Hemin

PANHEMATIN is a hemin for injection indicated for the amelioration of recurrent attacks of acute intermittent porphyria temporally related to the menstrual cycle in susceptible women, after initial carbohydrate therapy is known or suspected to be inadequate. Limitations of Use

• Before administering PANHEMATIN, consider an appropriate period of carbohydrate loading (i.e., 400 g glucose/day for 1 to 2 days) [ See Dosage and Administration ( 2.1 ) ].
• Attacks of porphyria may progress to a point where irreversible neuronal damage has occurred. PANHEMATIN therapy is intended to prevent an attack from reaching the critical stage of neuronal degeneration. PANHEMATIN is not effective in repairing neuronal damage. PANHEMATIN is a hemin for injection indicated for amelioration of recurrent attacks of acute intermittent porphyria temporally related to the menstrual cycle in susceptible women, after initial carbohydrate therapy is known or suspected to be inadequate. ( 1 ) Limitations of Use
• Before administering PANHEMATIN, consider an appropriate period of carbohydrate loading (i.e., 400 g glucose/day for 1 to 2 days). ( 1 )
• PANHEMATIN is not effective in repairing neuronal damage due to progression of porphyria attacks. ( 1 )

PANHEMATIN is available as a sterile, lyophilized black powder in single dose dispensing vials. Each vial contains the equivalent of 350 mg hemin, 240 mg sodium carbonate and 335 mg of sorbitol. When mixed as directed with Sterile Water for Injection, USP, each 48 mL provides the equivalent of approximately 336 mg hematin (7 mg/mL). PANHEMATIN is available as a sterile, lyophilized powder for reconstitution for injection. Each vial contains the equivalent of 350 mg hemin, 240 mg sodium carbonate and 335 mg of sorbitol. When mixed as directed with Sterile Water for Injection, USP, each 48 mL provides the equivalent of approximately 336 mg hematin (7 mg/mL). ( 3 )

PANHEMATIN is contraindicated in patients with known hypersensitivity to this drug. Do not use in patients with known hypersensitivity to PANHEMATIN. ( 4 )

• Phlebitis is possible. Utilize a large arm vein or a central venous catheter for administration to minimize the risk of phlebitis. ( 5.1 )
• Elevated iron and serum ferritin may occur. Monitor iron and serum ferritin in patients receiving multiple administrations of PANHEMATIN. ( 5.2 )
• PANHEMATIN has transient and mild anticoagulant effect. Avoid concurrent anticoagulant therapy. ( 5.3 )
• Reversible renal shutdown has been observed with an excessive hematin dose (12.2 mg/kg in a single infusion). Strictly follow recommended dosage guidelines. ( 5.4 )
• PANHEMATIN may carry a risk of transmitting infectious agents, e.g., viruses, and theoretically, the Creutzfeldt-Jakob disease (CJD) agent. ( 5.5 )

5.1 Risk of Phlebitis A large arm vein or a central venous catheter should be utilized for the administration of PANHEMATIN to minimize the risk of phlebitis. Since reconstituted PANHEMATIN is not transparent, any undissolved particulate matter is difficult to see when inspected visually. Therefore, terminal filtration through a sterile 0.45 micron or smaller filter is recommended. [See Dosage and Administration ( 2.2 )]

5.2 Iron and Serum Ferritin Because increased levels of iron and serum ferritin have been reported in post-marketing experience, physicians must monitor iron and serum ferritin in patients receiving multiple administrations of PANHEMATIN [See Adverse Reactions ( 6.2 )] . In case of elevated iron or serum ferritin levels, consider iron chelation therapy.

5.3 Anticoagulant Effects Because PANHEMATIN has exhibited transient, mild anticoagulant effects during clinical studies, avoid concurrent anticoagulant therapy. The extent and duration of the hypocoagulable state induced by PANHEMATIN has not been established.

5.4 Renal Effects Recommended dosage guidelines should be strictly followed. Reversible renal shutdown has been observed in a case where an excessive hematin dose (12.2 mg/kg) was administered in a single infusion. Oliguria and increased nitrogen retention occurred although the patient remained asymptomatic. No worsening of renal function has been seen with administration of recommended dosages of hematin.

5.5 Transmissible Infectious Agents Because PANHEMATIN is made from human blood, it may carry a risk of transmitting infectious agents, e.g., viruses, the variant Creutzfeldt-Jacob disease (vCJD) agent, and theoretically the Creutzfeldt-Jacob disease (CJD) agent. The risk that this product may transmit an infectious agent has been reduced by screening blood donors for prior exposure to certain viruses, by testing for the presence of certain current virus infections, and by inactivating certain viruses. Despite these measures, this product can still potentially transmit disease. There is also the possibility that unknown infectious agents may be present in the product. All infections thought by a physician possibly to have been transmitted by this product should be reported by the physician or other healthcare provider to Recordati Rare Diseases at 1-888-575-8344.

The most common adverse reactions (occurring in >1% of patients) are: headache, pyrexia, infusion site reactions, and phlebitis. Most common adverse reactions in >1% of patients are headache, pyrexia, infusion site reactions, and phlebitis. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Recordati Rare Diseases Inc. at 1-888-575-8344 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials 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. The safety of PANHEMATIN use was evaluated in a compassionate use study. A total of 130 patients were treated with hemin for acute attacks, prophylaxis or both. Of those, 111 patients were administered hemin for treatment of 305 acute porphyria attacks and to 40 patients for prophylaxis. The majority (92%) of patients were Caucasian. Most (72%) were female; all adult patients had a mean age ± SD of 40.3 ± 12.3 years. Proportionally more females (15 out of 19) received prophylaxis or a combination of acute treatment and prophylaxis (19 out of 21). For the treatment of acute attacks, patients received 2 to 4 mg/kg/day PANHEMATIN intravenously for 1 to 9 doses. For prophylaxis patients, the most common doses were weekly or biweekly infusions. Table 1 summarizes adverse reactions occurring in >1% of patients treated with PANHEMATIN, categorized by body system and order of decreasing frequency. Table 1: Adverse Reactions in >1% of Patients Treated with PANHEMATIN System Organ Class Preferred Term Adverse Events N (% of Total Adverse Events) Description Total Possibly or Probably Related to Treatment Infections and infestations Cellulitis 3 (1.5%) 2 (1.0%) Nervous System Disorders Headache 18 (9.2%) 5 (2.6%) Vascular Disorders Phlebitis / Injection site phlebitis 7 (3.6%) 6 (3.1%) Skin and subcutaneous tissue disorders Rash 3 (1.5%) 3 (1.5%) General Disorders and Administration Site Conditions Pyrexia 9 (4.6%) 6 (3.1%) Catheter-related Complication 7 (3.6%) 3 (1.5%)

6.2 Postmarketing Experience The following adverse reactions associated with the use of PANHEMATIN were identified in open-label clinical trials or postmarketing reports. Because these reactions were reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency reliably or to establish a causal relationship to drug exposure. Blood and Lymphatic System Disorders: thrombocytopenia, coagulopathy (including prolonged prothrombin time and prolonged partial thromboplastin time), and hemolysis Immune System Disorders: hypersensitivity reactions including a report of infusion-related anaphylactoid reaction presenting as circulatory collapse Vascular Disorders: injection site venous thrombosis including some that occurred in large veins such as venae cavae General Disorders and Administration Site Conditions: infusion site reactions (such as erythema, pain, bleeding and extravasation) Metabolism and Nutrition Disorders: iron overload and serum ferritin increased [See Warnings and Precautions ( 5.2 )]

PANHEMATIN therapy is intended to limit the rate of porphyria/heme biosynthesis possibly by inhibiting the enzyme δ-aminolevulinic acid synthetase 1 (ALAS1) [See Clinical Pharmacology ( 12.1 )] . Most of the heme synthesized in liver is used for the production of cytochrome P450 (CYP) enzymes. Therefore, avoid CYP inducing drugs (such as estrogens, barbituric acid derivatives and steroid metabolites) while on PANHEMATIN therapy, because these drugs increase the activity of ALAS leading to induction of ALAS1 through a feedback mechanism. Avoid CYP inducing drugs such as estrogens, barbituric acid derivatives and steroid metabolites which induce δ-aminolevulinic acid synthetase 1 (ALAS1) through a feedback mechanism. ( 7 )

8.1 Pregnancy Risk Summary About 50% of the women with acute intermittent porphyria experience an acute attack of porphyria in pregnancy and/or the puerperium. It is most severe in early pregnancy and the puerperium, and can result in fatal outcome. Although anecdotal evidence suggests safe use of hematin during pregnancy, the available human data is not sufficient to establish the presence or absence of drug-associated risk. Animal reproduction studies have not been conducted with hematin. It is also not known whether hematin can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. PANHEMATIN should be given to a pregnant woman only if clearly needed. Avoid administering hematin in severe pre-eclampsia because of a theoretical risk of potentiation of the coagulation disorder [see Warnings and Precautions ( 5.3 )] . In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.

8.2 Lactation Risk Summary It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, the developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for PANHEMATIN and any potential adverse effects on the breastfed child from PANHEMATIN or from the underlying maternal condition.

8.4 Pediatric Use Safety and effectiveness in pediatric patients under 16 years of age have not been established.

8.5 Geriatric Use Clinical data for subjects aged 65 and over was not sufficient to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in response 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.

Heme acts to limit the hepatic and/or marrow synthesis of porphyrin. This action is likely due to the inhibition of δ-aminolevulinic acid synthetase, the enzyme which limits the rate of the porphyrin/heme biosynthetic pathway. The exact mechanism by which hematin produces symptomatic improvement in patients with acute episodes of the hepatic porphyrias has not been elucidated. PANHEMATIN therapy for the acute porphyrias is not curative. After discontinuation of PANHEMATIN treatment, symptoms generally return although in some cases remission is prolonged. Some neurological symptoms have improved weeks to months after therapy although little or no response was noted at the time of treatment.