Peginterferon alfa-2a Disease Interactions

Proteinuria (rare), not associated with a decrease in serum protein, is the most common renal toxicity observed with interferon- alfa therapy. Increased BUN and serum creatinine levels, hematuria, acute renal failure and nephrotic syndrome have also been reported. Therapy with interferon alfa should be administered cautiously to patients with severe renal dysfunction. Renal function should be evaluated in all patients before initiation of interferon- alfa therapy. In addition, patients with any degree of renal impairment should be carefully monitored for laboratory abnormalities and decreased creatinine clearance. A reduced dose of medication is recommended in patients with low CrCl (less than 50 mL/min - 30 mL/min).

Antiviral interferons may exacerbate autoimmune disorders such as myositis, thyroiditis, systemic lupus erythematosus, rheumatoid arthritis, psoriasis, or autoimmune hepatitis. Therapy should be avoided or administered with extreme caution in patients with autoimmune disorders.

Hypertension, arrhythmias, angina, myocardial infarction, cardiomyopathy, and congestive heart failure have been reported during interferon therapy. Therapy with interferons should be administered with caution in patients with compromised cardiac function.

The use of peginterferons alfa are contraindicated in patients with autoimmune hepatitis.

Life-threatening or fatal neuropsychiatric reactions have been reported in patients receiving peginterferons alfa, including suicide, suicide ideation, homicidal ideation, depression, relapse of drug addiction, and drug overdose. These reactions have occurred in patients with and without previous psychiatric illness. These drugs should be used with extreme caution in patients with a history of depression. Other events reported include aggressive behavior, psychosis, hallucinations, bipolar disorder and mania. Patients should be monitored for any evidence of depression or other psychiatric symptoms, and they should be advised to report any signs or symptoms of depression or other changes in mood or behavior. In severe cases, therapy should be stopped immediately and psychiatric intervention should be instituted.

The use of peginterferons alfa are contraindicated in patients with hepatic decompensation (Child-Pugh score greater than 6, class B or C) in cirrhotic patients before treatment, and in patients with hepatic decompensation (Child-Pugh score greater or equal to 6) that have chronic hepatitis C coinfected with HIV.

Peginterferons alfa suppress bone marrow function and may result in severe cytopenias. Very rarely, it may be associated with aplastic anemia. These drugs should be used with caution in patients with baseline neutrophil counts less than 1,500 cells/mm3, with platelet counts less than 90,000 cells/mm3 or baseline hemoglobin less than 10 g/dL. It is advised that complete blood counts be obtained pretreatment and monitored routinely during therapy. Neutropenia and thrombocytopenia occur with greater incidence in patients coinfected with HIV.

Peginterferons alfa can cause or aggravate hypothyroidism, hyperthyroidism, hyperglycemia, hypoglycemia and diabetes mellitus. Treatment should be administered with caution on patients with these conditions. Treatment should not be initiated if the condition cannot be effectively treated by medication. Therapy should be discontinued if any of these conditions develops during treatment and it cannot be controlled with medication.

Decrease or loss of vision, retinopathy including macular edema, retinal artery or vein thrombosis, retinal hemorrhages and cotton wool spots, optic neuritis, papilledema, and serious retinal detachment can be induced or aggravated by alpha interferons. All patients should receive an eye examination at baseline and caution should be exercised in patients with preexisting ophthalmologic disorders. Patients should have periodic ophthalmologic exams during treatment.

Dyspnea, pulmonary infiltrates, pneumonia, bronchiolitis, pulmonary hypertension, and other pulmonary disorders resulting in respiratory failure and/or death may be induced or aggravated by alpha interferon therapy. Caution should be used when used in patients with preexisting pulmonary disorders.