Merck stops lead PDE-4 study

Phase II development of lead phosphodiesterase-4 inhibitor compound for asthma, COPD discontinued, company announces April 25. Merck, which was developing a once-daily oral formulation under a collaborative agreement with Celltech, says it continues to study other PDE-4 inhibitor molecules for asthma and COPD, although "the timing for the development of these other molecules is not certain." Merck has demonstrated success with backup compounds where initial lead agents have failed in clinical trials - Singulair was a successor product to Venzair, Merck's first leukotrine antagonist asthma candidate whose development was halted due to clinical toxicity...