Johnson & Johnson's prostate cancer drug shrinks tumors in early-stage trial

Johnson & Johnson on Saturday said its experimental once-daily oral prostate cancer drug caused tumors to disappear or shrink in an early-stage trial. J&J had gained access to the drug through its $3.05 billion deal to buy Halda Therapeutics last year.

The company was testing JNJ-6143 in patients with advanced prostate cancer who had received multiple treatments. Its novel approach selectively kills cancer cells by interfering with a protein they need to survive. In the trial, 77% of 31 evaluable patients receiving the 50-milligram dose saw their PSA levels, a blood marker used to monitor prostate cancer, fall by at least 50%; in 48% of patients, PSA levels fell by at least 90%. Among patients whose tumors could be measured using imaging, 69% had a confirmed complete or partial response.

"It adds a new mechanism of action to J&J's prostate cancer portfolio," a Johnson & Johnson spokesperson said. Common side effects were nausea and elevated cholesterol and triglyceride levels. One patient discontinued treatment due to adverse effects. The data were presented at the European Society for Medical Oncology Congress.