Preclinical Study Shows CTI's Brostallicin's Cancer-Killing Ability Based on Genetic Profiling

SAN DIEGO, April 15 /PRNewswire-FirstCall/ -- Systems Medicine LLC (SM), a wholly owned subsidiary of Cell Therapeutics, Inc. (CTI) (Nasdaq and MTAX: CTIC), presented data from a preclinical study demonstrating that the Company's experimental drug candidate, brostallicin, killed colon and ovarian cancer cells regardless of their p53 status. The study, conducted by Cristina Geroni, Ph.D., et al of Nerviano Medical Sciences in Milan, Italy suggests that while brostallicin is more effective in cells with normal p53 status, cells with abnormal or missing p53 are also killed when treated. P53 is a protein that regulates the cell cycle and acts as a tumor suppressor. Patient tumors that have low or absent p53 are less responsive to standard therapy and have a worse prognosis.

"The results of this study support the further clinical development of brostallicin. They also provide deeper insight into brostallicin's context of vulnerability concerning different types of p53 protein, and where it is most effective. In our continued efforts to make cancer more treatable, results like these increase our understanding of cancer and potential therapies, and bring us closer to being able to offer the right drugs to the right patients," said Jeffrey Jacob, CEO of SM.

This study examined brostallicin's effect on cell viability, cell cycle modulation, and the initiation of cell death in cancer cell models with either normal (also referred to as wild-type) or abnormal (mutated or absent) p53 tumor suppressor. These results were supported through tests in animal models, where brostallicin demonstrated a statistically significant effect on suppressing tumor growth. To review the poster and see more detailed information about the study, please go to http://www.celltherapeutics.com/investors_news-updates.htm.

About Brostallicin

Brostallicin, a novel synthetic second-generation DNA minor groove binder, has potent cancer killing activity and has demonstrated synergism in combination with standard cytotoxic agents as well as with newer targeted therapies in preclinical experimental tumor models. Brostallicin binds covalently to DNA within the DNA minor groove, interfering with DNA division and leading to tumor cell death. More than 200 patients have been treated with brostallicin in single-agent and combination studies. Brostallicin had predictable and predominantly hematologic toxicities. Activity was demonstrated in a number of solid tumor types. A phase II study of brostallicin in relapsed/refractory soft tissue sarcoma met its pre-defined activity and safety hurdles and resulted in a first-line phase II study that is currently being conducted by the European Organization for Research and Treatment of Cancer (EORTC).

About Systems Medicine (SM)

In July 2007, CTI acquired Systems Medicine (SM), a privately held oncology company, in a stock-for-stock merger. SM applies a systems biology approach to drug development, combining pharmacogenomics and bioinformatics with experienced preclinical, clinical, and regulatory expertise to find and exploit a specific cancer's 'context of vulnerability.' Specifically, SM defines the molecular and genetic alterations (context) that cause cancer cells to be particularly sensitive (vulnerable) to a drug or combination of drugs -- the 'context of vulnerability'.

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.

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 brostallicin include risks associated with preclinical and clinical developments in the biopharmaceutical industry in general and with brostallicin in particular including, without limitation, the potential failure of the preclinical results to predict results in clinical trials, the potential failure of brostallicin to prove safe and effective for treatment of solid tumors particularly ovarian or colon cancers, determinations by regulatory, patent and administrative governmental authorities, competitive factors, technological developments, costs of developing, producing and selling brostallicin, 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.

SOURCE Cell Therapeutics, Inc.