Syndax snags $26.6M round for Phase III breast cancer study

Waltham, MA-based Syndax Pharmaceuticals took a big step to the threshold of a key pivotal study for its lead cancer therapy today, completing a $26.6 million venture round. The funds will pay for a Phase III study of entinostat, an HDAC inhibitor which promises to extend the efficacy of a standard breast cancer therapy.

The money should give Syndax enough cash to harvest the data from the Phase III study, says CEO Arlene Morris, who took the reins at the biotech after leaving a now struggling Affymax ($AFFY). The National Cancer Institute is paying much of the freight for the Phase III trial, she adds, which will help take a significant amount of the burden off Syndax. And the ECOG-ACRIN Cancer Research Group will conduct the study. But the company would still require additional cash to do CMC work and the rest of the effort needed to complete an NDA.

To complete this round, Domain Associates brought in their Russian partners at RusnanoMedInvest and they were joined by MPM Capital and Forward Ventures. Domain founded the company with technology developed at the Salk Institute.

The Phase III study should get started in the first quarter of next year, Morris tells FierceBiotech.

The biotech has yet to settle on just how many breast cancer patients will be selected for the study, though Morris says it should be larger than the 125 patients recruited for a successful Phase II trial. In that study patients whose metastatic breast cancer was progressing on a hormone therapy were divided into two groups. One group was treated with daily doses of exemestane--an aromatase inhibitor--and a weekly round of entinostat and the other received a placebo on top of exemestane. The combo arm saw median progression-free jump from 2.3 months to 4.3 months while overall survival--an exploratory endpoint--jumped to 28.1 months compared to 19.8 months in the placebo arm.

The idea here is that entinostat can delay the advance of the cancer and also push back the need for chemotherapy, which has a harsh impact on patients.

Syndax, a 2007 Fierce 15 company, has quietly reached an advanced stage for an epigenetics company focused on gene regulation. Prior to this round, Syndax had already raised at least $55 million in venture cash, though Morris said she couldn't say exactly how much the company has raised in total. The biotech has typically been run by a virtual staff, though Morris says that the roster of fewer than a dozen employees will grow now as the company jumps into Phase III.

- here's the press release

Special Report: Syndax Pharmaceuticals - 2007 Fierce 15