Azenosertib

• Zentalis Pharmaceuticals is restructuring to prioritize the late-stage development of azenosertib, a WEE1 inhibitor, for gynecological malignancies. • The restructuring includes a workforce reduction of approximately 40% to extend the company's cash runway into late 2027. • Azenosertib has shown a 5.5-month median duration of response with no new safety signals in mid-trial data from the MAMMOTH and DENALI studies. • Zentalis plans to present updated clinical data and regulatory plans for azenosertib at a corporate event on January 29, 2025.

Zentalis Pharmaceuticals presented updated clinical data on azenosertib, highlighting its potential in treating Cyclin E1+ platinum-resistant ovarian cancer (PROC).

• The FDA has lifted the partial clinical hold on Zentalis Pharmaceuticals' azenosertib studies, allowing for the resumption of patient enrollment in ongoing trials. • The decision follows a comprehensive safety assessment review by the FDA, reinforcing confidence in azenosertib's therapeutic potential, especially for gynecologic malignancies. • Azenosertib, an orally bioavailable WEE1 inhibitor, is being evaluated as both a monotherapy and in combination to treat ovarian cancer and other tumor types. • Zentalis plans to present monotherapy data on azenosertib later in 2024, providing updates on clinical development timelines and data presentation.

• The FDA has lifted the partial clinical hold on trials evaluating azenosertib, a WEE1 inhibitor, in patients with advanced solid tumors, allowing studies to resume enrollment. • The hold was initiated in June 2024 due to two deaths from presumed sepsis in the DENALI trial, but the FDA has now reviewed and approved Zentalis Pharmaceuticals' response package. • Azenosertib is being investigated as a monotherapy and in combination for platinum-resistant ovarian cancer and uterine serous carcinoma, with additional data expected in Q4 2024.

• The FDA has lifted the partial clinical hold on Zentalis Pharmaceuticals' azenosertib studies, allowing the company to resume enrollment in ongoing clinical trials. • Zentalis plans to present azenosertib monotherapy data and provide updates on clinical development at a corporate event later this year. • The company remains confident in azenosertib's therapeutic potential for addressing unmet needs in gynecologic malignancies. • Zentalis is on track to meet all previously disclosed data guidance for 2024, including key clinical study results expected in Q4.