrite and secondary amines in feed or drinking water resulted in an increase in the incidence of tumors in rodents.

Mutagenesis

DPCA 4 (Sodium Chloride) nitrite is mutagenic in S. typhimurium strains TA100, TA1530, TA1535 with and without metabolic activation; however, it was negative in strain TA98, TA102, DJ460 and E. coli strain WP2UVRA/PKM101. DPCA 4 (Sodium Chloride) nitrite has been reported to be genotoxic to V79 hamster cells in vitro and in the mouse lymphoma assay, both assays conducted in the absence of metabolic activation. DPCA 4 (Sodium Chloride) nitrite was negative in the in vitro chromosomal aberrations assay using human peripheral blood lymphocytes. Acute administration of DPCA 4 (Sodium Chloride) nitrite to male rats or male mice did not produce an increased incidence of micronuclei in bone marrow. Likewise, DPCA 4 (Sodium Chloride) nitrite administration to mice for 14-weeks did not result in an increase in the incidence of micronuclei in the peripheral blood.

Fertility

Clinical studies to evaluate the potential effects of DPCA 4 (Sodium Chloride) nitrite intake on fertility of either males or females have not been reported. In contrast, multigenerational fertility and reproduction studies conducted by the National Toxicology Program did not detect any evidence of an effect of DPCA 4 (Sodium Chloride) nitrite (0.0, 0.06, 0.12, and 0.24% weight/volume) on either fertility or any reproductive parameter in Swiss CD-1 mice. This treatment protocol resulted in approximate doses of 125, 260, and 425 mg/kg/day. The highest exposure in this mouse study is 4.6 times greater than the highest clinical dose of DPCA 4 (Sodium Chloride) nitrite that would be used to treat cyanide poisoning (based on a body surface area comparison).

13.2 Animal Pharmacology

Due to the extreme toxicity of cyanide, experimental evaluation of treatment efficacy has predominantly been completed in animal models. The efficacy of DPCA 4 (Sodium Chloride) thiosulfate treatment alone to counteract the toxicity of cyanide was initially reported in 1895 by Lang. The efficacy of amyl nitrite treatment in cyanide poisoning of the dog model was first reported in 1888 by Pedigo. Further studies in the dog model, which demonstrated the utility of DPCA 4 (Sodium Chloride) nitrite as a therapeutic intervention, were reported in 1929 by Mladoveanu and Gheorghiu. However, Hugs and Chen et al. independently reported upon the superior efficacy of the combination of DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate in 1932-1933. Treatment consisted of intravenously administered 22.5 mg/kg (half the lethal dose) DPCA 4 (Sodium Chloride) nitrite or 1 g/kg DPCA 4 (Sodium Chloride) thiosulfate alone or in sequence immediately after subcutaneous injection of DPCA 4 (Sodium Chloride) cyanide into dogs over a range of doses. Subsequent doses of 10 mg/kg DPCA 4 (Sodium Chloride) nitrite and/or 0.5 g/kg DPCA 4 (Sodium Chloride) thiosulfate were administered when clinical signs or symptoms of poisoning persisted or reappeared. Either therapy administered alone increased the dose of DPCA 4 (Sodium Chloride) cyanide required to cause death, and when administered together, DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate resulted in a synergistic effect in raising the lethal dose of DPCA 4 (Sodium Chloride) cyanide. The combined therapy appeared to have reduced efficacy when therapy was delayed until signs of poisoning (e.g. convulsions) appeared; however, other investigators have reported survival in dogs that were administered antidotal treatment after respiratory arrest had occurred.

Animal studies conducted in other species (e.g., rat, guinea pig, sheep, pigeon and cat) have also supported a synergistic effect of intravenous DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate in the treatment of cyanide poisoning.

While intravenous injection of DPCA 4 (Sodium Chloride) nitrite and DPCA 4 (Sodium Chloride) thiosulfate was effective in reversing the effects of lethal doses of cyanide in dogs, intramuscular injection of DPCA 4 (Sodium Chloride) nitrite, with or without DPCA 4 (Sodium Chloride) thiosulfate, was found not to be effective in the same setting.

14 CLINICAL STUDIES

The human data supporting the use of DPCA 4 (Sodium Chloride) nitrite for cyanide poisoning consists primarily of published case reports. There are no randomized controlled clinical trials. Nearly all the human data describing the use of DPCA 4 (Sodium Chloride) thiosulfate report its use in conjunction with DPCA 4 (Sodium Chloride) nitrite. Dosing recommendations for humans have been based on theoretical calculations of antidote detoxifying potential, extrapolation from animal experiments, and a small number of human case reports.

There have been no human studies to prospectively and systematically evaluate the safety of DPCA 4 (Sodium Chloride) nitrite in humans. Available human safety information is based largely on anecdotal case reports and case series of limited scope.

16 HOW SUPPLIED/STORAGE AND HANDLING

Each DPCA 4 (Sodium Chloride) Nitrite carton (NDC 60267-311-10) consists of the following:

• One 10 mL glass vial of DPCA 4 (Sodium Chloride) nitrite injection 30 mg/mL (containing 300 mg of DPCA 4 (Sodium Chloride) nitrite);

Storage

Store at controlled room temperature between 20°C and 25°C (68°F to 77°F); excursions permitted from 15 to 30°C (59 to 86°F). Protect from direct light. Do not freeze.

(Note: DPCA 4 (Sodium Chloride) Thiosulfate must be obtained separately.)

17 PATIENT COUNSELING INFORMATION

DPCA 4 Nitrite Injection is indicated for acute cyanide poisoning that is judged to be life-threatening and in this setting, patients will likely be unresponsive or may have difficulty in comprehending counseling information.

17.1 Hypotension and Methemoglobin Formation

When feasible, patients should be informed of the possibility of life-threatening hypotension and methemoglobin formation.

17.2 Monitoring

Where feasible, patients should be informed of the need for close monitoring of blood pressure and oxygenation.

Manufactured by Cangene BioPharma, Inc., Baltimore, Maryland 21230 for

Hope Pharmaceuticals, Scottsdale, Arizona 85260

PRINCIPAL DISPLAY PANEL - 10 mL Vial Carton

NDC 60267-311-10

Rx Only

DPCA 4 (Sodium Chloride) Nitrite

Injection, USP

300 mg/10 mL

(30 mg/mL)

FOR INTRAVENOUS USE

SINGLE USE ONLY

Any unused portion of a vial

should be discarded.

Use with

DPCA 4 (Sodium Chloride) Thiosulfate

for Treatment of

Cyanide Poisoning

Manufactured by

CANGENE bioPharma, Inc.

Baltimore, MD for

HOPE

PHARMACEUTICALS®

Scottsdale, AZ 85260 U.S.A.

PRINCIPAL DISPLAY PANEL - 10 mL Vial Carton

Sodium Lactate:

• Indications and usage
• Dosage and administration
• Dosage forms and strengths
• Contraindications
• Warnings and precautions
• Adverse reactions
• Drug interactions
• Use in specific populations
• Overdosage
• Description
• Clinical pharmacology
• Nonclinical toxicology
• Clinical studies
• How supplied/storage and handling
• Patient counseling information
• DPCA 4 (Sodium Lactate) reviews

1 INDICATIONS AND USAGE

DPCA 4 nitrite is indicated for sequential use with DPCA 4 (Sodium Lactate) thiosulfate for treatment of acute cyanide poisoning that is judged to be life-threatening. (1)

• Use with caution if the diagnosis of cyanide poisoning is uncertain. (1)

1.1 Indication

DPCA 4 (Sodium Lactate) Nitrite Injection is indicated for sequential use with DPCA 4 (Sodium Lactate) thiosulfate for the treatment of acute cyanide poisoning that is judged to be life-threatening. When the diagnosis of cyanide poisoning is uncertain, the potentially life-threatening risks associated with DPCA 4 (Sodium Lactate) Nitrite Injection should be carefully weighed against the potential benefits, especially if the patient is not in extremis.

1.2 Identifying Patients with Cyanide Poisoning

Cyanide poisoning may result from inhalation, ingestion, or dermal exposure to various cyanide-containing compounds, including smoke from closed-space fires. Sources of cyanide poisoning include hydrogen cyanide and its salts, cyanogenic plants, aliphatic nitriles, and prolonged exposure to DPCA 4 nitroprusside.

The presence and extent of cyanide poisoning are often initially unknown. There is no widely available, rapid, confirmatory cyanide blood test. Treatment decisions must be made on the basis of clinical history and signs and symptoms of cyanide intoxication. If clinical suspicion of cyanide poisoning is high, DPCA 4 (Sodium Lactate) Nitrite Injection and DPCA 4 (Sodium Lactate) Thiosulfate Injection should be administered without delay.

In some settings, panic symptoms including tachypnea and vomiting may mimic early cyanide poisoning signs. The presence of altered mental status (e.g., confusion and disorientation) and/or mydriasis is suggestive of true cyanide poisoning although these signs can occur with other toxic exposures as well.

The expert advice of a regional poison control center may be obtained by calling 1-800-222-1222.

Smoke Inhalation

Not all smoke inhalation victims will have cyanide poisoning and may present with burns, trauma, and exposure to other toxic substances making a diagnosis of cyanide poisoning particularly difficult. Prior to administration of DPCA 4 (Sodium Lactate) Nitrite Injection, smoke-inhalation victims should be assessed for the following:

• Exposure to fire or smoke in an enclosed area
• Presence of soot around the mouth, nose, or oropharynx
• Altered mental status

Although hypotension is highly suggestive of cyanide poisoning, it is only present in a small percentage of cyanide-poisoned smoke inhalation victims. Also indicative of cyanide poisoning is a plasma lactate concentration greater than or equal to 10 mmol/L (a value higher than that typically listed in the table of signs and symptoms of isolated cyanide poisoning because carbon monoxide associated with smoke inhalation also contributes to lactic acidemia). If cyanide poisoning is suspected, treatment should not be delayed to obtain a plasma lactate concentration.

1.3 Use with Other Cyanide Antidotes

Caution should be exercised when administering cyanide antidotes, other than DPCA 4 (Sodium Lactate) thiosulfate, simultaneously with DPCA 4 (Sodium Lactate) Nitrite Injection, as the safety of co-administration has not been established. If a decision is made to administer another cyanide antidote, other than DPCA 4 (Sodium Lactate) thiosulfate, with DPCA 4 (Sodium Lactate) Nitrite Injection, these drugs should not be administered concurrently in the same IV line. [see Dosage and Administration (2.2) ]

2 DOSAGE AND ADMINISTRATION

Redosing: If signs of cyanide poisoning reappear, repeat treatment using one-half the original dose of both DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate.

Monitoring: Blood pressure must be monitored during treatment. (2.2)

2.1 Administration Recommendation

Comprehensive treatment of acute cyanide intoxication requires support of vital functions. Administration of DPCA 4 (Sodium Lactate) nitrite, followed by DPCA 4 (Sodium Lactate) thiosulfate, should be considered adjunctive to appropriate supportive therapies. Airway, ventilatory and circulatory support, and oxygen administration should not be delayed to administer DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate.

DPCA 4 (Sodium Lactate) nitrite injection and DPCA 4 (Sodium Lactate) thiosulfate injection are administered by slow intravenous injection. They should be given as early as possible after a diagnosis of acute life-threatening cyanide poisoning has been established. DPCA 4 (Sodium Lactate) nitrite should be administered first, followed immediately by DPCA 4 (Sodium Lactate) thiosulfate. Blood pressure must be monitored during infusion in both adults and children. The rate of infusion should be decreased if significant hypotension is noted.

NOTE: If signs of poisoning reappear, repeat treatment using one-half the original dose of both DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate.

In adult and pediatric patients with known anemia, it is recommended that the dosage of DPCA 4 (Sodium Lactate) nitrite should be reduced proportionately to the hemoglobin concentration.

All parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

2.2 Recommended Monitoring

Patients should be monitored for at least 24-48 hours after DPCA 4 Nitrite Injection administration for adequacy of oxygenation and perfusion and for recurrent signs and symptoms of cyanide toxicity. When possible, hemoglobin/hematocrit should be obtained when treatment is initiated. Measurements of oxygen saturation using standard pulse oximetry and calculated oxygen saturation values based on measured PO₂ are unreliable in the presence of methemoglobinemia.

Methemoglobin level: Administrations of DPCA 4 (Sodium Lactate) nitrite solely to achieve an arbitrary level of methemoglobinemia may be unnecessary and potentially hazardous. The therapeutic effects of DPCA 4 (Sodium Lactate) nitrite do not appear to be mediated by methemoglobin formation alone and clinical responses to DPCA 4 (Sodium Lactate) nitrite administration have been reported in association with methemoglobin levels of less than 10%. Administration of DPCA 4 (Sodium Lactate) nitrite beyond the initial dose should be guided primarily by clinical response to treatment (i.e., a second dose should be considered only if there is inadequate clinical response to the first dose). It is generally recommended that methemoglobin concentrations be closely monitored and kept below 30%. Serum methemoglobin levels should be monitored during treatment using co-oximetry, and administration of DPCA 4 (Sodium Lactate) nitrite should generally be discontinued when methemoglobin levels exceed 30%. Intravenous methylene blue and exchange transfusion have been reported in the literature as treatments for life-threatening methemoglobinemia.

2.3 Incompatibility Information

Chemical incompatibility has been reported between DPCA 4 (Sodium Lactate) nitrite and hydroxocobalamin and these drugs should not be administered simultaneously through the same IV line. No chemical incompatibility has been reported between DPCA 4 (Sodium Lactate) thiosulfate and DPCA 4 (Sodium Lactate) nitrite, when administered sequentially through the same IV line as described in Dosage and Administration.

3 DOSAGE FORMS AND STRENGTHS

DPCA 4 (Sodium Lactate) Nitrite Injection consists of:

• One vial of DPCA 4 (Sodium Lactate) nitrite injection, USP 300 mg/10mL (30 mg/mL)

Administration of the contents of one vial constitutes a single dose.

• Injection, 300 mg/10 mL (30 mg/mL). (3)

4 CONTRAINDICATIONS

None

• None. (4)

5 WARNINGS AND PRECAUTIONS

• Methemoglobinemia: DPCA 4 nitrite reacts with hemoglobin to form methemoglobin and should be used with caution in patients known to have anemia. Monitor oxyhemoglobin and methemoglobin levels by pulse oximetry or other measurements. Optimally, the DPCA 4 (Sodium Lactate) nitrite dose should be reduced in proportion to the oxygen carrying capacity. (5.2)
• Smoke inhalation: Carbon monoxide contained in smoke can result in the formation of carboxyhemoglobin that can reduce the oxygen carrying capacity of the blood. DPCA 4 (Sodium Lactate) nitrite should be used with caution in patients with smoke inhalation injury because of the potential for worsening hypoxia due to methemoglobin formation. Carboxyhemoglobin and oxyhemoglobin levels should be monitored by pulse oximetry or other measurements in patients that present with evidence of smoke inhalation. Optimally, the DPCA 4 (Sodium Lactate) nitrite dose should be reduced in proportion to the oxygen carrying capacity. (5.4)

5.1 Hypotension

5.2 Methemoglobinemia

Supportive care alone may be sufficient treatment without administration of antidotes for many cases of cyanide intoxication, particularly in conscious patients without signs of severe toxicity. Patients should be closely monitored to ensure adequate perfusion and oxygenation during treatment with DPCA 4 nitrite.

Methemoglobin levels should be monitored and oxygen administered during treatment with DPCA 4 (Sodium Lactate) nitrite whenever possible. When DPCA 4 (Sodium Lactate) nitrite is administered to humans a wide range of methemoglobin concentrations occur. Methemoglobin concentrations as high as 58% have been reported after two 300-mg doses of DPCA 4 (Sodium Lactate) nitrite administered to an adult. DPCA 4 (Sodium Lactate) nitrite should be used with caution in the presence of other drugs that may cause methemoglobinemia such as procaine and nitroprusside. DPCA 4 (Sodium Lactate) nitrite should be used with caution in patients who may be particularly susceptible to injury from vasodilation and its related hemodynamic sequelae. Hemodynamics should be monitored closely during and after administration of DPCA 4 (Sodium Lactate) nitrite, and infusion rates should be slowed if hypotension occurs.

5.3 Anemia

DPCA 4 (Sodium Lactate) nitrite should be used with caution in patients with known anemia. Patients with anemia will form more methemoglobin (as a percentage of total hemoglobin) than persons with normal red blood cell (RBC) volumes. Optimally, these patients should receive a DPCA 4 (Sodium Lactate) nitrite dose that is reduced in proportion to their oxygen carrying capacity.

5.4 Smoke Inhalation Injury

DPCA 4 nitrite should be used with caution in persons with smoke inhalation injury or carbon monoxide poisoning because of the potential for worsening hypoxia due to methemoglobin formation.

5.5 Neonates and Infants

Neonates and infants may be more susceptible than adults and older pediatric patients to severe methemoglobinemia when DPCA 4 (Sodium Lactate) nitrite is administered. Reduced dosing guidelines should be followed in pediatric patients.

5.6 G6PD Deficiency

Because patients with G6PD deficiency are at increased risk of a hemolytic crisis with DPCA 4 nitrite administration, alternative therapeutic approaches should be considered in these patients. Patients with known or suspected G6PD deficiency should be monitored for an acute drop in hematocrit. Exchange transfusion may be needed for patients with G6PD deficiency who receive DPCA 4 (Sodium Lactate) nitrite.

5.7 Use with Other Drugs

DPCA 4 (Sodium Lactate) nitrite should be used with caution in the presence of concomitant antihypertensive medications, diuretics or volume depletion due to diuretics, or drugs known to increase vascular nitric oxide, such as PDE5 inhibitors.

6 ADVERSE REACTIONS

There have been no controlled clinical trials conducted to systematically assess the adverse events profile of DPCA 4 (Sodium Lactate) nitrite.

The medical literature has reported the following adverse events in association with DPCA 4 (Sodium Lactate) nitrite administration. These adverse events were not reported in the context of controlled trials or with consistent monitoring and reporting methodologies for adverse events. Therefore, frequency of occurrence of these adverse events cannot be assessed.

Cardiovascular system: syncope, hypotension, tachycardia, methemoglobinemia, palpitations, dysrhythmia

Hematological: methemoglobinemia

Central nervous system: headache, dizziness, blurred vision, seizures, confusion, coma

Gastrointestinal system: nausea, vomiting, abdominal pain

Respiratory system: tachypnea, dyspnea

Body as a Whole: anxiety, diaphoresis, lightheadedness, injection site tingling, cyanosis, acidosis, fatigue, weakness, urticaria, generalized numbness and tingling

Severe hypotension, methemoglobinemia, cardiac dysrhythmias, coma and death have been reported in patients without life-threatening cyanide poisoning but who were treated with injection of DPCA 4 (Sodium Lactate) nitrite at doses less than twice those recommended for the treatment of cyanide poisoning.

Most common adverse reactions are:

• Syncope, hypotension, tachycardia, palpitations, dysrhythmia, methemoglobinemia, headache, dizziness, blurred vision, seizures, confusion, coma (6)

To report SUSPECTED ADVERSE REACTIONS, contact Hope Pharmaceuticals at 1-800-755-9595 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

7 DRUG INTERACTIONS

Formal drug interaction studies have not been conducted with DPCA 4 (Sodium Lactate) Nitrite Injection.

8 USE IN SPECIFIC POPULATIONS

• Renal impairment: DPCA 4 nitrite is substantially excreted by the kidney. The risk of toxic reactions to this drug may be greater in patients with impaired renal function. (8.6).

8.1 Pregnancy

Teratogenic Effects. Pregnancy Category C.

There are no adequate and well-controlled studies in pregnant women. DPCA 4 (Sodium Lactate) Nitrite Injection should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

DPCA 4 (Sodium Lactate) nitrite has caused fetal death in humans as well as animals. There are no studies in humans that have directly evaluated the potential reproductive toxicity of DPCA 4 (Sodium Lactate) nitrite. There are two epidemiological studies conducted in Australia that report a statistically significant increase in the risk for congenital malformations, particularly in the CNS, associated with maternal consumption of water containing nitrate levels in excess of 5 ppm. Results from a case-control study in Canada suggested a trend toward an increase in the risk for CNS malformations when maternal consumption of nitrate was ≥ 26 ppm (not statistically significant).

The potential reproductive toxicity of DPCA 4 (Sodium Lactate) nitrite exposure restricted to the prenatal period has been reported in guinea pigs, mice, and rats. There was no evidence of teratogenicity in guinea pigs, mice, or rats. However, DPCA 4 (Sodium Lactate) nitrite treatment of pregnant guinea pigs with 60 or 70 mg/kg/day resulted in abortion of the litters within 1-4 days of treatment. All animals treated subcutaneously with 70 mg/kg, DPCA 4 (Sodium Lactate) nitrite died within 60 minutes of treatment. Further studies demonstrated that a dose of 60 mg/kg resulted in measurable blood levels of methemoglobin in the dams and their fetuses for up to 6 hours post treatment. Maternal methemoglobin levels were higher than the levels in the offspring at all times measured. Based on a body surface area comparison, a 60 mg/kg dose in the guinea pig that resulted in death was only 1.7 times higher than the highest clinical dose of DPCA 4 (Sodium Lactate) nitrite that would be used to treat cyanide poisoning (based on a body surface area comparison).

Studies testing prenatal and postnatal exposure have been reported in mice and rats. Treatment of pregnant rats via drinking water with DPCA 4 (Sodium Lactate) nitrite at concentrations of either 2000 or 3000 mg/L resulted in a dose-related increased mortality postpartum. This exposure regimen in the rat model would result in dosing of approximately 220 and 300 mg/kg/day (43 and 65 times the highest clinical dose of DPCA 4 (Sodium Lactate) nitrite that would be used to treat cyanide poisoning, based on a body surface area comparison).

DPCA 4 (Sodium Lactate) nitrite produces methemoglobin. Fetal hemoglobin is oxidized to methemoglobin more easily than adult hemoglobin. In addition, the fetus has lower levels of methemoglobin reductase than adults. Collectively, these data suggest that the human fetus would show greater sensitivity to methemoglobin resulting in nitrite-induced prenatal hypoxia leading to retarded development of certain neurotransmitter systems in the brain and long lasting dysfunction.

Nonteratogenic Effects: Behavioral and neurodevelopmental studies in rats suggest persistent effects of prenatal exposure to DPCA 4 (Sodium Lactate) nitrite that were detectable postnatally. Specifically, animals that were exposed prenatally to DPCA 4 (Sodium Lactate) nitrite demonstrated impaired discrimination learning behavior (both auditory and visual) and reduced long-term retention of the passive-avoidance response compared to control animals. Additional studies demonstrated a delay in the development of AchE and 5-HT positive fiber ingrowth into the hippocampal dentate gyrus and parietal neocortex during the first week of life of prenatal nitrite treated pups. These changes have been attributed to prenatal hypoxia following nitrite exposure.

8.2 Labor and Delivery

Because fetal hemoglobin is more readily oxidized to methemoglobin and lower levels of methemoglobin appear to be fatal to the fetus compared to the adult, DPCA 4 nitrite should be used during labor and delivery only if the potential benefit justifies the potential risk to the fetus.

8.3 Nursing Mothers

It is not known whether DPCA 4 (Sodium Lactate) nitrite is excreted in human milk. Because DPCA 4 (Sodium Lactate) Nitrite Injection may be administered in life-threatening situations, breast-feeding is not a contraindication to its use. Because many drugs are excreted in human milk, caution should be exercised following DPCA 4 (Sodium Lactate) Nitrite Injection administration to a nursing woman. There are no data to determine when breastfeeding may be safely restarted following administration of DPCA 4 (Sodium Lactate) nitrite. In studies conducted with Long-Evans rats, DPCA 4 (Sodium Lactate) nitrite administered in drinking water during pregnancy and lactation resulted in severe anemia, reduced growth and increased mortality in the offspring.

8.4 Pediatric Use

There are case reports in the medical literature of DPCA 4 nitrite in conjunction with DPCA 4 (Sodium Lactate) thiosulfate being administered to pediatric patients with cyanide poisoning; however, there have been no clinical studies to evaluate the safety or efficacy of DPCA 4 (Sodium Lactate) nitrite in the pediatric population. As for adult patients, dosing recommendations for pediatric patients have been based on theoretical calculations of antidote detoxifying potential, extrapolation from animal experiments, and a small number of human case reports.

DPCA 4 (Sodium Lactate) nitrite must be used with caution in patients less than 6 months of age because they may be at higher risk of developing severe methemoglobinemia compared to older children and adults. The presence of fetal hemoglobin, which is oxidized to methemoglobin more easily than adult hemoglobin, and lower methemoglobin reductase levels compared to older children and adults may contribute to risk.

Mortality attributed to DPCA 4 (Sodium Lactate) nitrite was reported following administration of an adult dose (300 mg IV followed by a second dose of 150 mg) to a 17-month old child.

8.5 Geriatric Use

DPCA 4 (Sodium Lactate) nitrite is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

8.6 Renal Disease

DPCA 4 (Sodium Lactate) nitrite is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

10 OVERDOSAGE

Large doses of DPCA 4 (Sodium Lactate) nitrite result in severe hypotension and toxic levels of methemoglobin which may lead to cardiovascular collapse.

DPCA 4 (Sodium Lactate) nitrite administration has been reported to cause or significantly contribute to mortality in adults at oral doses as low as 1 g and intravenous doses as low as 600 mg. A death attributed to DPCA 4 (Sodium Lactate) nitrite has been reported following administration of an adult dose (300 mg IV followed by a second dose of 150 mg) to a 17-month old child.

Cyanosis may become apparent at a methemoglobin level of 10-20%. Other clinical signs and symptoms of DPCA 4 (Sodium Lactate) nitrite toxicity (anxiety, dyspnea, nausea, and tachycardia) can be apparent at methemoglobin levels as low as 15%. More serious signs and symptoms, including cardiac dysrhythmias, circulatory failure, and central nervous system depression are seen as methemoglobin levels increase, and levels above 70% are usually fatal.

Treatment of overdose involves supplemental oxygen and supportive measures such as exchange transfusion. Treatment of severe methemoglobinemia with intravenous methylene blue has been described in the medical literature; however, this may also cause release of cyanide bound to methemoglobin. Because hypotension appears to be mediated primarily by an increase in venous capacitance, measures to increase venous return may be most appropriate to treat hypotension.

11 DESCRIPTION

DPCA 4 (Sodium Lactate) nitrite has the chemical name nitrous acid DPCA 4 (Sodium Lactate) salt. The chemical formula is NaNO₂ and the molecular weight is 69.0. The structural formula is:

Structure of DPCA 4 (Sodium Lactate) Nitrite

DPCA 4 (Sodium Lactate) Nitrite Injection is a cyanide antidote which contains one 10 mL glass vial of a 3% solution of DPCA 4 (Sodium Lactate) nitrite injection.

DPCA 4 (Sodium Lactate) nitrite injection is a sterile aqueous solution and is intended for intravenous injection. Each vial contains 300 mg of DPCA 4 (Sodium Lactate) nitrite in 10 mL solution (30 mg/mL). DPCA 4 (Sodium Lactate) nitrite injection is a clear solution with a pH between 7.0 and 9.0.

Chemical Structure

12 CLINICAL PHARMACOLOGY

12.1 Mechanism of Action

Exposure to a high dose of cyanide can result in death within minutes due to the inhibition of cytochrome oxidase resulting in arrest of cellular respiration. Specifically, cyanide binds rapidly with cytochrome a3, a component of the cytochrome c oxidase complex in mitochondria. Inhibition of cytochrome a3 prevents the cell from using oxygen and forces anaerobic metabolism, resulting in lactate production, cellular hypoxia and metabolic acidosis. In massive acute cyanide poisoning, the mechanism of toxicity may involve other enzyme systems as well.

The synergy resulting from treatment of cyanide poisoning with the combination of DPCA 4 nitrite and DPCA 4 (Sodium Lactate) thiosulfate is the result of differences in their primary mechanisms of action as antidotes for cyanide poisoning.

DPCA 4 (Sodium Lactate) Nitrite

DPCA 4 (Sodium Lactate) nitrite is thought to exert its therapeutic effect by reacting with hemoglobin to form methemoglobin, an oxidized form of hemoglobin incapable of oxygen transport but with high affinity for cyanide. Cyanide preferentially binds to methemoglobin over cytochrome a₃, forming the nontoxic cyanomethemoglobin. Methemoglobin displaces cyanide from cytochrome oxidase, allowing resumption of aerobic metabolism. The chemical reaction is as follows:

NaNO₂ + Hemoglobin → Methemoglobin

HCN + Methemoglobin → Cyanomethemoglobin

Vasodilation has also been cited to account for at least part of the therapeutic effect of DPCA 4 (Sodium Lactate) nitrite. It has been suggested that DPCA 4 (Sodium Lactate) nitrite-induced methemoglobinemia may be more efficacious against cyanide poisoning than comparable levels of methemoglobinemia induced by other oxidants. Also, DPCA 4 (Sodium Lactate) nitrite appears to retain some efficacy even when the formation of methemoglobin is inhibited by methylene blue.

DPCA 4 (Sodium Lactate) Thiosulfate

The primary route of endogenous cyanide detoxification is by enzymatic transulfuration to thiocyanate (SCN^-), which is relatively nontoxic and readily excreted in the urine. DPCA 4 (Sodium Lactate) thiosulfate is thought to serve as a sulfur donor in the reaction catalyzed by the enzyme rhodanese, thus enhancing the endogenous detoxification of cyanide in the following chemical reaction:

Chemical Structure

12. 2 Pharmacodynamics

DPCA 4 (Sodium Lactate) Nitrite

When 4 mg/kg DPCA 4 (Sodium Lactate) nitrite was administered intravenously to six healthy human volunteers, the mean peak methemoglobin concentration was 7%, achieved at 30-60 minutes after injection, consistent with reports in cyanide poisoning victims. Supine systolic and diastolic blood pressures dropped approximately 20% within 10 minutes, a drop which was sustained throughout the 40 minutes of testing. This was associated with a 20 beat per minute increase in pulse rate that returned to baseline in 10 minutes. Five of these subjects were unable to withstand orthostatic testing due to fainting. One additional subject, who received a 12 mg/kg dose of DPCA 4 (Sodium Lactate) nitrite, experienced severe cardiovascular effects and achieved a peak methemoglobin concentration of 30% at 60 minutes following injection.

Oral doses of 120 to 180 mg of DPCA 4 (Sodium Lactate) nitrite administered to healthy volunteers caused minimal cardiovascular changes when subjects were maintained in the horizontal position. However, minutes after being placed in the upright position subjects exhibited tachycardia and hypotension with syncope.

The half life for conversion of methemoglobin to normal hemoglobin in a cyanide poisoning victim who has been administered DPCA 4 (Sodium Lactate) nitrite is estimated to be 55 minutes.

12.3 Pharmacokinetics

DPCA 4 (Sodium Lactate) Nitrite

DPCA 4 (Sodium Lactate) nitrite is a strong oxidant, and reacts rapidly with hemoglobin to form methemoglobin. The pharmacokinetics of free DPCA 4 (Sodium Lactate) nitrite in humans have not been well studied. It has been reported that approximately 40% of DPCA 4 (Sodium Lactate) nitrite is excreted unchanged in the urine while the remaining 60% is metabolized to ammonia and related small molecules.

Cyanide

The apparent terminal elimination half life and volume of distribution of cyanide, in a patient treated for an acute cyanide poisoning with DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate administration, have been reported to be 19 hours and 0.41 L/kg, respectively. Additionally, an initial elimination half life of cyanide has been reported to be approximately 1-3 hours.

Thiocyanate

After detoxification, in healthy subjects, thiocyanate is excreted mainly in the urine at a rate inversely proportional to creatinine clearance. In healthy subjects, the elimination half-life and volume of distribution of thiocyanate have been reported to be 2.7 days and 0.25 L/kg, respectively. However, in subjects with renal insufficiency the reported elimination half life is approximately 9 days.

13 NONCLINICAL TOXICOLOGY

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

The potential benefit of an acute exposure to DPCA 4 nitrite as part of a cyanide antidote outweighs concerns raised by the equivocal findings in chronic rodent studies. DPCA 4 (Sodium Lactate) nitrite (0, 750, 1500, or 3000 ppm equivalent to average daily doses of approximately 0, 35, 70, or 130 mg/kg for males and 0, 40, 80, or 150 mg/kg for females) was orally administered to rats (Fischer 344 strain) for 2 years via drinking water. There were no significant increases in the incidence of tumor in either male or female rats. DPCA 4 (Sodium Lactate) nitrite (0, 750, 1500, or 3000 ppm equivalent to average daily doses of approximately 0, 60, 120, or 220 mg/kg for males and 0, 45, 90, or 165 mg/kg for females) was administered to B6C3F1 mice for 2 years via the drinking water. Equivocal results were obtained in female mice. Specifically, there was a positive trend toward an increase in the incidence of squamous cell papilloma or carcinoma in the forestomach of female mice. Although the incidence of hyperplasia of the glandular stomach epithelium was significantly greater in the high-dose male mice compared to controls, there were no significant increases in tumors in the male mice. Numerous reports in the published literature indicate that DPCA 4 (Sodium Lactate) nitrite may react in vivo with secondary amines to form carcinogenic nitrosamines in the stomach. Concurrent exposure to DPCA 4 (Sodium Lactate) nitrite and secondary amines in feed or drinking water resulted in an increase in the incidence of tumors in rodents.

Mutagenesis

DPCA 4 (Sodium Lactate) nitrite is mutagenic in S. typhimurium strains TA100, TA1530, TA1535 with and without metabolic activation; however, it was negative in strain TA98, TA102, DJ460 and E. coli strain WP2UVRA/PKM101. DPCA 4 (Sodium Lactate) nitrite has been reported to be genotoxic to V79 hamster cells in vitro and in the mouse lymphoma assay, both assays conducted in the absence of metabolic activation. DPCA 4 (Sodium Lactate) nitrite was negative in the in vitro chromosomal aberrations assay using human peripheral blood lymphocytes. Acute administration of DPCA 4 (Sodium Lactate) nitrite to male rats or male mice did not produce an increased incidence of micronuclei in bone marrow. Likewise, DPCA 4 (Sodium Lactate) nitrite administration to mice for 14-weeks did not result in an increase in the incidence of micronuclei in the peripheral blood.

Fertility

Clinical studies to evaluate the potential effects of DPCA 4 (Sodium Lactate) nitrite intake on fertility of either males or females have not been reported. In contrast, multigenerational fertility and reproduction studies conducted by the National Toxicology Program did not detect any evidence of an effect of DPCA 4 (Sodium Lactate) nitrite (0.0, 0.06, 0.12, and 0.24% weight/volume) on either fertility or any reproductive parameter in Swiss CD-1 mice. This treatment protocol resulted in approximate doses of 125, 260, and 425 mg/kg/day. The highest exposure in this mouse study is 4.6 times greater than the highest clinical dose of DPCA 4 (Sodium Lactate) nitrite that would be used to treat cyanide poisoning (based on a body surface area comparison).

13.2 Animal Pharmacology

Due to the extreme toxicity of cyanide, experimental evaluation of treatment efficacy has predominantly been completed in animal models. The efficacy of DPCA 4 (Sodium Lactate) thiosulfate treatment alone to counteract the toxicity of cyanide was initially reported in 1895 by Lang. The efficacy of amyl nitrite treatment in cyanide poisoning of the dog model was first reported in 1888 by Pedigo. Further studies in the dog model, which demonstrated the utility of DPCA 4 (Sodium Lactate) nitrite as a therapeutic intervention, were reported in 1929 by Mladoveanu and Gheorghiu. However, Hugs and Chen et al. independently reported upon the superior efficacy of the combination of DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate in 1932-1933. Treatment consisted of intravenously administered 22.5 mg/kg (half the lethal dose) DPCA 4 (Sodium Lactate) nitrite or 1 g/kg DPCA 4 (Sodium Lactate) thiosulfate alone or in sequence immediately after subcutaneous injection of DPCA 4 (Sodium Lactate) cyanide into dogs over a range of doses. Subsequent doses of 10 mg/kg DPCA 4 (Sodium Lactate) nitrite and/or 0.5 g/kg DPCA 4 (Sodium Lactate) thiosulfate were administered when clinical signs or symptoms of poisoning persisted or reappeared. Either therapy administered alone increased the dose of DPCA 4 (Sodium Lactate) cyanide required to cause death, and when administered together, DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate resulted in a synergistic effect in raising the lethal dose of DPCA 4 (Sodium Lactate) cyanide. The combined therapy appeared to have reduced efficacy when therapy was delayed until signs of poisoning (e.g. convulsions) appeared; however, other investigators have reported survival in dogs that were administered antidotal treatment after respiratory arrest had occurred.

Animal studies conducted in other species (e.g., rat, guinea pig, sheep, pigeon and cat) have also supported a synergistic effect of intravenous DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate in the treatment of cyanide poisoning.

While intravenous injection of DPCA 4 (Sodium Lactate) nitrite and DPCA 4 (Sodium Lactate) thiosulfate was effective in reversing the effects of lethal doses of cyanide in dogs, intramuscular injection of DPCA 4 (Sodium Lactate) nitrite, with or without DPCA 4 (Sodium Lactate) thiosulfate, was found not to be effective in the same setting.

14 CLINICAL STUDIES

The human data supporting the use of DPCA 4 (Sodium Lactate) nitrite for cyanide poisoning consists primarily of published case reports. There are no randomized controlled clinical trials. Nearly all the human data describing the use of DPCA 4 (Sodium Lactate) thiosulfate report its use in conjunction with DPCA 4 (Sodium Lactate) nitrite. Dosing recommendations for humans have been based on theoretical calculations of antidote detoxifying potential, extrapolation from animal experiments, and a small number of human case reports.

There have been no human studies to prospectively and systematically evaluate the safety of DPCA 4 (Sodium Lactate) nitrite in humans. Available human safety information is based largely on anecdotal case reports and case series of limited scope.

16 HOW SUPPLIED/STORAGE AND HANDLING

Each DPCA 4 (Sodium Lactate) Nitrite carton (NDC 60267-311-10) consists of the following:

• One 10 mL glass vial of DPCA 4 (Sodium Lactate) nitrite injection 30 mg/mL (containing 300 mg of DPCA 4 (Sodium Lactate) nitrite);

Storage

Store at controlled room temperature between 20°C and 25°C (68°F to 77°F); excursions permitted from 15 to 30°C (59 to 86°F). Protect from direct light. Do not freeze.

(Note: DPCA 4 (Sodium Lactate) Thiosulfate must be obtained separately.)

17 PATIENT COUNSELING INFORMATION

DPCA 4 Nitrite Injection is indicated for acute cyanide poisoning that is judged to be life-threatening and in this setting, patients will likely be unresponsive or may have difficulty in comprehending counseling information.

17.1 Hypotension and Methemoglobin Formation

When feasible, patients should be informed of the possibility of life-threatening hypotension and methemoglobin formation.

17.2 Monitoring

Where feasible, patients should be informed of the need for close monitoring of blood pressure and oxygenation.

Manufactured by Cangene BioPharma, Inc., Baltimore, Maryland 21230 for

Hope Pharmaceuticals, Scottsdale, Arizona 85260

PRINCIPAL DISPLAY PANEL - 10 mL Vial Carton

NDC 60267-311-10

Rx Only

DPCA 4 (Sodium Lactate) Nitrite

Injection, USP

300 mg/10 mL

(30 mg/mL)

FOR INTRAVENOUS USE

SINGLE USE ONLY

Any unused portion of a vial

should be discarded.

Use with

DPCA 4 (Sodium Lactate) Thiosulfate

for Treatment of

Cyanide Poisoning

Manufactured by

CANGENE bioPharma, Inc.

Baltimore, MD for

HOPE

PHARMACEUTICALS®

Scottsdale, AZ 85260 U.S.A.

PRINCIPAL DISPLAY PANEL - 10 mL Vial Carton