30 November 2020 - - US-based biopharmaceutical company Deciphera Pharmaceuticals, Inc. (NASDAQ: DCPH) has completed its target enrollment in the INTRIGUE Phase 3 clinical study evaluating the efficacy and safety of Qinlock in patients with second-line gastrointestinal stromal tumor, the company said.

Qinlock, the company's switch-control tyrosine kinase inhibitor, is currently approved in the US, Canada, and Australia for patients with fourth-line GIST.

The INTRIGUE Phase 3 clinical study is a randomized, global, multicenter, open-label study to evaluate the efficacy and safety of Qinlock compared to sunitinib in patients with GIST previously treated with imatinib.

This study was designed to support regulatory approvals in second-line GIST patients in the United States, Europe, and other major markets. Approximately 426 patients were randomized 1: 1 to either Qinlock 150 mg once daily or sunitinib 50 mg once daily for four weeks followed by two weeks without sunitinib.

The primary efficacy endpoint is median progression-free survival as determined by independent radiologic review using modified Response Evaluation Criteria in Solid Tumors (RECIST).

Secondary endpoints as determined by independent radiologic review using modified RECIST include Objective Response Rate and Overall Survival.

The study is being conducted at 122 investigational sites in 22 countries.

Qinlock is a switch-control tyrosine kinase inhibitor that was engineered to broadly inhibit KIT and PDGFRA mutated kinases by using a dual mechanism of action that regulates the kinase switch pocket and activation loop.

Qinlock inhibits primary and secondary KIT mutations in exons 9, 11, 13, 14, 17, and 18 involved in GIST, as well as the primary exon 17 D816V mutation.

Qinlock also inhibits primary PDGFRA mutations in exons 12, 14, and 18, including the exon 18 D842V mutation, involved in a subset of GIST.

Qinlock is approved by the US FDA for the treatment of adult patients with advanced GIST who have received prior treatment with three or more kinase inhibitors, including imatinib.

It is also approved by Health Canada for the treatment of adult patients with advanced GIST who have received prior treatment with imatinib, sunitinib, and regorafenib and by the Australian Therapeutic.