Compared To Standard Therapies, Pixantrone Decreases Time To Achieve Complete Remission By 47% In Relapsed Aggressive Non-Hodgkin's Lymphoma

Phase III safety data underscores clinical benefit of pixantrone

SEATTLE, February 18, 2009 — Cell Therapeutics, Inc. (NASDAQ and MTA: CTIC) announced today that updated safety and efficacy data from the phase III trial of pixantrone provides further support for a robust clinical benefit for pixantrone when used as single agent therapy in the treatment of multiple relapsed aggressive non-Hodgkin's lymphoma (NHL). On an intent-to- treat analysis, pixantrone recipients who achieved a complete remission did so during the first 2 cycles of therapy, compared to 4 cycles among standard chemotherapy recipients, (1.9 months vs. 3.6 months, pixantrone vs. standard chemotherapy).

The duration of response in the patients was similar in the 37% of pixantrone patients who had either a partial or complete response compared to the 14% of comparator patients with a major response. However, the overall progression free survival (PFS) was significantly longer in the pixantrone arm (4.7 months vs. 2.6 months, hazard ratio = 0.6; p = 0.0074, pixantrone vs. standard chemotherapy).

Thirty-two percent (32%) of pixantrone patients received all 6 cycles s of therapy, with 84% receiving 5 of 6 cycles of treatment. Pixantrone recipients had a low incidence of severe neutropenia complicated by either fever or documented infections, or severe vomiting or diarrhea. Pixantrone patients also experienced a low incidence of hair loss, a very common side effect of other drugs in this class. Overall, the incidence of serious adverse events was similar between pixantrone and the control arm. The pixantrone patients had a higher incidence of leucopenia and neutropenia and numerically more severe cardiac events (4 vs 2) than in the control arm. Disease progression reported as an adverse event was less frequent in the pixantrone than in the control arm (1.5% vs. 13.4%).

"We were impressed to see that 84% of patients received at least 5 cycles of pixantrone therapy with a median total dose of 1,475 mg, despite having had significant prior therapy with doxorubicin, an agent in a similar class with cumulative cardiotoxicity,” noted Jack Singer, M.D., Chief Medical Officer at CTI. "The rapid time-to-response data coupled with the relatively low incidence of traditional anthracycline toxicities and a safety profile that compares favorably to standard chemotherapy, positions pixantrone to live up to the promise of providing patients with relapsed aggressive NHL a meaningful clinical benefit.”

CTI announced in November 2008 that it had achieved the primary efficacy endpoint of its phase III EXTEND (PIX301) trial of pixantrone (BBR2778). Patients randomized to treatment with pixantrone achieved a high rate of confirmed and unconfirmed complete remissions compared to patients treated with standard chemotherapy (14/70 (20.0%) for pixantrone arm compared to 4/70 (5.7%) for the standard chemotherapy arm, p = 0.02). No patient (0%) in the standard chemotherapy arm achieved a confirmed complete remission compared to 8/70 (11%) of pixantrone recipients.

CTI expects to begin submission of a rolling New Drug Application (NDA) and request priority review for pixantrone to treat relapsed aggressive non-Hodgkin's lymphoma ( NHL) in the first quarter of 2009. If granted priority review a decision on the NDA could occur before the end of 2009. The study received Special Protocol Assessment approval from the U.S. Food and Drug Administration (FDA) in 2004, and pixantrone has received fast track designation for this indication. About Pixantrone Pixantrone (BBR 2778), a DNA intercalating antitumor agent that contains an aza-anthracenedione molecular structure, differentiating it from anthracycline chemotherapy agents, was discovered by our scientists in Bresso, Italy. Pixantrone is a novel DNA major groove binder that contains an aza-anthracenedione molecular structure, differentiating it from anthracycline chemotherapy agents. Anthracyclines have been shown to be very active clinically in a number of tumor types, such as lymphoma, leukemia, and breast cancer. For these diseases, anthracycline-containing chemotherapy regimens are effective in first-line (initial) treatment. However, they may cause cumulative heart damage that limits lifetime dosage and does not allow for retreatment. Pixantrone has been designed to reduce the potential for heart damage compared to currently available anthracyclines or anthracenediones without a loss in anti-tumor or immunomodulatory activities. 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 www.CellTherapeutics.com.

This press release includes forward-looking statements 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 pixantrone include risks associated with preclinical and clinical developments in the biopharmaceutical industry in general and with pixantrone in particular including the potential failure of pixantrone to prove safe and effective for treatment of relapsed aggressive NHL as determined by the FDA, the Company's ability to continue to raise capital as needed to fund its operations, competitive factors, technological developments, costs of developing, producing and selling pixantrone, 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. Except as may be required by law, CTI does not intend to update or alter its forward-looking statements whether as a result of new information, future events, or otherwise.

###

Media Contact: Dan Eramian T: 206.272.4343 C: 206.854.1200 E: media@ctiseattle.com www.CellTherapeutics.com/press_room

Investors Contact: Ed Bell T: 206.282.7100 Lindsey Jesch Logan T: 206.272.4347 F: 206.272.4434 E: invest@ctiseattle.com www.CellTherapeutics.com/investors

Posted: February 2009

View comments

Hide
(web3)