GOG Says Continuation of Pivotal OPAXIO Maintenance Therapy Trial (GOG-212) Remains High Priority

Gynecologic Oncology Group (GOG) Notifies CTI That Continuation of GOG-212 Pivotal Trial of OPAXIO Maintenance Therapy in Front Line Ovarian Cancer Remains High Priority.  GOG-218 Bevacizumab Results Do Not Influence Importance of GOG-212

Cell Therapeutics, Inc. (“CTI”) announced today that the company received a statement on March 1, 2010 from the Gynecologic Oncology Group (GOG) leadership that the phase III GOG-212 clinical trial of CTI’s OPAXIO™ (formerly known as Xyotax or CT-2103) used as maintenance therapy for ovarian cancer remains a high priority and enrollment will continue. The GOG made the statement to clarify that the recent results of the GOG-218 clinical trial bevacizumab in maintenance therapy for ovarian cancer has not influenced the importance of completing the GOG-212 clinical trial. The Gynecologic Oncology Group (GOG) is one of the National Cancer Institute’s (NCI) funded cooperative cancer research groups. The GOG is a multidisciplinary cooperative clinical trial research group focused on the study of gynecologic malignancies. The GOG is conducting phase III trials in ovarian cancer and other gynecologic cancers and has established standard treatments for these diseases in the U.S.

GOG leadership noted the following:

GOG-218 and GOG-212 differ in the type of patients under study. It is important to note that some of the patients who completed the initial 6 cycles of chemotherapy in GOG-218 had clinical evidence of persistent tumor and were randomized to either placebo (no treatment) or bevacizumab [Avastin®]. Thus a subset of GOG-218 patients received no therapy, despite the presence of persistent tumor. This is not the typical setting of using maintenance or consolidation therapy and it is not the setting for patients enrolled in GOG-212. In GOG-212, only patients who have achieved a complete clinical response are considered candidates for enrollment in the trial.

Reliance upon the data from GOG-218 to establish the “standard of care” must take into consideration the actual treatment effect (i.e., duration of benefit), the cost of the treatment, and the associated toxicity… [in GOG-212] the toxicity of the intervention may have less associated mortality and the incremental cost-effectiveness ratio may be more acceptable to patients and the health care economists. Thus the GOG has no intention to discontinue enrollment in GOG 212 as they feel that the study is addressing a different scientific question and the primary outcome study goal is survival, not progression free survival, an outcome of greater importance to both physicians and patients.

The Data Monitoring Committee is scheduled to conduct an interim analysis of overall survival when 130 events are recorded among patients in the no maintenance treatment arm. The statistical analysis plan utilizes pre-specified boundaries for early stopping for success. Based on current enrollment and study duration, the interim analysis could be conducted as early as 2011. If successful, CTI could utilize those results to form the basis of its New Drug Application for OPAXIO.

About Cell Therapeutics, Inc.

Headquartered in Seattle, CTI is a biopharmaceutical company committed to developing an integrated portfolio of oncology products aimed at making cancer more treatable. For additional information, please visit http://www.celltherapeutics.com/.

Sources:

• Gynecologic Oncology Group (GOG) Notifies CTI That Continuation of GOG-212 Pivotal Trial of OPAXIO Maintenance Therapy in Front Line Ovarian Cancer Remains High Priority — GOG-218 Bevacizumab Results Do Not Influence Importance of GOG-212, Cell Therapeutics, Inc., March 4, 2010.

• A Randomized Phase III Trial of Maintenance Chemotherapy Comparing 12 Monthly Cycles of Single Agent Paclitaxel or Xyotax (CT-2103) (IND# 70177), Versus No Treatment Until Documented Relapse in Women With Advanced Ovarian or Primary Peritoneal or Fallopian Tube Cancer Who Achieve a Complete Clinical Response to Primary Platinum/Taxane Chemotherapy, Gynecologic Oncology Group, Study ID Numbers: CDR0000422427, GOG-0212 [ClinicalTrials.gov ID: NCT00108745].

• Genentech Announces Positive Results of Avastin Phase III Study in Women with Advanced Ovarian Cancer, by Paul Cacciatore, Libby’s H*O*P*E*™, February 25, 2010.