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Selective estrogen receptor modulators for postmenopausal osteoporosis: current state of development
Luigi Gennari1, Daniela Merlotti, Fabrizio Valleggi
1Department of Internal Medicine, Endocrine-Metabolic Sciences and Biochemistry, University of Siena, Policlinico Le Scotte, Siena, Italy. gennari@unisi.it
Drugs & Aging
|May 17, 2007
Summary
Selective estrogen receptor modulators (SERMs) offer versatile treatments for aging conditions like osteoporosis and cancer. New SERMs show promise for improved efficacy and safety, with ongoing trials to confirm therapeutic potential.
Area of Science:
- Pharmacology and Endocrinology
- Oncology
- Geriatrics
Background:
- Selective estrogen receptor modulators (SERMs) are a versatile drug class targeting intracellular estrogen receptors.
- Current SERMs like tamoxifen and raloxifene treat breast cancer and osteoporosis but have serious side effects.
- Existing SERMs are less potent than estrogen, necessitating the search for improved alternatives.
Purpose of the Study:
- To review the therapeutic applications and limitations of current SERMs.
- To explore the development and potential of novel SERMs for osteoporosis and related conditions.
- To highlight the ongoing research for an 'ideal' SERM with enhanced efficacy and safety.
Main Methods:
- Literature review of preclinical and clinical studies on SERMs.
- Analysis of drug mechanisms, efficacy, and adverse effect profiles.
- Examination of ongoing clinical trials for new SERM candidates.
Main Results:
- Tamoxifen and toremifene are used for breast cancer and show benefits in bone density and lipids.
- Raloxifene is approved for postmenopausal osteoporosis prevention and treatment.
- Newer SERMs (ospemifene, lasofoxifene, bazedoxifene, arzoxifene) demonstrate potential for greater efficacy and improved safety profiles in preclinical models.
Conclusions:
- Current SERMs provide benefits but carry risks like thromboembolic disorders and uterine cancer.
- The development of novel SERMs aims to achieve estrogenic effects on bone/lipids, neutral effects on the uterus, and antiestrogenic effects on the breast.
- Further clinical data from ongoing trials are crucial to establish the therapeutic value and safety of new SERM agents.
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