J&J touts promising RIPTAC data with 59% PSA reductions in prostate cancer trial

At the European Society for Medical Oncology (ESMO) 2026 meeting in Madrid, Johnson & Johnson presented early clinical data from its RIPTAC platform, which the company acquired through a $3 billion purchase of Halda Therapeutics.

The data focus on HLD-0915, an oral small-molecule that simultaneously binds the androgen receptor and BRD4 to trigger tumor cell death. In a phase‑1 cohort of 22 patients with metastatic prostate cancer who had progressed on prior therapy, 59% achieved a PSA decline of more than 50% after at least two treatment cycles.

J&J executives described the results as the "best data we've ever seen" for a prostate‑cancer candidate, suggesting the "hold and kill" mechanism may overcome resistance pathways that limit many next‑generation oncology drugs.

The company plans to continue enrolling patients and will present additional data later, positioning the RIPTAC approach as a potential pillar of its oncology pipeline.