Zentalis Pharmaceuticals (ZNTL) Leerink Global Healthcare Conference 2025 summary

Vision and strategy overview

• Focused on advancing azenosertib for platinum-resistant ovarian cancer (PROC), especially cyclin E1 positive patients, with a clear regulatory and clinical development path.

• Market for ovarian cancer expected to double in three years, with significant unmet need for biomarker-selected therapies.

• Over 50% of PROC patients are cyclin E1 positive, a group with poorer prognosis and lower response to standard chemotherapy.

• Strategic alignment and organizational changes made to ensure cash runway into late 2027, supporting key clinical readouts.

• Pipeline focus is on Denali part two and a confirmatory phase three study, with top-line data expected by end of 2026.

Clinical data and biomarker strategy

• Azenosertib monotherapy shows >30% ORR in cyclin E1 positive PROC patients, with median duration of response of 5.5 months at 400mg dosing.

• Safety profile at 300mg and 400mg doses is manageable, with low rates of severe complications and better tolerability than other WEE1 inhibitors.

• Subgroup analysis shows consistent efficacy across patients with 1-3 and 4+ prior lines of therapy, with ORR of 40% and 25% respectively.

• IHC assay for cyclin E1 overexpression is a robust biomarker, capturing more patients than DNA amplification alone, and is ready for use in registration studies.

• Cyclin E1 status is stable across treatment lines, supporting use of archival tissue for patient selection.

Regulatory and trial design updates

• Denali part two uses a seamless design aligned with FDA for potential accelerated approval, with dose selection between 300 and 400 mg.

• Fewer prior lines of therapy (one to three) in part two, expected to improve response rates and patient tolerability.

• No required changes to dose or schedule after FDA review; future agency interactions planned for dose confirmation and phase three design.

• Confirmatory phase three trial to start after dose selection, enrolling similar patient population as Denali part two.

• Interim analyses and regulatory updates planned throughout 2024 and 2025.