Zentalis Pharmaceuticals (ZNTL) 7th Annual Oncology Innovation Summit: Insights for ASCO & EHA summary

Key clinical updates

• Phase I-B MUIR study of azenosertib plus paclitaxel in platinum-resistant ovarian cancer showed a manageable safety profile and efficacy exceeding historical paclitaxel data, with optimal dosing identified as 250 mg once daily, five days on, two days off.

• The combination's benefit supports broader application in earlier ovarian cancer lines and other tumor types where taxanes are standard, such as breast and other solid tumors.

• DENALI Part 2 is enrolling, aiming for accelerated approval, with 400 mg five days on, two days off selected as the optimal monotherapy dose based on superior efficacy and comparable safety to 300 mg.

• Part 2C was added to include patients previously treated with taxane regimens, strengthening the dataset for evolving treatment landscapes.

• The pivotal DENALI Part 2 readout is expected by year-end, focusing on overall response rate (ORR) as the primary endpoint.

Efficacy and safety expectations

• A response rate of 30% ±5% and duration of response between five and six months are considered meaningful for regulatory approval and clinical uptake.

• Safety improvements have been observed, with lower discontinuation and cytopenia rates compared to chemotherapy and ADCs.

• The agent does not cause neuropathy, eye toxicity, ILD, or hair loss, differentiating it from other therapies.

• Most gastrointestinal and fatigue-related adverse events are low-grade and manageable.

Strategic positioning and future directions

• Azenosertib is positioned as an oral, non-chemotherapeutic, biomarker-directed therapy for Cyclin E1 high patients, with potential for sequencing after ADCs or in combination regimens.

• Preclinical and clinical data suggest activity in ADC-resistant models and potential benefit in triple-negative breast cancer.

• The evolving landscape may see azenosertib used both as monotherapy and in combination, in ovarian and other solid tumors.