MOUNTAIN VIEW, Calif., June 9 /PRNewswire-FirstCall/ -- AlexzaPharmaceuticals, Inc. (Nasdaq: ALXA) announced today preliminary results fromits Phase 2a proof-of-concept clinical trial with AZ-002 (Staccato(R)alprazolam) in patients with panic disorder. The study did not meet its twoprimary endpoints, which were the effect of AZ-002 on the incidence of adoxapram-induced panic attack and the effect of AZ-002 on the duration of adoxapram-induced panic attack, both as compared with placebo. There were noserious adverse events in the clinical trial, and AZ-002 was safe and welltolerated in the study patient population. AZ-002 is being developed throughSymphony Allegro, a development collaboration formed between Alexza andSymphony Capital LLC in 2006.

The Company also announced today, in a separate news release, that it hascompleted enrollment of its first Phase 3 clinical trial with AZ-004 (Staccatoloxapine)for the treatment of acute agitation in patients with schizophreniaor bipolar disorder. Alexza will host an investor conference call to discusstoday's announcements on Monday, June 9, 2008 at 5:15 p.m. Eastern Time.

'The failure to reach statistical significance on the primary endpoints isdisappointing, but this proof-of-concept clinical trial was designed tocapture data and measurements for a number of clinical parameters in thisclinical setting,' said James V. Cassella, PhD, Senior Vice President,Research and Development at Alexza and chairman of the Symphony AllegroDevelopment Board. 'There is no FDA-approved therapy for the acute treatmentof a panic attack or an established clinical development pathway for thispotential new indication. We plan to work with our colleagues at SymphonyAllegro and our external clinical experts to further analyze the data fromthis study to determine our next steps with AZ-002.'

AZ-002 Phase 2a Clinical Trial Design

The AZ-002 Phase 2a clinical trial was an in-clinic, randomized,double-blind, placebo-controlled proof-of-concept evaluation of patients withpanic disorder. After an open-label pilot phase, 40 patients were enrolled at3 U.S. clinical centers, with 20 patients receiving 1 mg AZ-002 and 20patients receiving Staccato placebo. The primary aim of the clinical trialwas to assess the safety and efficacy of a single dose of AZ-002 in treating apharmacologically-induced panic attack.

Two primary endpoints were prospectively defined for the study, one toassess the effect of treatment on the occurrence of a doxapram-induced panicattack of sufficient intensity and a second to assess the effect of treatmenton the duration of the doxapram-induced panic attack.