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Updated: Jun 4, 2026

Bronchial Thermoplasty: A Novel Therapeutic Approach to Severe Asthma
Published on: November 4, 2010
Discovery of a potent, orally bioavailable pyrimidine VLA-4 antagonist effective in a sheep asthma model
Christopher M Semko1, Linda Chen, Darren B Dressen
1Elan Pharmaceuticals, Inc., S. San Francisco, CA 94080, USA. semko@sbcglobal.net
Abstract:
A series of N-(pyrimidin-4-yl)-phenylalanine VLA-4 antagonists is described. Optimization of substituents at the 2 and 5 positions of the pyrimidine ring gave 14, a very potent VLA-4 inhibitor which is orally active in a sheep asthma model.
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