Sunesis Pharm stock tumbles after drug developer announces results from cancer treatment study

MarketsAssociated Press

Shares of Sunesis Pharmaceuticals tanked Monday, wiping out all their gains for 2014 and then some, after the drug developer said its treatment for an aggressive form of blood cancer missed its main goal in late-stage testing.

A combination of vosaroxin and the chemotherapy drug cytarabine did not lead to a statistically significant improvement in overall survival when compared with patients who took cytarabine and a placebo, or fake drug, the company said.

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The drugmaker is testing vosaroxin, also known as Qinprezo, as a possible treatment for a form of acute myeloid leukemia, a cancer that generally afflicts older adults.

Sunesis said the research did show a clinically significant benefit in complete remission rates, which was a secondary goal.

Late-stage research is the last phase of clinical study before a drugmaker submits its product to regulators for approval. Sunesis said it will seek marketing approval from European regulators and also will meet with the U.S. Food and Drug Administration to determine the "appropriate regulatory path forward."

Shares of Sunesis Pharmaceuticals Inc. sank 64 percent, or $4.25, to $2.39 more than an hour before markets opened Monday.

The South San Francisco, California, company's stock had climbed more than 40 percent so far this year, as of Friday's close.