Deciphera Soars on Positive Late-Stage Data in Gastrointestinal Stromal Tumors
Shares of Waltham, Mass.-based Deciphera Pharmaceuticals have soared more than 120% this morning after the company announced late-stage study data showed its asset ripretinib significantly improved progression-free survival in patients with fourth-line and fourth-line plus gastrointestinal stromal tumors.
Deciphera’s stock jumped from Monday’s close of $19.95 to $44.40 this morning after the company showed ripretinib provided 6.3 months of progression-free survival compared to one month from placebo. Ripretinib improved PFS in those patients by 85%, the company noted. Deciphera said it plans to file a New Drug Application with the U.S. Food and Drug Administration in the first quarter of 2020 for treatment of patients with advanced gastrointestinal stromal tumors (GIST) who have received prior treatment with imatinib, sunitinib and regorafenib. Ripretinib is a broad-spectrum KIT and PDGFRα (platelet-derived growth factor receptor α) inhibitor. Mutations in KIT and PDGFRα are known drivers of GIST, a cancer affecting the digestive tract or nearby structures within the abdomen, including the stomach or small intestine. Mutations in KIT kinase represent 75% to 80% of GIST cases, while mutations in PDGFRα kinase represent approximately 5% to 10% of cases. In June, the U.S. Food and Drug Administration granted Fast Track Designation to ripretinib for this designation.
Steve Hoerter, Deciphera’s new president and chief executive officer, called the results of the Phase III trial a “significant milestone” in the company’s mission to deliver new treatments for cancer.
“The data from INVICTUS reinforce our belief that ripretinib has the potential to transform the treatment of GIST, and our focus now turns to working closely with the FDA as they evaluate ripretinib for those patients with GIST who, having failed all currently approved therapies, are in desperate need of a treatment option,” Hoerter said in a statement.
Deciphera said the Phase III INVICTUS study included 129 patients with advanced GIST whose previous therapies have included at least imatinib, sunitinib, and regorafenib. The late-stage study significantly reduced the risk of disease progression or death by 85%, the company said. Ripretinib also showed a clinically meaningful improvement over placebo in terms of the secondary endpoint overall survival (OS). The drug provided a median OS of 15.1 months compared to 6.6 months for placebo.
There was some disappointment in secondary endpoints. Ripretinib demonstrated an objective response rate of 9.4% compared with 0% for placebo, but that was not statistically significant, the company said.
Ripretinib was generally well tolerated and consistent with data from previous studies.
In addition to the positive Phase III data, Deciphera also announced updated data from its ongoing Phase I clinical study of ripretinib in GIST. The data, which will be presented at an upcoming conference, will be submitted to the FDA to support the NDA for ripretinib in GIST, the company said. Hoerter said the additional six months of maturity “continue to support ripretinib’s potential across the broad range of KIT and PDGFRα mutations known to occur in patients with GIST following therapy with imatinib.”