Zentalis Pharmaceuticals has announced a clinical collaboration agreement to evaluate the combination of its ZN-c3 and GlaxoSmithKline’s (GSK) ZEJULA (niraparib) in advanced epithelial ovarian cancer patients.

ZEJULA is an FDA and EMA-approved oral, once-daily poly (ADP-ribose) polymerase (PARP) inhibitor.

At present, Zentalis is conducting clinical studies with its oral WEE1 inhibitor product candidate, ZN-c3, as a monotherapy and in combination with certain standard of care therapies.

Zentalis Pharmaceuticals chairman and CEO Dr Anthony Sun said: “This clinical collaboration and supply agreement with GSK allows us to investigate the broader potential of our WEE1 inhibitor when used as part of a combination treatment with niraparib, a PARP inhibitor.

“As demonstrated in our preclinical studies, ZN-c3 is designed to have significant advantages over other investigational WEE1 inhibitor therapies. We believe this combination has the potential to meaningfully improve the outcomes for patients with ovarian cancer.”

Under the non-exclusive collaboration terms, Zentalis will perform the study with GSK providing all required doses of niraparib. Complete ownership of ZN-c3 would be maintained by Zentalis.

WEE1 plays a key role in cellular regulation and repair and its inhibition causes dysregulation of DNA replication and subsequently induces apoptosis.

Based on these complementary mechanisms of action, the use of WEE1 and PARP inhibitors is expected to potentially have synergistic anti-tumour activity.

Zentalis is currently conducting a Phase I/II clinical trial of ZN-c3 in patients with advanced solid tumours and a Phase Ib trial evaluating ZN-c3 in combination with chemotherapy in advanced ovarian cancer patients.

The company also plans to initiate a Phase I/II trial in combination with GSK’s niraparib for advanced ovarian cancer patients.