EXHIBIT 99.1
Contact:
Investors: Media:
Ann Tanabe Brad Miles
Encysive Pharmaceuticals BMC Communications
(713) 796-8822 (212) 477-9007 ext. 17
Hershel Berry
The Trout Group
(415) 392-3385
FOR IMMEDIATE RELEASE
NEW DATA ON THELIN(TM) PRESENTED AT
AMERICAN THORACIC SOCIETY'S INTERNATIONAL CONFERENCE
THREE ABSTRACTS PRESENTED FROM STRIDE-1 AND EXTENSION TRIALS
WEBCAST TO BE HELD MONDAY, MAY 24, 2004 AT 9:30 AM EDT
HOUSTON, TX- MAY 24, 2004- Encysive Pharmaceuticals (NASDAQ: ENCY) today
announced that investigators presented data from clinical studies of Thelin(TM)
(sitaxsentan) in pulmonary arterial hypertension (PAH), at the American Thoracic
Society's (ATS) 100th International Conference in Orlando, Florida. The data,
presented on Sunday, May 23, was collected as part of Encysive's pivotal Phase
IIb/III STRIDE-1 (Sitaxsentan To Relieve ImpaireD Exercise) clinical trial and
extensions.
"These data from STRIDE-1 and its extensions continue to support our strategy to
evaluate Thelin in the broadest population ever for this drug class," said Bruce
D. Given, M.D., President and Chief Executive Officer of Encysive
Pharmaceuticals. "The data presented here support our belief that even earlier
stage patients can benefit with Thelin therapy. In addition, Dr. David
Langleben's long-term data and the functional class data from STRIDE-1 and its
extensions suggest that patients may continue benefiting from Thelin with
chronic therapy."
The first abstract, "Chronic Sitaxsentan in Pulmonary Arterial Hypertension" (E.
Horn, et al.), analyzed STRIDE-1 and extension data to assess the time course to
clinical improvement or deterioration with Thelin at doses of 100 mg and 300 mg.
Following treatment with a mean duration of 26 weeks and a maximum of 58 weeks,
53% of patients on 100 mg and 44% of patients on 300 mg improved at least one
New York Heart Association (NYHA) functional class. A substantial portion of
those individuals that improved did so within the initial 12 weeks of therapy -
64% and 70% for 100 mg and 300 mg patients, respectively. During the first 12
weeks, liver function abnormalities greater than three times the upper limit of
normal occurred in 0% for 100 mg and 10% for 300 mg, with overall rates of 5%
for 100 mg and 21% for 300 mg reported during the entire treatment course.
During treatment, only 5% of patients experienced NYHA functional class
deterioration on 100 mg and 8% on 300 mg. While both doses of Thelin
are similarly effective in improving functional class, both short- and
long-term, the more favorable safety/efficacy profile of 100 mg lends further
support to its selection as the maximum clinical dose in ongoing trials of
Thelin(TM).
The second abstract, entitled "Sustained Clinical and Functional Benefit in
Patients with Pulmonary Arterial Hypertension After One Year of Therapy with the
Selective, Orally-Active Endothelin-A Receptor Antagonist, Sitaxsentan" (D.
Langleben, et al.), reported that Thelin significantly improved NYHA functional
class and six-minute walk distance (6MW) in PAH patients after one year of drug
therapy. Of the 11 patients studied, nine were categorized as functional class
III and two as class II, when assessed prior to therapy. Although one patient's
health deteriorated at seven months, the other 10 continued to either improve to
or remain at class II at one year. For those 10 patients, the 6MW improved from
385 meters to 436 meters after one year of treatment (p=0.04).
The final study, "6MW as an Efficacy Endpoint in PAH Clinical Trials:
Demonstration of a Ceiling Effect" (A. Frost, et. al.), supports the existence
of a "ceiling effect" as provided for in traditional PAH trial designs. This
explains the frequent exclusion of patients with milder PAH, in order to
increase treatment effect sizes and statistical power when using 6MW as the
endpoint. STRIDE-1, a 12-week, randomized, double-blind, 178-patient trial
employing placebo and Thelin at 100 mg or 300 mg doses, included patients with
NYHA functional class II, congenital heart disease and a baseline 6MW >
450m-groups often excluded from previous trials. For patients meeting
traditional enrollment criteria (NYHA class III or IV and 6MW=450m at baseline
with idiopathic PAH or PAH-related to connective tissue disease), Thelin
produced a robust increase in 6MW of 65 meters (p=0.0002) vs. 34 meters
(p=0.0005) in the intent to treat patient group.
ATS WEBCAST INFORMATION
Encysive Pharmaceuticals will host a webcast in conjunction with the American
Thoracic Society's (ATS) International Conference on Monday, May 24 at 9:30 am
EDT, hosted by Dr. Bruce Given. The webcast will be available on the Company's
website, www.encysive.com, with an accompanying slide presentation, through June
24, 2004.
ABOUT THELIN(TM) AND PAH
Thelin is a small molecule that blocks the action of endothelin, a potent
mediator of blood vessel constriction and growth of smooth muscle in vascular
walls. Endothelin receptor antagonists may prove to be effective in the
treatment of a variety of diseases where the regulation of vascular constriction
is important. Thelin is 6,500 fold selective in the targeting of the endothelin
A receptor.
Pulmonary arterial hypertension (PAH) is a condition that involves high blood
pressure and structural changes in the walls of the pulmonary arteries, which
are the blood vessels that connect the right side of the heart to the lungs. PAH
causes shortness of breath, limits activity, and is eventually fatal unless
treated successfully with heart and lung transplant. Primary and secondary PAH
are estimated to afflict approximately 80,000 to 100,000 people worldwide, many
of whom are children and young women.
Side effects of Thelin(TM) seen in the program to date, and which occurred more
frequently than in placebo, include liver dysfunction (increased ALT and AST),
headache, edema, constipation, nasal congestion and flushing. Because Thelin
inhibits the metabolism of warfarin, the dose of warfarin should be adjusted
downward when co-administered with Thelin.
ABOUT ENCYSIVE PHARMACEUTICALS
Encysive Pharmaceuticals Inc., a biopharmaceutical company focused on the
discovery, development and commercialization of novel drugs, is recognized for
our expertise in small molecule drug development and vascular biology.
Argatroban, our first FDA-approved product, is being marketed by GlaxoSmithKline
for heparin-induced thrombocytopenia. Encysive Pharmaceuticals is in Phase III
development of the endothelin antagonist, Thelin, for pulmonary arterial
hypertension. Our majority-owned affiliate, Revotar Biopharmaceuticals AG, is in
Phase II development with the selectin antagonist bimosiamose in asthma,
psoriasis and atopic dermatitis. Encysive Pharmaceuticals has several other
research and development programs ongoing for a range of cardiovascular and
inflammatory diseases. To learn more about Encysive Pharmaceuticals please visit
our web site: www.encysive.com.
This press release contains "forward-looking statements" within the meaning of
Section 27A of the Securities Act of 1933, as amended, and Section 21E of the
Securities Exchange Act of 1934, as amended. These forward-looking statements
are subject to certain risks, trends and uncertainties that could cause actual
results to differ materially from those projected. Among those risks, trends and
uncertainties are timing and cost of our clinical trials, attainment of research
and clinical goals and milestones of product candidates, attainment of required
government approvals, sales levels of our products and availability of financing
and revenues sufficient to fund development of product candidates and
operations. In particular, careful consideration should be given to cautionary
statements made in the various reports Encysive Pharmaceuticals, including as
Texas Biotechnology Corporation, has filed with the Securities and Exchange
Commission. The Company undertakes no duty to update or revise these
forward-looking statements.
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