Zai Lab Starts Phase 3 Trial of ZL-2306 as First-Line Maintenance Therapy for Ovarian Cancer

Zai Lab Starts Phase 3 Trial of ZL-2306 as First-Line Maintenance Therapy for Ovarian Cancer

A Phase 3 clinical trial testing the investigational medication ZL-2306 (niraparib) as a maintenance therapy for ovarian cancer patients who are responding to their first-line chemotherapy has dosed its first participant, Zai Lab announced.

Niraparib is already available in the U.S. and EU under the brand name Zejula (by Tesaro) for the maintenance of ovarian cancer patients who have had a complete or partial response to platinum-based chemotherapy.

The approvals, however, are only for women who have received at least two prior chemotherapy regimens, and whose cancer returned after one of them.

ZL-2306 is an inhibitor of PARP proteins, which participate in DNA repair and other cellular mechanisms. Because certain tumors use PARP-mediated DNA repair for survival, PARP inhibition induces their death and makes them more sensitive to DNA-damaging agents.

The randomized, double-blind, placebo-controlled Phase 3 trial, to be conducted at multiple sites in China, will evaluate if once-daily ZL-2306 delays cancer progression or relapse in patients who are responding — either partially or completely — to first-line platinum-based chemotherapy.

Other PARP inhibitors have shown promise in this setting, when given to ovarian cancer patients with inherited mutations in their BRCA genes. But Zai Lab is testing ZL-2306 regardless of a patient’s BRCA mutation status.

“Zai Lab is making significant progress in its ZL-2306 clinical program, with the initiation of our second Phase 3 study in China as announced today,” Samantha Du, Zai Lab’s CEO, said in a press release. “We believe ZL-2306 offers substantial advantages over other treatment options for the Chinese market given its broad applicability across all patient population, regardless of gBRCA mutation status.”

Zai Lab recently completed a Phase 1 trial (NCT03551171) evaluating the safety, tolerability, and pharmacokinetics — referring to how a medicine is absorbed, distributed, metabolized, and excreted — of ZL-2306 in patients with ovarian cancer in China.

In September 2017, the company started a separate Phase 3 trial in China of ZL-2306 as a second-line maintenance treatment in patients with recurrent platinum-sensitive ovarian cancer.

Based on Zejula’s approval status in the U.S. and EU, Zai Lab filed a market registration application for ZL-2306 in Hong Kong, and estimates launching and marketing the medication there in the second half of 2018.

The China-based company is about to start a double-blind, multicenter Phase 3 trial (NCT03516084) of ZL-2306 in patients with extensive small cell lung cancer.

The company believes ZL-2306 may be a first-in-class Category 1 drug — which refers to innovative new medications — to treat multiple solid tumor types in China.