Pegintron

Pegintron is a brand name for pegylated interferon alfa-2b, a long-acting form of the cytokine interferon alfa-2b. Pegylation attaches polyethylene glycol to interferon, increasing its size and reducing renal clearance, which extends its half-life and allows less frequent dosing. The drug is used in the management of chronic hepatitis C and has been employed in certain cancer treatment regimens.

Medical use and indications: In hepatitis C, pegylated interferon alfa-2b is used in combination with ribavirin as part of antiviral therapy. It has also been used as adjuvant or primary therapy in select cancers, though the advent of newer antiviral agents has reduced its role for hepatitis C in many settings. The exact use and dosing depend on the specific indication, patient factors, and evolving treatment guidelines.

Pharmacology and mechanism: Interferon alfa-2b possesses antiviral, antiproliferative, and immunomodulatory properties. Pegylation prolongs circulating levels, enabling a more convenient dosing schedule and more sustained activity.

Administration and dosing: Pegintron is administered by subcutaneous injection, typically on a weekly basis. Dosing is determined by indication, body weight, and clinical response, with adjustments guided by monitoring.

Safety and adverse effects: Common adverse effects include flu-like symptoms (fever, fatigue, myalgias), injection-site reactions, cytopenias, and weight loss. Psychiatric symptoms such as depression or irritability, thyroid dysfunction, and hepatic enzyme elevations can occur. More serious but less frequent events include infections or autoimmune phenomena. Contraindications include hypersensitivity to interferons, decompensated liver disease, certain autoimmune conditions, and, in some cases, pregnancy. Regular monitoring of blood counts, liver function, and mood is recommended during treatment.

See also: Pegasys, another pegylated interferon used for similar indications.