Tretinoin (tret' i noyn; all-trans-retinoic acid; Retin-A), a derivative of vitamin A, has been used for years for topical treatment of acne. More recently, it has also been used to improve the appearance of skin damaged by chronic exposure to the sun, although not approved for this indication by the US Food and Drug Administration.

Oxaprozin (Daypro -Searle), a propionic acid-derivative nonsteroidal anti-inflammatory drug (NSAID), has been approved by the US Food and Drug Administration for once-daily treatment of rheumatoid arthritis and osteoarthritis. Some of the NSAIDs previously marketed in the USA are listed in the table on page 16. Ibuprofen, naproxen, fenoprofen, ketoprofen, and flurbiprofen are also propionic acid derivatives. Piroxicam and nabumetone (Medical Letter, 34:38, 1992) are also approved for once-daily use, and indomethacin is available in an extended-release formulation that can be taken once...

Paclitaxel (Taxol - Bristol-Myers Squibb) is now available in the USA for treatment of metastatic ovarian cancer refractory to other drugs. The new drug is a natural product extracted in small amounts from the inner bark of the Western yew tree found mainly in the Pacific northwest (Taxus brevifolia). Efforts to synthesize the drug have been unsuccessful to date, but a semi-synthetic product (taxotere) prepared from the needles of European yews has shown some promise (R Pazdur et al, J Natl Cancer Inst, 89:1781, 1992), and a fungus (Taxomyces andreanae) growing on the Pacific yew was...

In a study of the interaction between alcohol and the calcium-channel blocker felodipine (Plendil), the grapefruit juice vehicle for the alcohol appeared to increase felodipine plasma concentrations. Subsequent studies have found that grapefruit juice increases plasma concentrations of several calcium-channel blockers and of some other drugs as well (DG Bailey et al, Clin Pharmacokinet, 26:91, 1994).

Glimepiride (Amaryl - Hoechst Marion Roussel), a new sulfonylurea similar to glyburide and glipizide (Medical Letter, 26:79, 1984), was recently marketed for treatment of patients with non-insulin-dependent diabetes mellitus (NIDDM) not controlled by diet and exercise. The new drug is the first sulfonylurea approved by the US Food and Drug Administration (FDA) for use concurrently with insulin.

Cilostazol, a phosphodiesterase III inhibitor that has been used in Japan since 1988, has been approved by the FDA for treatment on intermittent claudication due to occlusive peripheral arterial disease.

Two cholesterol-lowering margarines have been marketed in the USA.

Two controlled-release formulations of triptorelin (trip toe rel' in) pamoate, an agonist analog of human luteinizing hormone-releasing hormone (LHRH), are now available in the US for parenteral treatment of advanced prostate cancer. Trelstar Depot is given every 4 weeks and Trelstar LA every 12 weeks. Triptorelin has been available in some countries since 1986.

Patients with lung cancer may be asking their physicians about gefitinib (ge fi' tye nib; ZD1839; Iressa -- AstraZeneca), because it has been the subject of positive coverage in the media. An inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, this oral drug has not been approved by the FDA, but is in clinical trials in the US for treatment of non-small cell lung cancer (NSCLC) and some other solid tumors. Iressa was recently approved in Japan, and is available from the manufacturer on a "compassionate-use" basis in the US (800-236-9933).

Eplerenone (e pler' en one; Inspra - Pharmacia), an aldosterone receptor antagonist similar to spironolactone (Aldactone, and others), has been approved by the FDA, but not yet marketed, for treatment of hypertension. It has also been tried for treatment of heart failure.