After disappointing efficacy data and a patient death, Oncternal Therapeutics is discontinuing two trials and looking for strategic alternatives.
The San Diego company said it would end a Phase 1 trial investigating ONCT-534, a dual-action androgen receptor inhibitor, in patients with metastatic castration-resistant prostate cancer. In the early-stage study, the drug did not show clinically meaningful improvements in disease like prostate-specific antigen levels, the company said Thursday.
Its other candidate, the ROR1-targeting autologous CAR-T dubbed ONCT-808, showed anti-tumor activity at all doses in aggressive B cell lymphoma. That included a complete metabolic response lasting eight months and long-term persistence of the CAR-T cells. While the asset also came with “expected treatment-emergent adverse events” for a CAR-T therapy, a patient died from “complications of shock” at the highest dose.
Based on these results, the company said it would stop development, cut its workforce and look for other options, including asset sales, licensing or a merger or acquisition.
James Breitmeyer“In light of these data and the challenging financing environment, we intend to explore strategic options with the hope of advancing and realizing value from our pipeline including ONCT-534, ONCT-808, zilovertamab and ONCT-216,” president and CEO James Breitmeyer said in a statement.
Oncternal’s stock $ONCT dipped nearly 3% on Friday morning, trading at $1.65.
Zilovertamab is a monoclonal antibody designed to inhibit the function of ROR1. It is in separate investigator-led studies in metastatic castration-resistant prostate cancer and chronic lymphocytic leukemia.
ONCT-216 is currently not listed in the company’s R&D pipeline. In April 2022, it discontinued recruiting subjects in a Phase 1/2 trial in Ewing sarcoma to “reallocate resources.”