FDA Halts Phase 1/2 CAR T-Cell Study in Pancreatic and Prostate Cancer

The phase 1/2 study of the investigational chimeric antigen receptor (CAR) T-cell agent BPX-601 administered as treatment of patients with previously treated metastatic pancreatic or prostate cancer is no longer active after the FDA place a partial clinical hold on the trial, announced Bellicum Pharmaceuticals, Inc, in a press release.

Death of a patient with pancreatic cancer was the cause of the partial hold. The FDA has requested that the company investigate the death and provide answers to their question despite the clinical investigator and the company having reported that the patient’s death was unrelated to treatment with BPX-601.

Prior to the halt, the dose-escalation trial was assessing the feasibility, safety, and activity of BPX-601 in patients with previously treated advanced solid tumors. Patients enrolled were diagnosed with either metastatic pancreatic cancer with tumor progression after 1 prior standard chemotherapy, metastatic gastric or gastroesophageal junction cancer with tumor progression after one prior standard chemotherapy, or hormone-refractory prostate cancer with tumor progression after treatment with a taxane-containing regimen and at least one androgen synthesis inhibitor. The co-primary end points of the study are safety and objective response rate. Safety in this study is determined by dose-limiting toxicity, treatment-emergent adverse events (TEAEs), serious TEAEs, and pharmacodynamics.

To be eligible to enroll, patients were required to a tumor with positive prostate stem cell antigen expression as determined by central testing and radiographically measurable disease. The minimum age of patients eligible for the study was 18 years, and patients were required to have a life expectancy more than 12 weeks with an ECOG performance status of 0 or 1. Adequate venous access and organ and blood cell count were also requisites for inclusion in the study.

In the phase 1 dose-escalation portion of the study, patients were given an intravenous (IV) infusion of BPX-601 followed by at least 1 IV infusions of rimiducid. Escalation of BPX-601 doses continues in the study until the recommended cell dose level is reached. In the phase 2 dose-expansion portion of the study, IV infusions of BPX-601 are administered at the recommended cell dose level and followed by a minimum of 1 IV infusions of rimiducid.

The mechanism of action of BPX-601 is T cell proliferation and persistence, and production of immunomodulatory cytokines. The drug enables the CAR-T to cancel key immune inhibitory mechanisms.

_Reference:

_{Bellicum reports clinical hold placed on BPX-601 phase 1/2 clinical trial. News release. Bellicum Pharmaceuticals, Inc. December 7, 2020. Accessed December 8, 2020.https://yhoo.it/3oyFpm1}