Washington Editor

Synta Pharmaceuticals Corp. is trying again for an initial public offering, proposing a $115 million stock sale to further fund its product development efforts.

The biopharmaceutical firm, of Lexington, Mass., has yet to specify the number of shares to be sold, and it has not set its indicative range. But in its latest filing with the SEC, Synta said it has applied to list the stock on the Nasdaq Global Market as "SNTA."

Its previous IPO attempt was registered nearly two years ago, when it also initially sought $115 million. In April 2005, it set a range of $14 to $16 per share for 6 million shares, which would have brought in $90 million if the IPO priced in the middle of that range. A month later, it postponed the offering. (See BioWorld Today, Jan. 20, 2005.)

The company plans to spend a large portion of its proceeds on a pivotal trial of its lead compound, STA-4783, in metastatic melanoma.

A Phase IIb study that tested paclitaxel with the injectable small molecule, which induces a stress response in cancer cells, showed that the combination produced a statistically significant response on progression-free survival, its primary endpoint.

Specifically, median progression-free survival totaled 3.68 months for patients treated with STA-4783 and paclitaxel compared to 1.84 months for those treated solely with paclitaxel (p=0.035). In addition, the percentage of patients who survived and were free of tumor progression at six months more than doubled, from 15 percent for patients treated with paclitaxel alone to 35 percent in those treated with the combination.

The FDA, which has designated STA-4783 a fast-track product in that indication, has suggested that progression-free survival is an acceptable endpoint for registration in metastatic melanoma, and Phase III is scheduled to begin next year. Synta also plans to begin Phase II studies of the same compound in other indications at the same time. Past Phase II trials have explored its use in non-small-cell lung cancer and soft-tissue sarcoma.

Additional funds would go toward further studies of apilimod (STA-5326), depending on Phase IIa results in rheumatoid arthritis and common variable immunodeficiency. Data are due next year on the oral small molecule, which inhibits the production of interleukin-12 and interleukin-23 to down-regulate inflammation pathways that underlie certain autoimmune and inflammatory diseases.

Other proceeds are tabbed for Synta's preclinical research candidates: STA-9090, an inhibitor of heat-shock protein 90 for cancer; STA-9584, a compound designed to disrupt blood vessels that supply tumors with oxygen and nutrients; as well as unnamed inhibitors of calcium release-activated calcium ion channels expressed on immune cells.

The company also plans to use proceeds to fund general and administrative expenses, working capital needs and other general corporate purposes potentially related to complementary technologies, products or companies.

Founded in July 2001 with roots in Shionogi BioResearch Corp., a U.S.-based drug discovery subsidiary of Osaka, Japan-based Shionogi & Co. Ltd., Synta has raised more than $200 million in private financing to date. Most recently, the company closed a $40 million round over the summer.

Its top shareholders include Lan Bo Chen, a co-founder and director; President and CEO Safi Bahcall, another co-founder; and the venture capital firm CxSynta LLC in Princeton, N.J. Synta had $58.7 million in cash, cash equivalents and marketable securities as of Sept. 30.