The News

Cell Therapeutics, Inc. Completes Enrollment in Second Pivotal Trial of XYOTAX™ in Poor Performance Status (PS2), Non-Small Cell Lung Cancer Patients

25/05/2004

Single largest randomized trial ever conducted in PS2 patients

May 25, 2004 Seattle—Cell Therapeutics, Inc. (CTI) (Nasdaq: CTIC) announced that it has completed enrollment in STELLAR 4 at a total of 122 sites across the United States, Europe, and Latin America. The trial is one of three phase III studies that CTI is conducting in non-small cell lung cancer (NSCLC) and the single largest randomized study conducted in poor performance status (PS2) lung cancer patients. The study compares XYOTAX™ (paclitaxel poliglumex) at a paclitaxel equivalent dose of 175 mg/m2 to gemcitabine (1000mg/m2) or vinorelbine (30mg/m2) in PS2 NSCLC patients. The primary endpoint of the study is to determine if XYOTAX improves the survival of PS2 patients when compared to single-agent gemcitabine or vinorelbine therapy. Reported trials of gemcitabine or vinorelbine have not demonstrated a survival benefit in PS2 non small cell lung cancer patients.

“We are pleased with the rapid rate of enrollment in this trial, despite increasing the sample size by approximatley 96 patients as a result of modifying the study protocol last October. I believe the enrollment rate is a testament to the interest among lung cancer specialists who recognize that PS2 patients need more tolerable and effective therapies,” noted Jack W. Singer, M.D. and Chief Medical Officer at CTI. “Like all of our STELLAR pivotal trials the primary analysis is event rate driven and as such we would not expect top line data to be reported until early in the first quarter of 2005. As we are experiencing with STELLAR 3, which completed enrollment last November, the encouragingly slow event rate has pushed the time to analyze data from that trial from August to October. We are all cautiously optimistic about this trend."

In November 2002, based on Special Protocol Assessment (SPA) acceptance from the Food and Drug Administration (FDA), CTI initiated two phase III trials of XYOTAX for the potential front-line treatment of PS2 patients with NSCLC. Following its review of the proposed study design for the STELLAR trials, the FDA indicated that the choice of the PS2 population and the primary trial endpoints were acceptable. In June 2003, XYOTAX received fast track designation from the FDA for the PS2 non-small cell lung cancer pivotal trials for having the potential to address an unmet medical need.

About PS2 NSC Lung Cancer
PS2 patients represent a subgroup of patients who are ambulatory and capable of self-care, but are unable to carry out any work activities, although they are up and about more than 50 percent of waking hours. PS2 NSCLC patients account for approximately 25% of all patients with NSCLC who require chemotherapy. Current treatments for this group of patients are poorly tolerated, with most tolerating a median of two doses of chemotherapy and experiencing disease progression on average within six weeks. Current treatments also have limited effectiveness, with median survival ranging from only ten weeks for single-agent treatment to just over 17 weeks for combination therapies. Preliminary results of a phase II clinical study of XYOTAX™ (175mg/m2) demonstrated the drug was well tolerated with 50 percent of patients receiving four or more doses of therapy and 30 percent receiving six or more treatment cycles. Only one patient developed grade 4 neutropenia. Median survival among PS2 patients in that study was approximately 5.4 months.

About STELLAR Clinical Trials
STELLAR 2 is a phase III clinical trial of XYOTAX™ versus docetaxel for the potential second-line treatment of NSCL cancer patients.
STELLAR 3 is a phase III clinical trial of carboplatin in combination with either XYOTAX™ or paclitaxel for the potential front-line treatment of poor performance status (PS2) patients with NSCL cancer.
STELLAR 4 is a phase III clinical trial of XYOTAX™ versus either gemcitabine or vinorelbine for the potential front-line treatment of poor performance status (PS2) patients with NSCL cancer.

About XYOTAX™
XYOTAX™ (pronounced Zī-ō-tăks) is an investigational pharmaceutical that links paclitaxel, the active ingredient in Taxol®, to a biodegradable polyglutamate polymer. This polymer technology results in a new chemical entity, designed to selectively deliver higher and potentially more effective levels of active chemotherapeutics to tumors. Blood vessels in tumor tissue, unlike blood vessels in normal tissue, are porous to molecules like polyglutamate. Based on preclinical studies, it appears that XYOTAX™ is preferentially trapped in the tumor blood vessels allowing significantly more of the dose of chemotherapy to localize in the tumor.
Because more of the chemotherapy is targeted to the tumor and the levels of chemotherapy delivered to normal tissue are reduced, XYOTAX™ may be potentially more effective and have less severe side effects than currently available chemotherapeutics.

About Cell Therapeutics, Inc.
Based in Seattle, CTI is a biopharmaceutical company committed to developing an integrated portfolio of oncology products aimed at making cancer more treatable.

This announcement includes forward-looking statements relating to the development of the Company’s products and future clinical results that involve a number of risks and uncertainties, the outcome of which could materially and/or adversely affect actual future results. Specifically, the risks and uncertainties that could affect the development of XYOTAX™ include risks associated with preclinical and clinical developments in the biopharmaceutical industry in general and with XYOTAX™ in particular including, without limitation, the progress, costs, and results of the ongoing clinical trials, the potential failure of XYOTAX™ to prove safe and effective for treatment of non-small cell lung cancer, determinations by regulatory, patent and administrative governmental authorities, competitive factors, technological developments, costs of developing, producing and selling XYOTAX™, and the risk factors listed or described from time to time in the Company’s filings with the Securities and Exchange Commission including, without limitation, the Company’s most recent filings on Forms 10-K, 8-K, and 10-Q.

 

For further information please contact:

Investors
Cell Therapeutics, Inc.
Leah Grant
T: 206.282.7100 F: 206.272.4010
E: invest@ctiseattle.com
www.cticseattle.com/investors.htm

Media
Cell Therapeutics, Inc.
Candice Douglass
T: 206.272.4472 F: 206.272.4010
E: media@ctiseattle.com
www.cticseattle.com/media.htm
Cell Therapeutics, Inc. (Europe)
Karl Hanks
T: 39 026 103 5807 F: 39 026 103 5601
E: karl.hanks@ctimilano.com