Zentalis Pharmaceuticals has reported positive data from a Phase Ib trial evaluating its WEE1 inhibitor, azenosertib combined with chemotherapy in patients with platinum-resistant ovarian cancer.
The trial enrolled a total of 115 patients across all chemotherapy combination groups.
Azenosertib was well tolerated in combination with multiple chemotherapy types and demonstrated significant clinical activity.
Improvements were observed in objective response rates (ORRs) and median progression-free survival (mPFS) in all patients.
Patients with Cyclin E1+ tumours, a subgroup having a poor prognosis and refractory to chemotherapy, benefited most in chemotherapy combination arms.
Azenosertib plus paclitaxel demonstrated the highest ORR of 50% followed by an ORR of 38.5% for azenosertib plus gemcitabine in all dosing schedules.
ORR of 35.7% was also observed when patients received azenosertib plus carboplatin and 19.4% in azenosertib plus PLD.
All azenosertib intermittent dosing groups showed Grade ≥3 treatment-related adverse events including neutropenia, fatigue, thrombocytopenia and anaemia.
Zentalis Pharmaceuticals CEO Kimberly Blackwell said: “We are very encouraged by our robust chemotherapy combination data, particularly the strong efficacy and tolerability results when dosing azenosertib intermittently.
“These data provide a compelling rationale to advance azenosertib into a registrational study in combination with either carboplatin or paclitaxel in Cyclin E1+ ovarian cancer.”
A recommended Phase II dose was also determined for each of the azenosertib combinations with carboplatin, paclitaxel, and PLD.
The company also plans to start a Phase III study comparing azenosertib dosed intermittently along with either paclitaxel or carboplatin in Cyclin E1+ platinum-sensitive ovarian cancer patients.
The study is anticipated to start in the first quarter of next year.