SSF's Sunesis Pharmaceuticals, Inc. Believes It Can End 40 Year AML Drought Despite "Failed" Phase 3 Study
December 8, 2014
By Riley McDermid, BioSpace.com Breaking News Editor
South San Francisco-based Sunesis Pharmaceuticals is undergoing withering criticism Monday, after the firm tried to put a positive spin on the failure of its acute myeloid leukemia drug and both the press and Wall Street rejected its analysis with scorn instead.
Sunesis lost several major investors in October, when its drug vosaroxin combined with the chemotherapy cytarabine demonstrated median survival rates that were not statistically different than a placebo in its 711 patient, Phase III VALOR trial. But Sunesis tried to put some positive spin on those results Sunday, when it told a group of reporters at the American Society of Hematology that that “certain subsets” of patients in the Valor trial did see some survival benefit.
That amounts to what well-read biotech columnist Adam Feurstein at The Street called “a miraculous transformation during a Sunday morning press briefing” and is being greeted with wide suspicion across the industry.
“This type of post-study subgroup analysis sometimes raises eyebrows—especially when the original endpoints weren’t met,” wrote Alex Lash, Xconomy's national biotech editor, in a column Monday. But he said that Farhad Ravandi, a principal investigator in the trial and a leukemia specialist at MD Anderson Cancer Center in Houston, had assured Xconomy that the data could be read differently.
“Ravandi pointed out that people over 60—two-thirds of the 711 patients enrolled in VALOR—saw a 30 percent difference in survival rates between the vosaroxin and the placebo group, a statistically significant figure,” said Lash.
Whether or not investors or colleagues will accept that analysis remains to be seen, but one thing is certain: The sector is badly in need of a drug that is effective for the notoriously hard to treat AML, which hasn’t seen a drug approval in more than 40 years.
“We indeed regularly administer the same chemotherapy regimens that became standard care for AML in the 1970s, back when each of us was playing Little League baseball,” wrote two oncology specialists in a paper for the Journal of Clinical Oncology in 2012.
Because AML doesn’t necessarily metastasize, it has asurvival or cure rate or about 40 percent, with younger patients more likely to survive the chemotherapy and potential bone-marrow transplants used to treat the disease. But if there is a relapse, the prognosis for those over 60 is grim.
“That’s typically the group likely to do worse at the time of relapse. It’s difficult to improve their outcomes,” said Ravandi. “In VALOR, the subgroup over 60 had a clear benefit.”