The U.S. Food and Drug Administration (FDA) will review an application requesting duvelisib’s full approval for the treatment of relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and accelerated approval for relapsed/refractory follicular lymphoma (FL).
The new drug application, submitted by Verastem, was granted priority status, which shortens the review time from 10 to six months. A decision now is expected by Oct. 5.
Duvelisib is a first-in-class inhibitor of phosphoinositide 3-kinase-delta and (PI3K-delta) and PI3K-gamma. PI3K signaling may lead to the proliferation of malignant B- and T-cells and is thought to play a role in the formation and maintenance of the supportive tumor microenvironment.
The new drug application is based on two studies: the Phase 2 DYNAMO study (NCT01882803) in indolent non-Hodgkin lymphoma (iNHL), and the Phase 3 DUE clinical trial (NCT02004522) in patients with CLL/SLL.
Indolent non-Hodgkin’s lymphoma covers a range of lymphoma subtypes, but all progress slowly, which can make treatment difficult. The DYNAMO study was designed to evaluate the safety of duvelisib as a monotherapy in subjects with iNHL among patients who did not respond to Rituxan (rituximab).
Verastem reported a 43 percent overall response rate in patients with FL and a 68 percent response rate in those with SLL. Only 33 percent of patients with marginal zone lymphoma responded to the treatment. Nonetheless, the study met the primary goal of overall response rate.
The DUO study was designed to examine the effectiveness of duvelisib as monotherapy versus Arzerra (ofatumumab) monotherapy in subjects with relapsed or refractory CLL/SLL. In this study, duvelisib was seen to outperform Arzerra in patients with relapsed/refractory CLL/SLL.
The oral therapy nearly halved the risk of disease progression or death, and held patients progression-free for a median of 13.3 months — about 3.4 months longer than in patients treated with Arzerra — and also met the study’s primary goal.
“Obtaining Priority Review in the U.S. for duvelisib marks another important milestone for Verastem and speaks to the unmet need in relapsed/refractory CLL/SLL and FL and the urgency to identify effective therapies to treat these patients,” Robert Forrester, president and CEO of Verastem, said in a press release.
“As an orally administered therapy, we believe duvelisib will provide an important treatment option for patients with CLL/SLL and FL, and for the physicians who treat them. We look forward to working with the FDA during the review process,” Forrester said. “We are continuing our commercial preparations for duvelisib to execute the launch promptly in the U.S. if approved. In parallel, we are exploring ex-U.S. partnering opportunities for duvelisib and plan to file a European Marketing Application towards the end of the year.”