2.1 Recommended Dosing

• The recommended starting dose is 6 mcg/kg/week subcutaneously for 8 doses, followed by 3 mcg/kg/week subcutaneously for up to 5 years.
• Premedicate with acetaminophen 500 to 1000 mg orally 30 minutes prior to the first dose of SYLATRON and as needed for subsequent doses.
• The recommended starting doses of SYLATRON in patients with moderate or severe renal impairment or end-stage renal disease (ESRD) are listed in Table 1 [see Use in Specific Populations (8.7)]. No dose adjustment is needed for patients with a creatinine clearance (CLcr) > 50 mL/min/1.73m2.

2.2 Dose Modification Guidelines

Guidelines for Dose Modification provided below are based on the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE Version 2.0).

• Permanently discontinue SYLATRON for:
  • Persistent or worsening severe neuropsychiatric disorders
  • Grade 4 non-hematologic toxicity
  • Inability to tolerate a dose of 1 mcg/kg/wk
  • New or worsening retinopathy
• Withhold SYLATRON dose for any of the following:
  • Absolute Neutrophil Count (ANC) less than 0.5×109/L
  • Platelet Count (PLT) less than 50×109/L
  • ECOG PS greater than or equal to 2
  • Non-hematologic toxicity greater than or equal to Grade 3
• Resume dosing at a reduced dose (see Table 1) when all of the following are present:
  • Absolute Neutrophil Count (ANC) greater than or equal to 0.5×109/L
  • Platelet Count (PLT) greater than or equal to 50×109/L
  • ECOG PS 0-1
  • Non-hematologic toxicity has completely resolved or improved to Grade 1

2.3 Preparation and Administration

Reconstitute SYLATRON with 0.7 mL of Sterile Water for Injection, USP. The Sterile Water for Injection supplied contains 5 mL. Each vial of Sterile Water for Injection is intended for single dose. Discard any unused Sterile Water for Injection, USP.

• Swirl gently to dissolve the lyophilized powder. DO NOT SHAKE.
• Visually inspect the solution for particulate matter and discoloration prior to administration. Discard if solution is discolored, cloudy, or if particulates are present.
• Do not withdraw more than 0.5 mL of reconstituted solution from each vial.
• Administer SYLATRON subcutaneously. Rotate injection sites.
• If reconstituted solution is not used immediately, store at 2°-8°C (36°-46°F) for no more than 24 hours. Discard reconstituted solution after 24 hours. DO NOT FREEZE.
• For single-dose only. DISCARD ANY UNUSED PORTION.

5.1 Depression and Other Serious Neuropsychiatric Adverse Reactions

Peginterferon alfa-2b can cause life-threatening or fatal neuropsychiatric reactions. These include suicide, suicidal and homicidal ideation, depression, and an increased risk of relapse of recovering drug addicts. In the clinical trial, depression occurred in 59% of SYLATRON-treated patients and 24% of patients in the observation group. Depression was severe or life threatening in 7% of SYLATRON-treated patients compared with <1% of patients in the observation arm.

In post-marketing experience, neuropsychiatric adverse reactions have been reported up to 6 months after discontinuation of peginterferon alfa-2b. Based on post-marketing experience with peginterferon alfa-2b and interferon alfa-2b, treatment may also result in aggressive behavior, psychoses, hallucinations, bipolar disorders, mania, and encephalopathy.

Advise patients and their caregivers to immediately report any symptoms of depression or suicidal ideation to their healthcare provider. Monitor and evaluate patients for signs and symptoms of depression and other psychiatric symptoms every 3 weeks during the first 8 weeks of treatment and every 6 months thereafter. Monitor patients during treatment and for at least 6 months after the last dose of SYLATRON. Permanently discontinue SYLATRON for suicidal or homicidal ideation, aggressive behavior towards others, or other severe or persistent psychiatric symptoms; institute psychiatric intervention and follow-up as appropriate.

5.2 Cardiovascular Adverse Reactions

In the clinical trial, cardiac adverse reactions, including myocardial infarction, bundle-branch block, ventricular tachycardia, and supraventricular arrhythmia occurred in 4% of SYLATRON-treated patients compared with 2% of patients in the observation group. In post-marketing experience, hypotension, cardiomyopathy, and angina pectoris have occurred in patients treated with peginterferon alfa-2b.

Permanently discontinue SYLATRON for new onset of ventricular arrhythmia or cardiovascular decompensation.

5.3 Retinopathy and Other Serious Ocular Adverse Reactions

Peginterferon alfa-2b can cause decrease in visual acuity or blindness due to retinopathy. Retinal and ocular changes include macular edema, retinal artery or vein thrombosis, retinal hemorrhages and cotton wool spots, optic neuritis, papilledema, and serous retinal detachment may be induced or aggravated by treatment with peginterferon alfa-2b or other alpha interferons. In the clinical study, two SYLATRON-treated patients developed partial loss of vision due to retinal thrombosis (n=1) or retinopathy (n=1). The overall incidence of serious retinal disorders, visual disturbances, blurred vision, and reduction in visual acuity was <1% in both SYLATRON-treated patients and the observation group.

Perform an eye examination that includes assessment of visual acuity and indirect ophthalmoscopy or fundus photography at baseline in patients with preexisting retinopathy and at any time during SYLATRON treatment in patients who experience changes in vision. Permanently discontinue SYLATRON in patients who develop new or worsening retinopathy.

5.4 Hepatic Failure

Peginterferon alfa-2b, increases the risk of hepatic decompensation and death in patients with cirrhosis. Monitor hepatic function with serum bilirubin, ALT, AST, alkaline phosphatase, and LDH at 2 and 8 weeks, and 2 and 3 months following initiation of SYLATRON, then every 6 months while receiving SYLATRON. Permanently discontinue SYLATRON for evidence of severe (Grade 3) hepatic injury or hepatic decompensation (Child-Pugh score >6 [class B and C]) [see Contraindications (4)].

5.5 Endocrinopathies

Peginterferon alfa-2b can cause new onset or worsening of hypothyroidism, hyperthyroidism, and diabetes mellitus. In the clinical study, 1% of patients developed hypothyroidism; the overall incidence of endocrine disorders was 2% in SYLATRON-treated patients compared to <1% for patients in the observation group.

Obtain TSH levels within 4 weeks prior to initiation of SYLATRON, at 3 and 6 months following initiation, then every 6 months thereafter while receiving SYLATRON. Permanently discontinue SYLATRON in patients who develop hypothyroidism, hyperthyroidism or diabetes mellitus that cannot be effectively managed.

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 clinical practice.

The data described below reflect exposure to SYLATRON in 608 patients with surgically resected, AJCC Stage III melanoma. SYLATRON was studied in an open label, multicenter, randomized, observation controlled trial. The median age of the population was 50 years with 10% of patients 65 years or older, and 42% were female. Fourteen percent of patients completed the 5 year treatment schedule.

Patients randomized to SYLATRON were to receive total doses of 48 mcg/kg (6 mcg/kg subcutaneous once weekly for 8 doses), and 780 mcg/kg (3 mcg/kg subcutaneous once weekly until disease recurrence or for up to 5 years), as tolerated. The median total dose received was 42 mcg/kg (range: 6 to 78 mcg/kg) for the first 8 doses, and 136 mcg/kg (range: 1 to 774 mcg/kg) for doses 9 to 260.

Serious adverse events were reported in 199 (33%) patients who received SYLATRON and 94 (15%) patients in the observation group.

The most common adverse reactions experienced by SYLATRON-treated patients were fatigue (94%), increased ALT (77%), increased AST (77%), pyrexia (75%), headache (70%), anorexia (69%), myalgia (68%), nausea (64%), chills (63%), and injection site reaction (62%). The most common serious adverse reactions were fatigue (7%), increased ALT (3%), increased AST (3%), and pyrexia (3%) in the SYLATRON-treated group vs. <1% in the observation group for these reactions.

Thirty three percent of patients receiving SYLATRON discontinued treatment due to adverse reactions. The most common adverse reactions present at the time of treatment discontinuation were fatigue (27%), depression (17%), anorexia (15%), increased ALT (14%), increased AST (14%), myalgia (13%), nausea (13%), headache (13%), and pyrexia (11%). Adverse events that occurred in the clinical study at ≥ 5% incidence in the SYLATRON-treated group and with a greater incidence in patients receiving SYLATRON as compared to the observation group are presented in Table 4.

6.2 Immunogenicity

As with all therapeutic proteins, there is potential for immunogenicity. In a clinical study conducted in patients with melanoma, the incidence of binding antibodies to peg-interferon alfa-2b was approximately 35% (50/144 patients). Among the patients who tested positive for binding antibodies, one patient developed neutralizing antibodies. The impact of antibody formation on pharmacokinetics, safety and efficacy of peg-interferon alfa-2b could not be assessed based on limited available data.

The incidence of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors, including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to SYLATRON with the incidence of antibodies to other products may be misleading.

6.3 Postmarketing Experience

The following adverse reactions have been identified during post-approval use of peginterferon alfa-2b as monotherapy and in combination with ribavirin in chronic hepatitis C (CHC) patients. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Blood and Lymphatic System Disorders

pure red cell aplasia, thrombotic thrombocytopenic purpura

Cardiac Disorders

pericarditis

Ear and Labyrinth Disorders

hearing loss, vertigo, hearing impairment

Endocrine Disorders

diabetic ketoacidosis

Eye Disorders

Vogt-Koyanagi-Harada syndrome

Gastrointestinal Disorders

aphthous stomatitis, pancreatitis, colitis, tongue pigmentation

Infusion Reactions

angioedema, urticaria, bronchoconstriction

Immune System Disorders

systemic lupus erythematosus, erythema multiforme, thyroiditis, thrombotic thrombocytopenic purpura, idiopathic thrombocytopenic purpura, rheumatoid arthritis, interstitial nephritis, and systemic lupus erythematosus

Infections

sepsis, hepatitis B virus reactivation in HCV/HBV co-infected patients

Metabolism and Nutrition Disorders

hypertriglyceridemia

Musculoskeletal and Connective Tissue Disorders

rhabdomyolysis, myositis

Nervous System Disorders

seizures, memory loss, peripheral neuropathy, paraesthesia, migraine headache

Respiratory, Thoracic and Mediastinal Disorders

dyspnea, pulmonary infiltrates, pneumonia, bronchiolitis obliterans, interstitial pneumonitis, sarcoidosis, pulmonary hypertension, and pulmonary fibrosis

Skin and Subcutaneous Tissue Disorders

Stevens-Johnson syndrome, toxic epidermal necrolysis, psoriasis

Vascular Disorders

hypertension, hypotension, stroke

8.1 Pregnancy

8.2 Lactation

8.3 Females and Males of Reproductive Potential

8.4 Pediatric Use

Safety and effectiveness in patients below the age of 18 years have not been established.

8.5 Geriatric Use

Clinical studies of SYLATRON did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

8.6 Hepatic Impairment

SYLATRON has not been studied in patients with melanoma who have hepatic impairment. In patients treated for viral hepatitis, peginterferon alfa-2b treatment is contraindicated in those with moderate or severe hepatic impairment (Child-Pugh scores >6). Discontinue SYLATRON if hepatic decompensation (Child-Pugh scores >6) occurs during treatment. [See Contraindications (4) and Warnings and Precautions (5.4).]

8.7 Renal Impairment

Reduce the dose of SYLATRON by 25% in patients with moderate renal impairment (CLcr 30 to 50 mL/min/1.73m2) and 50% in patients with severe renal impairment (CLcr < 30 mL/min/1.73m2) or ESRD requiring dialysis [see Dosage and Administration (2.1)]. A study in subjects with varying degrees of renal impairment showed that the mean exposure (AUC) to peginterferon alfa-2b increased in subjects with moderate and severe renal impairment or ESRD requiring dialysis, as compared to subjects with normal renal function (CLcr > 80 mL/min/1.73m2) following a single 4.5 mcg/kg dose of peginterferon alfa-2b [see Clinical Pharmacology (12.3)].

12.1 Mechanism of Action

Peginterferon alfa-2b is a pleiotropic cytokine; the mechanism by which it exerts its effects in patients with melanoma is unknown.

12.3 Pharmacokinetics

The pharmacokinetics was studied in 32 patients receiving adjuvant therapy for melanoma with SYLATRON according to the recommended dose and schedule (6 mcg/kg/week for 8 doses, followed by 3 mcg/kg/week thereafter). At a dose of 6 mcg/kg/week once weekly, the geometric mean Cmax was 4.4 ng/mL (CV 51%) and the geometric mean AUCtau was 430 ng∙hr/mL (CV 35%) at week 8. The mean terminal half-life was approximately 51 hours (CV 18%). The mean accumulation from week 1 to week 8 was 1.7. After administration of 3 mcg/kg/week once weekly, the mean geometric Cmax was 2.5 ng/mL (CV 33%) and the geometric mean AUCtau was 228 ng∙hr/mL (CV 24%) at week 4. The mean terminal half-life was approximately 43 hours (CV 19%).

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity studies have not been conducted with SYLATRON. Neither peginterferon alfa-2b nor its components, interferon or methoxypolyethylene glycol, caused damage to DNA when tested in the standard battery of mutagenesis assays, in the presence and absence of metabolic activation.

Irregular menstrual cycles were observed in female cynomolgus monkeys given subcutaneous injections of 4239 mcg/m2 peginterferon alfa-2b alone every other day for 1 month (approximately 72 to 144 times the recommended weekly human dose based upon body surface area). These effects included transiently decreased serum levels of estradiol and progesterone, suggestive of anovulation. Normal menstrual cycles and serum hormone levels resumed in these animals 2 to 3 months following cessation of peginterferon alfa-2b treatment. Every other day dosing with 262 mcg/m2 (approximately 3.5 to 7 times the recommended weekly human dose) had no effects on cycle duration or reproductive hormone status. The effects of SYLATRON on male fertility have not been studied.

Storage:

SYLATRON should be stored at 25°C (77°F); excursions permitted to 15°-30°C (59-86°F) [see USP Controlled Room Temperature]. DO NOT FREEZE.