MM-398 - Biotech's 5 key attacks on pancreatic cancer

October 13, 2011 — 9:26am ET | By Ryan McBride  There are no approved therapies for patients with metastatic pancreatic cancer who fail treatment with the chemo drug gemcitabine. Potentially brightening the prospects for these patients, Merrimack Pharmaceutical's MM-398 has shown some promise in a mid-stage study and the developer now plans to usher the nano-drug into Phase III trial by the end of the year. The Cambridge, MA-based company's candidate is a formulation of the approved chemo drug irinotecan that is encapsulated in tiny liposomal particles to improve its properties for fighting cancer. In a recent single-arm Phase II trial, 40 pancreatic cancer patients on the drug had a median overall survival of 22.4 weeks. And one in 5 survived for more than a year, the company says. A sizable, $17 million to $22 million chunk of the firm's planned $172 million IPO would go toward the Phase III trial, which is expected to enroll 250 patients with metastatic pancreatic cancer and compare MM-398 with an existing treatment for this population that includes the chemo drugs 5-FU and leucovorin, according to an SEC filing. The trial will go a long way in determining whether Merrimack's drug will advance to the market for pancreatic cancer, and whether patients with limited options will have a new approved weapon against the aggressive tumors. After seeing the upbeat Phase II data on the drug, Merrimack went out and secured the Asian and European rights to the drug in May from PharmaEngine, which retained only rights to the experimental drug in Taiwan. Then, in July, the FDA granted the company orphan status for the treatment for the firm's target subset of pancreatic cancer patients, giving the firm 7 years of market exclusivity if the treatment is approved for this use. Merrimack, which is developing the drug for a variety of tumor types, gained ownership of the asset through its 2009 buyout of Hermes BioSciences, the candidate's original developer.