Tuesday, Zentalis Pharmaceuticals Inc ( ZNTL ) announced that the FDA has placed a partial clinical hold on the following studies of azenosertib:

Phase 1 ZN-c3-001 dose-escalation study in solid tumors.

Phase 2 ZN-c3-005 (DENALI) study in platinum-resistant ovarian cancer (PROC).

Phase 2 ZN-c3-004 (TETON) study in uterine serous carcinoma (USC).

This action follows two recent deaths due to presumed sepsis in the DENALI study.

“Over 500 patients have been treated with azenosertib monotherapy to date, and we believe that our data indicate a favorable therapeutic index that could potentially offer meaningful benefits. We have completed enrollment for Cohort 1b of the DENALI study, where we’ve enrolled more than a hundred patients, further demonstrating the support we’ve seen for having a novel oral therapy like azenosertib. We look forward to sharing these results along with overall efficacy and safety data from DENALI Cohort 1b later this year,” said Kimberly Blackwell, CEO of Zentalis.

In addition to sharing topline results of Cohort 1b of DENALI, the company remains on track to present results from the ZN-c3-001 and Phase 1/2 ZN-c3-006 (MAMMOTH) studies later this year.

The company will provide additional updates to the azenosertib clinical development and other data timelines following the resolution of the partial clinical hold.

Also Read: Zentalis Gears Up for Phase 3 Study of Azenosertib after Positive Phase 1b Outcomes.

Price Action: ZNTL shares are down 24.9% at $6.30 during the premarket session at last check Tuesday.