|MadSci Network: Medicine|
I'm sorry, Charles, but I can't speak to prostaglandins in particular. I can tell you that medicinal chemists are constantly working to identify structural analogs of known drugs that have either increased efficacy or reduced side effects. This work can be as simple as identifying a specific isomer in a mixture that has the desirable properties. One example of this is the release of Nexium (esomeprazole) by AstraZeneca to replace Prilosec (omeprazole) for the treatment of stomach acid release problems. Esomeprazole is simply the S isomer of omeprazole (this is reflected in the name). A more complicated example is the hunt for drugs that replace the hormone estrogen, known as selesctive estrogen receptor modulators (SERMs). Ideally, SERMs would recapitulate all the beneficial effects of estrogen in women (increased bone density, healthy cholesterol balance, relieve hot flashes) without the potentially dangerous ones (increased risk of breast and uterine cancer). Because of the potential for use not only in cancer therapy and prevention, but also in hormone replacement therapy in post-menopausal women, SERMs are a very active area of research. For a layman's introduction to the action of estrogen and SERMs, I recommend this site from the National Cancer Institute: http://r ex.nci.nih.gov/behindthenews/uest/uestcontents.htm
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