Cyanocobalamin is a synthetic form of vitamin B12 with equivalent vitamin B12 activity. The chemical name is 5,6-dimethyl-benzimidazolyl cyanocobamide. The cobalt content is 4.35%. The molecular formula is C63H88CoN14O14P, which corresponds to a molecular weight of 1355.38 and the following structural formula:

Cyanocobalamin occurs as dark red crystals or orthorhombic needles or crystalline red powder. It is very hygroscopic in the anhydrous form, and sparingly to moderately soluble in water (1:80). Its pharmacologic activity is destroyed by heavy metals (iron) and strong oxidizing or reducing agents (vitamin C), but not by autoclaving for short periods of time (15-20 minutes) at 121°C. The vitamin B12 coenzymes are very unstable in light.

Nascobal® Nasal Spray is a solution of Cyanocobalamin, USP (vitamin B12) for administration as a spray to the nasal mucosa. Each bottle of Nascobal Nasal Spray contains 1.3mL of a 500 mcg/0.1mL solution of cyanocobalamin with sodium citrate, citric acid, and glycerin and benzalkonium chloride in purified water. The spray solution has a pH between 4.5 and 5.5. The spray pump unit must be fully primed (see Dosage and Administration) prior to initial use. After initial priming, each spray delivers an average of 500 mcg of cyanocobalamin and the 1.3mL of spray solution contained in the bottle will deliver 4 doses of Nascobal Nasal Spray. The unit must be re-primed before each dose. (see Dosage and Administration).

Nascobal Nasal Spray is indicated for the maintenance of normal hematologic status in pernicious anemia patients who are in remission following intramuscular vitamin B12 therapy and who have no nervous system involvement.

Nascobal Nasal Spray is also indicated as a supplement for other vitamin B12 deficiencies, including:

   I. Dietary deficiency of vitamin B12 occurring in strict vegetarians (Isolated vitamin B12 deficiency is very rare).

   II. Malabsorption of vitamin B12 resulting from structural or functional damage to the stomach, where intrinsic factor is secreted, or to the ileum, where intrinsic factor facilitates vitamin B12 absorption. These conditions include HIV infection, AIDS, Crohn's disease, tropical sprue, and nontropical sprue (idiopathic steatorrhea, gluten-induced enteropathy). Folate deficiency in these patients is usually more severe than vitamin B12 deficiency.

   III. Inadequate secretion of intrinsic factor, resulting from lesions that destroy the gastric mucosa (ingestion of corrosives, extensive neoplasia), and a number of conditions associated with a variable degree of gastric atrophy (such as multiple sclerosis, HIV infection, AIDS, certain endocrine disorders, iron deficiency, and subtotal gastrectomy). Total gastrectomy always produces vitamin B12 deficiency. Structural lesions leading to vitamin B12 deficiency include regional ileitis, ileal resections, malignancies, etc.

   IV. Competition for vitamin B12 by intestinal parasites or bacteria. The fish tapeworm (Diphyllobothrium latum) absorbs huge quantities of vitamin B12 and infested patients often have associated gastric atrophy. The blind loop syndrome may produce deficiency of vitamin B12 or folate.

   V. Inadequate utilization of vitamin B12. This may occur if antimetabolites for the vitamin are employed in the treatment of neoplasia.

Requirements of vitamin B12 in excess of normal (due to pregnancy, thyrotoxicosis, hemolytic anemia, hemorrhage, malignancy, hepatic and renal disease) can usually be met with intranasal or oral supplementation.

Nascobal Nasal Spray is not suitable for vitamin B12 absorption test (Schilling Test).

Sensitivity to cobalt and/or vitamin B12 or any component of the medication is a contraindication.

Patients with early Leber's disease (hereditary optic nerve atrophy) who were treated with vitamin B12 suffered severe and swift optic atrophy.

Hypokalemia and sudden death may occur in severe megaloblastic anemia which is treated intensely with vitamin B12. Folic acid is not a substitute for vitamin B12 although it may improve vitamin B12-deficient megaloblastic anemia. Exclusive use of folic acid in treating vitamin B12-deficient megaloblastic anemia could result in progressive and irreversible neurologic damage.

Anaphylactic shock and death have been reported after parenteral vitamin B12 administration. No such reactions have been reported in clinical trials with Nascobal Nasal Spray or Nascobal Nasal Gel.

Blunted or impeded therapeutic response to vitamin B12 may be due to such conditions as infection, uremia, drugs having bone marrow suppressant properties such as chloramphenicol, and concurrent iron or folic acid deficiency.

The incidence of adverse experiences described in the Table below are based on data from a short-term clinical trial in vitamin B12 deficient patients in hematologic remission receiving Nascobal (Cyanocobalamin, USP) Gel for Intranasal Administration (N=24) and intramuscular vitamin B12 (N=25). In the pharmacokinetic study comparing Nascobal Nasal Spray and Nascobal Nasal Gel, the incidence of adverse events was similar.

The intensity of the reported adverse experiences following the administration of Nascobal (Cyanocobalamin, USP) Gel for Intranasal Administration and intramuscular vitamin B12 were generally mild. One patient reported severe headache following intramuscular dosing. Similarly, a few adverse experiences of moderate intensity were reported following intramuscular dosing (two headaches and rhinitis; one dyspepsia, arthritis, and dizziness), and dosing with Nascobal (Cyanocobalamin, USP) Gel for Intranasal Administration (one headache, infection, and paresthesia).

The majority of the reported adverse experiences following dosing with Nascobal (Cyanocobalamin, USP) Gel for Intranasal Administration and intramuscular vitamin B12 were judged to be intercurrent events. For the other reported adverse experiences, the relationship to study drug was judged as "possible" or "remote". Of the adverse experiences judged to be of "possible" relationship to the study drug, anxiety, incoordination, and nervousness were reported following intramuscular vitamin B12 and headache, nausea, and rhinitis were reported following dosing with Nascobal (Cyanocobalamin, USP) Gel for Intranasal Administration.

The following adverse reactions have been reported with parenteral vitamin B12:

Cardiovascular: Pulmonary edema and congestive heart failure early in treatment; peripheral vascular thrombosis.

Hematological: Polycythemia vera.

Gastrointestinal: Mild transient diarrhea.

Dermatological: Itching; transitory exanthema.

Miscellaneous: Feeling of swelling of the entire body.

No overdosage has been reported with Nascobal Nasal Spray, Nascobal (Cyanocobalamin, USP) Gel for Intranasal Administration or parenteral vitamin B12.

The recommended initial dose of Nascobal Nasal Spray is one spray (500 mcg) administered in ONE nostril once weekly. Nascobal Nasal Spray should be administered at least one hour before or one hour after ingestion of hot foods or liquids. Periodic monitoring of serum B12 levels should be obtained to establish adequacy of therapy.

Priming (Activation) of Pump

Before the first dose and administration, the pump must be primed. Remove the clear plastic safety clip from the pump. To prime the pump, place nozzle between the first and second finger with the thumb on the bottom of the bottle. Pump the unit firmly and quickly until the first appearance of spray. Then prime the pump an additional 2 times. Now the nasal spray is ready for use. The unit must be re-primed before each dose. Prime the pump once immediately before each administration of dose 2 through 4.

See LABORATORY TESTS for monitoring B12 levels and adjustment of dosage.

Nascobal Nasal Spray is available as a spray in 3 mL glass bottles containing 1.3 mL of solution. It is available in a dosage strength of 500 mcg per actuation (0.1 mL/actuation). A screw-on actuator is provided. This actuator, following priming, will deliver 0.1 mL of the spray. Nascobal Nasal Spray is provided in a carton containing a nasal spray actuator with dust cover, a bottle of nasal spray solution, and a package insert. One bottle will deliver 4 doses (NDC 49884-270-86).

PHARMACIST ASSEMBLY INSTRUCTIONS FOR NASCOBAL NASAL SPRAY

The pharmacist should assemble the Nascobal Nasal Spray unit prior to dispensing to the patient, according to the following instructions:

1.

Open the carton and remove the spray actuator and spray solution bottle.

2.

Assemble Nascobal Nasal Spray by first unscrewing the white cap from the spray solution bottle and screwing the actuator unit tightly onto the bottle. Make sure the clear dust cover is on the pump unit.

3.

Return the Nascobal Nasal Spray bottle to the carton for dispensing to the patient.

Patients with pernicious anemia should be instructed that they will require weekly intranasal administration of Nascobal Nasal Spray for the remainder of their lives. Failure to do so will result in return of the anemia and in development of incapacitating and irreversible damage to the nerves of the spinal cord. Also, patients should be warned about the danger of taking folic acid in place of vitamin B12, because the former may prevent anemia but allow progression of subacute combined degeneration of the spinal cord.

(Hot foods may cause nasal secretions and a resulting loss of medication; therefore, patients should be told to administer Nascobal Nasal Spray at least one hour before or one hour after ingestion of hot foods or liquids.)

A vegetarian diet which contains no animal products (including milk products or eggs) does not supply any vitamin B12. Therefore, patients following such a diet should be advised to take Nascobal Nasal Spray weekly. The need for vitamin B12 is increased by pregnancy and lactation. Deficiency has been recognized in infants of vegetarian mothers who were breast fed, even though the mothers had no symptoms of deficiency at the time.

Because the nasal dosage forms of Vitamin B12 have a lower absorption than intramuscular dosage, nasal dosage forms are administered weekly, rather than the monthly intramuscular dosage. As shown in the Figure above, at the end of a month, weekly nasal administration results in significantly higher serum Vitamin B12 levels than after intramuscular administration. The patient should also understand the importance of returning for follow-up blood tests every 3 to 6 months to confirm adequacy of the therapy.

Careful instructions on the actuator assembly, removal of safety clip, priming of the actuator and nasal administration of Nascobal Nasal Spray should be given to the patient. Although instructions for patients are supplied with individual bottles, procedures for use should be demonstrated to each patient.

Protect from light. Keep covered in carton until ready to use. Store upright at controlled room temperature 15°C to 30°C (59°F to 86°F). Protect from freezing.

To report suspected adverse reactions, contact Par Pharmaceutical Companies, Inc. at 1-800-828-9393

Distributed by:

Par Pharmaceutical Companies, Inc

Spring Valley, NY 10977

OS270-01-03

Rev. 07/2011

FOR NASAL USE ONLY

KEEP OUT OF REACH OF CHILDREN

Each 0.1 mL contains 500mcg Cyancobalamin USP and the following inactive ingredients: Citric Acid USP, Sodium Citrate USP, Glycerin USP, Benzalkonium Chloride NF and Purified Water USP.

One bottle will deliver four doses.

Read instructions carefully before using.

See package insert for complete prescribing information.

Store upright at controlled room temperature 15°-30° C (59°-86° F).