| Item |
Information |
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Drug Groups
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approved |
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Description
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An antineoplastic agent that is a derivative of progesterone and used to treat advanced breast cancer. [PubChem] |
| Indication |
For palliative treatment of advanced breast cancer in postmenopausal women. |
| Pharmacology |
Testolactone is a synthetic anti-neoplastic agent that is structurally distinct from the androgen steroid nucleus in possessing a six-membered lactone ring in place of the usual five-membered carbocyclic D-ring. Despite some similarity to testosterone, testolactone has no in vivo androgenic effect. No other hormonal effects have been reported in clinical studies in patients receiving testolactone. |
| Toxicity |
Oral LD50s in mouse and dog are 1630 mg/kg and 593-926 mg/kg, respectively. |
| Affected Organisms |
| • |
Humans and other mammals |
|
| Biotransformation |
Hepatic. Metabolized to several derivatives in the liver, all of which preserve the lactone D-ring. |
| Absorption |
Testolactone is well absorbed from the gastrointestinal tract. |
| Protein Binding |
~85% |
| Elimination |
No clinical effects in humans of testolactone on adrenal function have been reported; however, one study noted an increase in urinary excretion of 17-ketosteroids in most of the patients treated with 150 mg/day orally. It is metabolized to several derivatives in the liver, all of which preserve the lactone D-ring. These metabolites, as well as some unmetabolized drug, are excreted in the urine. |
| External Links |
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