New Uses for Old Drugs
Often, drugs that treat more than one condition do so by acting on the same biological pathway, or target.
Often, drugs that treat more than one condition do so by acting on the same biological pathway, or target. Aspirin, for example, blocks production of prostaglandins, which not only cause aches and soreness by sensitizing pain receptors and inducing inflammation but also raise the risk of heart attack by causing platelets to clot. But some multitalented drugs appear to hit more than one target, sometimes leading to very different uses.
ORIGINAL USE |
NEW USE |
|
Astemizole |
Allergic rhinitis Treats hay fever and other allergies by blocking histamine, which promotes nasal and bronchial mucus |
Malaria Kills malaria-causing parasites that are resistant to usual therapy; under study |
Rocephin(ceftriaxone) |
Various infections Acts as an antibacterial and is useful in treating infections of the lower respiratory tract, urinary tract, ear, and others |
Amyotrophic lateral sclerosis and other neurological diseases Appears to lower levels of the neurotransmitter glutamate; under study |
Evista(raloxifene) |
Osteoporosis Activates estrogen receptors in bones, lending greater strength and density |
Breast cancer Blocks estrogen receptors in breast tissue, preventing the hormone from promoting tumor growth |
Sporanox(itraconazole) |
Fungal infections Kills organisms that cause a variety of fungal infections, such as aspergillosis, blastomycosis, histoplasmosis and candidiasis |
Cancer May destroy blood vessels that feed tumors; under study |
Rheumatrex(methotrexate) |
Cancer Blocks the enzyme involved in the growth of malignant cells |
Rheumatoid arthritis and other autoimmune disorders Reduces inflammation, possibly by decreasing excessive immune system activity |
Thalidomide |
Morning sickness Acted as a sedative in a formulation prescribed to pregnant women before being banned for causing birth defects |
Multiple myeloma Appears to slow the growth of tumor cells and to prevent bone marrow destruction |
Born Again
Creating a medicine from scratch takes years and may cost $1 billion. One alternative: recycling failed compounds for new applications.
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