This study examined the benefit of adding apalutamide (JNJ 56021927) to standard hormone therapy in men with castration-resistant prostate cancer (CRPC). Researchers reported preliminary evidence for apalutamide as a safe and effective additional hormone therapy for high-risk CRPC.

Hormone therapy is the standard of care for advanced prostate cancer. It targets the production of male hormones (such as testosterone) and reduces their effect on cancer cell growth. Over time, many men stop responding to standard hormone therapy. This is called castration-resistant prostate cancer (CRPC).

In cases of CRPC, secondary hormone therapy is often added to standard hormone therapy for a more intensive intervention. Apalutamide has recently been under the focus of investigation as a new type of secondary hormone therapy. Early studies have reported good effectiveness, which could make it suitable for men at high risk of cancer progression or recurrence. 

The aim of this study was to examine apalutamide in the treatment of high-risk CRPC.

51 men with CRPC at high risk of cancer progression were included in this study. All men received treatment with apalutamide in addition to their ongoing standard hormone therapy. The men included did not have cancer spread to distant organs (metastatic disease) before the study. Treatment outcomes were followed for an average of 28 months.

After 12 weeks of treatments, 89% of men showed a treatment response (based on blood tests) of at least 50%. A response of at least 50% at some stage during treatment was observed in 94% of men. 

53% of men experienced cancer progression (based on blood tests) during the study follow-up. The average time until cancer progressed was 24 months. Approximately 75% of men remained free of metastatic disease at 24 months.

Fatigue was the most common side effect (reported in 61% of men). Severe fatigue was reported in 4% of men. 43% of men experienced diarrhea and 39% of men experienced nausea. Overall, 18% of men discontinued treatment due to side effects.

Researchers concluded that apalutamide was safe and effective in the treatment of high-risk CRPC when added to standard hormone therapy.

Randomized trials comparing apalutamide to placebo (a control substance with no active effect) or to other treatments are needed to confirm these preliminary results.