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Critical Therapeutics Completes Phase II Clinical Trial for Zileuton Injection

LEXINGTON, Mass.--(BUSINESS WIRE)--Jun 2, 2008 - Critical Therapeutics, Inc. (Nasdaq: CRTX) today announced top-line results from its Phase II clinical trial of the injectable formulation of zileuton (zileuton injection), the Company's investigational compound for acute asthma in the emergency department (ED). The clinical trial was designed to explore the pulmonary function profile, safety, tolerability and pharmacokinetic profile of zileuton injection.

Asthma results in approximately two million ED visits and 500,000 hospitalizations each year in the U.S., according to the Allergy and Asthma Foundation of America. It is estimated that ED visits and hospitalizations for asthma account for more than 50 percent of the healthcare costs of the disease.

A total of 36 evaluable patients with stable chronic asthma were enrolled in the randomized, multi-center, double-blind, Phase II, three-period, crossover trial, which was designed to explore the pulmonary function profiles of subjects after receiving a single dose of zileuton injection compared to placebo in patients who were not experiencing an acute exacerbation of asthma. To qualify for inclusion in the trial, patients had to have a forced expiratory volume in one second (FEV1) of 40% to 80% of predicted normal and suspend use of some asthma controller medications prior to dosing. Patients were randomized to three treatment periods with two dose levels of zileuton injection (150 mg and 300 mg) and placebo. Pulmonary function was measured using the variables of FEV1 and peak expiratory flow rate (PEFR) at multiple time points over the first hour then hourly to 360 minutes after dosing.

Zileuton injection, at both dose levels, was well tolerated in all 36 patients and there were no serious adverse events reported.

Patients at each of the two zileuton injection dose levels showed a numerically greater mean percentage improvement in FEV1 from baseline than patients in the placebo group, however, the results were not statistically significant compared to placebo. A greater effect on pulmonary function was achieved at the 150 mg dose level of zileuton injection compared with the 300 mg dose level or placebo. This mean percentage improvement in FEV1 from baseline was evident from the first measurement time point of 10 minutes after dosing and was maintained for at least 240 minutes.

The Company believes that the variability in baseline levels of FEV1 seen within individual patients across the three dosing occasions often resulted in higher-than-expected baseline lung function, which did not provide an opportunity to achieve a meaningful improvement in lung function that could approach statistical significance. Exploratory analyses conducted on the study data indicate that patients with lower pulmonary function at baseline (baseline FEV1 less than or equal to 65% of predicted normal) responded better to zileuton treatment. The Company believes that these exploratory analyses and the tolerability of zileuton injection may support a clinical trial in an acute population as a potential next step in the development process. The Company intends to initiate a process to seek to enter into a collaboration agreement for the future clinical development and commercialization of zileuton injection.

Data on the pharmacokinetic profile at each dose level of zileuton injection will be obtained from population pharmacokinetic analysis, which is nearing completion.

"We believe zileuton injection represents a significant therapeutic opportunity for the treatment of acute asthma in the ED," said Trevor Phillips, Ph.D., the Company's president and chief executive officer. "By delivering zileuton directly to the bloodstream, the injectable formulation has the potential to have a rapid onset of action and may lead to faster symptom relief when used in conjunction with current therapies. We believe that this trial, together with the data from the previous Phase I/II clinical trial, indicates that zileuton injection may have a beneficial effect on pulmonary function in chronic stable asthma patients and supports future development of zileuton injection in acute asthma patients."

About Critical Therapeutics, Inc.

Critical Therapeutics, Inc. is developing and commercializing innovative products for respiratory and inflammatory diseases. Critical Therapeutics owns worldwide rights to two FDA-approved drugs: ZYFLO CR(TM) (zileuton) extended-release tablets and ZYFLO(R) (zileuton tablets). Critical Therapeutics is developing products for acute asthma attacks that lead patients to the emergency room and other urgent care settings. Critical Therapeutics also is developing therapies directed toward the body's inflammatory response. Critical Therapeutics is located in Lexington, Mass. For more information, please visit

Forward-Looking Statements

Any statements in this press release about future expectations, plans and prospects for Critical Therapeutics, Inc., including, without limitation, statements regarding possible therapeutic opportunities for and the potential efficacy of zileuton injection; the progress and timing of additional results from the Phase II clinical trial of zileuton injection; our strategy, future operations, financial position, future revenues, and projected costs; prospects, plans and objectives of management; and all other statements that are not purely historical in nature, constitute "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Without limiting the foregoing, the words "anticipate," "believe," "could," "estimate," "expect," "intend," "may," "plan," "project," "should," "will," "would" and similar expressions are intended to identify forward-looking statements. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including risks and uncertainties relating to: final results of the Phase II clinical trial of zileuton injection and possible future development plans; our ability to achieve and sustain compliance with all NASDAQ listing requirements; our ability to successfully market and sell ZYFLO CR, including the success of our co-promotion arrangement with DEY; our ability to transition our management team effectively; our ability to develop and maintain the necessary sales, marketing, distribution and manufacturing capabilities to commercialize ZYFLO CR; patient, physician and third-party payor acceptance of ZYFLO CR as a safe and effective therapeutic product; adverse side effects experienced by patients taking ZYFLO CR or ZYFLO; our heavy dependence on the commercial success of ZYFLO CR; our ability to maintain regulatory approvals to market and sell ZYFLO CR; the success of our co-promotion arrangement with DEY for Perforomist(TM) (formoterol fumarate) Inhalation Solution; our ability to successfully enter into additional strategic co-promotion, collaboration or licensing transactions on favorable terms, if at all; conducting clinical trials, including difficulties or delays in the completion of patient enrollment, data collection or data analysis; the results of preclinical studies and clinical trials with respect to our products under development and whether such results will be indicative of results obtained in later clinical trials; our ability to obtain the substantial additional funding required to conduct our development and commercialization activities; our dependence on our strategic collaboration with MedImmune, Inc.; and our ability to obtain, maintain and enforce patent and other intellectual property protection for ZYFLO CR, our discoveries and our drug candidates. These and other risks are described in greater detail in the "Risk Factors" section of our Quarterly Report on Form 10-Q and other filings that we make with the Securities and Exchange Commission. If one or more of these factors materialize, or if any underlying assumptions prove incorrect, our actual results, performance or achievements may vary materially from any future results, performance or achievements expressed or implied by these forward-looking statements.

In addition, the statements in this press release reflect our expectations and beliefs only as of the date of this release. We anticipate that subsequent events and developments will cause our expectations and beliefs to change. However, while we may elect to update these forward-looking statements publicly at some point in the future, we specifically disclaim any obligation to do so, except as required by law, whether as a result of new information, future events or otherwise. In general, our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, business development transactions, or joint ventures, except that in particular circumstances as specifically indicated we may address the potential impact of our proposed transaction with Cornerstone BioPharma Holdings, Inc. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this release.

ZYFLO(R) is a registered trademark of Critical Therapeutics, Inc.

ZYFLO CR(TM) is a trademark of Critical Therapeutics, Inc.

Perforomist(TM) is a trademark of Dey, L.P.


Critical Therapeutics, Inc.
Linda S. Lennox, 781-402-5708
Vice President, Investor & Media Relations

Posted: June 2008