Alexza Pharma shares tank on FDA's safety concerns about Adasuve

Investors appeared to get worried after FDA staffers cited worries about lung safety issues with Alexza Pharmaceuticals' ($ALXA) inhaled anti-agitation drug Adasuve. Shares of the developers stock were down 47.47% yesterday, with the safety concerns potentially slimming the odds that the drug will gain U.S. approval for patients with schizophrenia or bipolar disorder as hoped early next year.

Pulmonary safety risks were among the concerns that sunk Alexza's last attempt to gain FDA approval of the drug in fall 2010. The recent FDA staff review said the drug appeared to be effective in reducing agitation in patients, but the reviewers were unsatisfied that the company had answered lingering questions about the risk of airway threats to patients who take the treatment, Reuters reported.

Alexza's drug offers the convenience of an inhaled therapy for a condition that now gets treated with a menu of injected drugs, and bringing the therapy quickly into the bloodstream via the lungs could also be beneficial, yet regulators have a track record of harping on safety issues of drugs despite such advantages. With the harsh critique of the drug in the FDA staff review, investors appeared to flee from Alexza's stock ahead of a Feb. 4 action date on the developer's application for approval.

But if the FDA approval of the sleep drug Intermezzo--a reformulated Ambien treatment that was twice rejected by the agency--taught us anything last month, persistence and perseverance in drug development can pay off eventually.

- check out Reuters' coverage
- and Bloomberg's article