Critical Therapeutics Announces Efficacy Data for Controlled-Release Formulation of Zileuton Presented at ACAAI 2006 Annual Meeting.

Zileuton CR Demonstrated a Statistically Significant Reduction in Need for Inhaled Beta Agonist and Provided Early and Sustained Improvement in Lung Function

LEXINGTON, Mass. -- Critical Therapeutics (Nasdaq: CRTX) today announced the presentation of three posters at the American College of Allergy, Asthma and Immunology (ACAAI) 2006 Annual Meeting in Philadelphia. Two posters highlighted efficacy data for the twice daily, controlled-release formulation of zileuton (zileuton CR). The third poster reviewed data showing zileuton's impact on inflammation in a preclinical model of asthma. Zileuton CR, an investigational drug, is a 5-lipoxygenase (5-LO) inhibitor designed to block the production of 5-LO, an enzyme responsible for asthma symptoms. The Company submitted its New Drug Application (NDA) for zileuton CR to the U.S. Food and Drug Administration (FDA) on July 31, 2006. The Prescription Drug User Fee Act (PDUFA) date is currently scheduled for May 31, 2007. Pending regulatory approval, the Company expects to launch zileuton CR in the second half of 2007.

The two zileuton CR posters contained efficacy data derived from a 16-week randomized, double-blind, multi-center, placebo-controlled clinical trial in a total of 613 asthma patients. Patients were not on any chronic asthma treatment other than inhaled beta-agonists and were randomized into 1 of 4 treatment groups: zileuton CR 1200 mg taken twice daily or placebo CR; zileuton immediate-release (IR) 600 mg taken four-times daily or placebo IR for 12 weeks. In this clinical trial, zileuton CR demonstrated a significant reduction in the use of inhaled beta agonists and provided early and sustained improvement in pulmonary function compared with placebo CR. Harold Nelson, M.D., of the National Jewish Medical and Research Center, Denver, Colorado, and Stanley Fineman, M.D. of Emory University School of Medicine, Atlanta, Georgia, were lead authors on the two posters.

Zileuton CR Provided Early and Sustained Reductions in Beta-Agonist Use

Data in Dr. Nelson's poster noted that patients receiving zileuton CR demonstrated an early (Days 1-22) and sustained (Days 72-92) reduction in beta-agonist use. From Days 1-22, zileuton CR patients experienced a mean reduction from baseline of 0.41 (pen0.001) in the daily number of times they used an inhaler, compared with a mean reduction of 0.13 in the placebo CR group. From Days 72-92, the mean reduction from baseline was 0.54 in the zileuton CR group (pen0.050), compared with a mean reduction of 0.26 in the placebo CR group.

In the same clinical trial, investigators examined the number of inhaler puffs. Patients treated with zileuton CR experienced a mean reduction from baseline of 0.90 (pen0.001) from Days 1-22, compared with a mean reduction of 0.16 in the placebo CR group. From Days 72-92, the mean reduction was 0.96 (pen0.010) in the zileuton CR group, compared with a mean reduction of 0.31 in the placebo CR group.

Zileuton CR Provided Early and Sustained Improvement in Pulmonary Function

Data in Dr. Fineman's poster noted that improvements in forced expiratory volume in one second (FEV1), a measurement of lung function, were significant as early as Day 15 versus placebo (pen0.001) and were sustained throughout the trial (pen0.050). Patients treated with zileuton CR experienced a mean improvement in FEV1 of 0.23 liters at Day 15, compared with 0.09 liters in the placebo group. At Day 85, the mean improvement in FEV1 was 0.39 liters in the zileuton group, compared with 0.27 liters in the placebo group.

Zileuton Inhibits the Infiltration of Eosinophils and Neutrophils (Murine Model)

The third poster presented at ACAAI provided data demonstrating that zileuton inhibits the infiltration of both neutrophils and eosinophils and reduces systemic immunoglobulin E (IgE) in a mouse model of allergic lung inflammation. Asthma exacerbations, acute severe asthma and rapid onset fatal asthma have been associated with neutrophil predominance. IgE, which occurs naturally in the body, is increased in allergies and asthma and plays an important role in asthma. Increased airway eosinophils were reduced at 8 hours in the zileuton and montelukast treatment groups. However, neutrophils were largely inhibited by zileuton (90.0%) and only modestly by montelukast (30.6%). IgE levels in serum samples showed that zileuton significantly reduced IgE levels, while montelukast had no effect on systemic IgE.

About ZYFLO([R])/Zileuton

ZYFLO([R]) (zileuton tablets) is indicated for the prevention and chronic treatment of asthma in adults and children 12 years of age and older. Zileuton inhibits 5-lipoxygenase (5-LO), an enzyme that catalyzes the formation of leukotrienes from arachidonic acid. 5-LO is the main enzyme responsible for the production of leukotrienes, a family of inflammatory mediators that can trigger asthma symptoms, including inflammation, swelling, bronchoconstriction and mucus secretion. ZYFLO is the only 5-LO inhibitor approved for marketing by the U.S. Food and Drug Administration.

ZYFLO is not indicated for use in the reversal of broncospasm in acute asthma attacks, including status asthmaticus. Mild to moderate side effects associated with the use of ZYFLO are abdominal pain, upset stomach and nausea. A small percentage of patients treated with ZYFLO show an increased release of a liver enzyme known as ALT. As a result, the level of liver enzymes in patients treated with ZYFLO should be measured by a simple blood test. It is recommended that physicians perform this test before administering ZYFLO and repeat the test on a regular basis while patients are on the medication. ZYFLO is contraindicated in patients with active liver disease or transaminase elevations greater than or equal to three times the upper limit of normal. For full prescribing information, please visit www.crtx.com/pat_pi.html or call the Company's toll free telephone number 1-866-835-8216 to request medical information.

About ACAAI

The ACAAI is a professional medical organization comprising nearly 5,000 qualified allergists-immunologists and related health care professionals. Established in 1942, the ACAAI is dedicated to improving the quality of patient care in allergy, asthma and immunology through research, advocacy and professional public education.

About Critical Therapeutics

Critical Therapeutics, Inc. is developing and commercializing innovative products for respiratory, inflammatory and critical care diseases. The Company owns worldwide rights to ZYFLO[R] (zileuton tablets), which is marketed in the United States for the prevention and chronic treatment of asthma in patients 12 years of age and older. Critical Therapeutics is working to expand its zileuton franchise by introducing a twice daily, controlled-release formulation for the prevention and chronic treatment of asthma and an intravenous formulation for acute asthma attacks that lead patients to the emergency room and other urgent care settings. The Company also is collaborating with MedImmune, Inc. to design antibody therapies that treat acute and chronic diseases triggered by the inflammatory cytokine HMGB1. Research pipeline programs include lifecycle management to extend the zileuton franchise and an alpha-7 project for the treatment of inflammation. Critical Therapeutics is located in Lexington, Mass. For more information, please visit www.crtx.com.

Forward-Looking Statements

Any statements in this press release about future expectations, plans and prospects for Critical Therapeutics, Inc., including, without limitation, all 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: whether the results referred to in this release will be interpreted by the U.S. Food and Drug Administration or patients, physicians and third-party payers in the same manner as the Company; 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; the expected timing and outcome of the NDA for zileuton CR and related discussions with the FDA; the extent of market acceptance of the Company's products; the Company's heavy dependence on the commercial success of ZYFLO and, if approved, zileuton CR; our ability to maintain regulatory approvals to market and sell ZYFLO and, if approved, zileuton CR; adverse side effects experienced by patients taking ZYFLO and the Company's other zileuton product candidates; our ability to enter into collaborative agreements and other third party agreements to develop, commercialize, market or sell our products; conducting clinical trials, including difficulties or delays in the completion of patient enrollment, data collection or data analysis; our ability to obtain the substantial additional funding required to conduct our research, development and commercialization activities; and our ability to obtain, maintain and enforce patent and other intellectual property protection for ZYFLO, our drug candidates and our discoveries. These and other risks are described in greater detail in the "Risk Factors" section of our most recent 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 release reflect our expectations and beliefs 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, whether as a result of new information, future events or otherwise. 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.