Zentalis Pharmaceuticals said on Tuesday, Sept. 8, 2026, that its compound azenosertib has a clearer path after the FDA lifted a clinical hold without requesting changes to the dose or schedule. The company said the decision was significant because the hold was lifted without further requests for changes. The company made the remarks at the Wells Fargo 21st Annual Healthcare Conference, where executives discussed trial timelines, safety data and the potential role of azenosertib in platinum-resistant ovarian cancer.
Zentalis shares were up 196% year to date and 145% over the past year, trading at $4.03 with a market capitalization of about $380 million. The company said its cash runway extends into the first half of 2028, after burning roughly $128 million in free cash flow over the last 12 months. Its current ratio was 4.82.
Executives said the DENALI Parts A and B trials were fully enrolled as of summer 2025. Top-line results from DENALI Part 2 are expected in the first half of 2027, while signals from the MIRROR (MUIR) trial are expected in 2026. The company previously presented data on paclitaxel combinations at ASCO earlier in 2025.
Azenosertib is being evaluated as a monotherapy at 400 milligrams daily on a five-days-on, two-days-off schedule, and at 250 milligrams in combination with paclitaxel. The company said the drug has been evaluated in about 1,000 patients across multiple trials. In DENALI Part 1b, grade 3 or higher neutropenia was reported in about 11% to 12% of patients, compared with 45% cited for some antibody-drug conjugates. The chief medical officer described the neutropenia rate as low double digits, with at least half of the cases at grade 3, and said high-grade neutropenia was a rare event. The company said the discussion covered both monotherapy and combination approaches.
The company said cyclin E1 high expression was present in about 50% of platinum-resistant ovarian cancer patients screened. Historical response rates in cyclin E1-high patients have been 30% or higher in MAMMOTH, DENALI Part 1b and dose-escalation data, compared with 4% to 13% for single-agent chemotherapy. The chief executive officer said a response rate of 30% or greater and a duration of response of five months or better would represent a meaningful win, adding that the larger the response number, the larger the win.
Zentalis also noted that folate receptor alpha overlap with platinum-resistant ovarian cancer is about 20%, and that single-agent weekly paclitaxel is used in about 10% to 15% of patients. The company said azenosertib could offer patients an opportunity to take a chemotherapy break.
The company's cohort 2C included about 40 patients. The transcript was moderated by Wells Fargo biotech analyst Eva Forte, with Zentalis executives participating.
