Enzalutamide (Xtandi™) reduces the risk of skeletal-related events compared with placebo, as well as reducing pain and increasing quality of life in men with metastatic castration-resistant prostate cancer (mCRPC) according to new results from the AFFIRM study published in Lancet Oncology.

Bone is the most common site of spread in prostate cancer, accounting for about 90% of metastases, resulting in some of the most painful and functionally compromising complications of the disease.

Professor Johann De Bono, Professor of Experimental Cancer Medicine at The Institute of Cancer Research London, and Head of the Drug Development Unit at The Royal Marsden NHS Foundation Trust, comments:  “These quality of life data endorse the fact that enzalutamide is a major advance in the treatment of prostate cancer.”

Enzalutamide is a novel, once-daily, oral androgen receptor signalling inhibitor for the treatment of men with mCRPC whose disease has progressed on or after docetaxel therapy.

Prospective analyses of secondary endpoints in the Phase III AFFIRM trial examined first skeletal-related events and investigated several measures of pain control and patient-reported health related quality of life (HRQoL).

Researchers found that:

• Enzalutamide reduced the risk of skeletal-related events (such as radiation treatment to the bone and spinal cord compression) by 31% versus placebo (p=0.0001). The time to first skeletal-related event was significantly longer for patients on enzalutamide compared to placebo (16·7 months vs. 13·3 months; hazard ratio 0·69; p=0·0001).
• Enzalutamide significantly improved both pain severity and interference from baseline to week 13 compared with placebo (p<0·0001), as well as reducing the risk of pain progression (p=0.0018).
• Compared to the placebo group, a significantly higher percentage of patients on enzalutamide reported improvements in quality of life measured by FACT-P, a questionnaire used in prostate cancer studies which includes physical, emotional and functional wellbeing. Patients in the enzalutamide group had a significantly longer time to HRQoL deterioration than those in the placebo group (9·0 months vs. 3·7 months; HR 0·45; p<0·0001).

Prostate cancer is the most common cancer in men in Europe, accounting for over 20% of all cancer diagnoses (excluding non-melanoma skin cancer) and is the third most common cause of cancer death in Europe.

Up to 40% of men with prostate cancer develop metastatic disease and a high number of these men eventually fail androgen deprivation treatment, which is called castration-resistant prostate cancer (CRPC).

References

Fizazi K, Scher HI, Miller K et al. Effect of enzalutamide on time to first skeletal-related event, pain, and quality of life in men with castration-resistant prostate cancer: results from the randomised, phase 3 AFFIRM trial. Lancet Oncology, Volume 15, Issue 10. Pages 1147-1156, September 2014. 

Source: Lancet Oncology