The FDA has approved peginterferon alfa-2b (Sylatron – Merck) for adjuvant treatment of node-positive melanoma after surgical resection. Pegylated interferon has a longer duration of action than interferon alfa-2b (Intron A), which is also FDA-approved for adjuvant treatment of malignant melanoma after surgery, and can be given once a week, compared to 3-5 times a week for standard interferon.

Recombinant interferon alfa-2b conjugated to polyethylene glycol (PEG-Intron), the first "pegylated"alpha interferon, has been approved by the FDA for once-a-week monotherapy of chronic hepatitis C virus (HCV) infection in patients not previously treated with alpha interferon.

The FDA has approved recombinant interferon alfa-2a conjugated to polyethylene glycol (Pegasys - Roche) alone or with oral ribavirin (Copegus - Roche) for treatment of adults with chronic hepatitis C virus (HCV) infections not previously treated with interferon alpha. The standard of care for treatment of most patients with hepatitis C has been once-weekly injections of peginterferon alfa-2b (PEG-Intron -Schering) plus oral ribavirin (Rebetol - Schering) (Medical Letter 2001; 43:54).

Rebetron, a combination of injected recombinant interferon alfa-2b with oral ribavirin has been approved by the FDA for treatment of chronic hepatitis C virus infection.

Recombinant alpha interferon has been marketed in the USA for treatment of hairy-cell leukemia, genital warts, and AIDS-related Kaposi's sarcoma (Medical Letter, 28:78, 1986; 30:70, 1988). Recent reports indicate it may also be useful for treatment of chronic viral hepatitis. Recombinant alpha interferon is available as alfa-2a (Roferon-A - Roche) or alfa-2b (Intron A - Schering), which are identical except for one amino acid.

Recombinant interferon alfa-2b (Intron A - Schering) was recently approved by the US Food and Drug Administration (FDA) for intralesional treatment of genital warts (condylomata acuminata). Interferon was previously available only for treatment of hairy-cell leukemia (Medical Letter, 28:78, 1986).

Temsirolimus (Torisel - Wyeth), an mTOR (mammalian target of rapamycin) kinase inhibitor that is metabolized to sirolimus (rapamycin), has been approved by the FDA for intravenous treatment of advanced renal cell carcinoma.

Sunitinib (Sutent - Pfizer) and sorafenib (Nexavar - Bayer), two oral tyrosine kinase inhibitors, have been approved by the FDA for treatment of advanced renal cell carcinoma (RCC). Sunitinib is also approved for use in patients with gastrointestinal stromal tumor (GIST) who are not responding to or are intolerant of standard therapy with imatinib (Gleevec).

Adefovir dipivoxil (Hepsera - Gilead), a nucleotide analog, has been approved by the FDA for oral treatment of chronic active infection with hepatitis B virus (HBV). In 1999, because of concerns about renal toxicity, the FDA rejected a higher-dosage formulation of adefovir for treatment of HIV infection.