Biomedical subjects

D R Kohler

Publications and source records attributed to D R Kohler.

21 records · Page 2Linked to original sources

PubMed1990

Flutamide: an antiandrogen for advanced prostate cancer.

Flutamide is a nonsteroidal pure antiandrogen that acts by inhibiting the uptake and/or binding of dihydrotestosterone to the target cell receptor, thus interfering with androgen action. Flutamide is well absorbed orally and extensively metabolized; its active metabolite, 2-hydroxyflutamide, is formed rapidly and excreted almost entirely by the kidneys. Clinical studies in prostate cancer patients have demonstrated efficacy with flutamide monotherapy in patients who had received no prior treatment, in untreated patients with combined androgen blockade concomitantly with a luteinizing hormone-releasing hormone (LHRH)-agonist, and in relapsed patients. A randomized, placebo-controlled trial demonstrated a 26 percent increase in median survival for patients treated with leuprolide plus flutamide compared with leuprolide plus placebo. When given as monotherapy and in combination with an LHRH-agonist, flutamide is well tolerated. The usual adverse effects are gynecomastia and mild diarrhea when given as a single agent. In combination with an LHRH-agonist, hot flashes, loss of libido, impotence, mild nausea and vomiting, gynecomastia, and diarrhea are commonly reported. However, only diarrhea occurred more frequently in patients treated with leuprolide plus flutamide than in those treated with leuprolide plus placebo. Flutamide is indicated in combination with an LHRH-agonist (e.g., leuprolide) as initial therapy in metastatic (stage D2) prostate cancer. The usual dose is 250 mg po tid given at eight-hour intervals and started concurrently with the LHRH-agonist. Formulary addition is recommended.

Anilides↗

PubMedDate not supplied

Paclitaxel (taxol).

Paclitaxel is a novel antineoplastic that effects cytotoxicity by promoting intracellular tubulin polymerization and stabilizes abnormal microtubule structures against depolymerization. Although its clinical development had been hampered by misconceptions about its pharmacology, its scarcity, difficulties extracting it from its natural source, formulation problems, and frequent severe hypersensitivity reactions, paclitaxel recently was approved for treatment-refractory ovarian cancer. Two major adverse effects are dosage- and schedule-related myelosuppression and mucositis. Neurotoxicity is directly related to both the individual and cumulative doses. Other relevant toxicities are hypersensitivity reactions, effects on cardiac rate and rhythm, arthralgias and myalgias, generalized hair loss, and mild nausea and emesis. Continuing clinical studies will evaluate paclitaxel as initial therapy for ovarian cancer and its utility in other malignancies. In addition, major efforts are under way to develop alternative sources to increase the availability of taxene analogs and reduce our dependence on yew species.

Clinical Trials as Topic↗

PubMedDate not supplied

Goserelin acetate implant: a depot luteinizing hormone-releasing hormone analog for advanced prostate cancer.

Goserelin acetate implant is a newly approved depot formulation of a luteinizing hormone-releasing hormone (LHRH) agonist indicated for palliation of advanced prostate cancer. LHRH superagonists suppress gonadotropin release from the pituitary gland by causing down-regulation of receptors. The sustained-release dosage form contains goserelin acetate dispersed in a biodegradable copolymer matrix and is designed to release active drug over 28 days. Pharmacokinetic studies have demonstrated that, despite nonzero order release of goserelin from the matrix, goserelin acetate implant maintains serum concentrations of testosterone in the range normally found in castrated men (less than 2 nmol/L) throughout the recommended 28-day dosing interval. Response rates similar to those for orchiectomy and estrogen administration have been demonstrated. Combination therapy with either diethylstilbestrol or flutamide has produced favorable results, although the major advantage appears to be a reduction in the tumor flare seen during the first week of LHRH agonist therapy rather than an increase in response rate or survival. Adverse effects are similar to other LHRH agonists and include tumor flare during the first week of therapy, decreased libido, decreased erectile potency, hot flashes, and gynecomastia. In combination with flutamide, additional adverse effects include diarrhea, nausea, vomiting, and elevated hepatic aminotransferases, all of which can be attributed to flutamide administration. Local reactions are minimal; however, some patients require a local anesthetic before goserelin acetate implant injection. The recommended dose is 3.6 mg administered subcutaneously into the upper abdominal wall every 28 days. The average wholesale cost is approximately +320 per month. Formulary addition is recommended.

Amino Acid Sequence↗