Evaluating the effects of abiraterone acetate in combination with androgen deprivation therapy for the treatment of metastatic hormone-sensitive prostate cancer.

This study examined the effects of abiraterone acetate (AA; Zytiga) in combination with androgen deprivation therapy (ADT) for the treatment of metastatic hormone-sensitive prostate cancer (mHSPC). The data showed that AA and ADT combination improves the outcomes in these patients.

Patients with mHSPC have prostate cancer that has spread beyond the prostate gland and is responsive to hormonal therapy such as androgen deprivation therapy (ADT). ADT reduces the production of androgens (male sex hormones such as testosterone). Reducing these androgens prevents cancer cell growth.

AA is a medication that blocks the effect of male sex hormones. Therefore, it slows down prostate cancer growth. AA is usually given to patients when they are no longer sensitive to ADT (castrate-resistant). However, the effectiveness of AA in patients with mHSPC treated with ADT is not well known.

The authors reviewed 2 studies with a total of 2201 men with mHSPC. Patients were assigned to receive either AA 1000 mg daily and low-dose prednisone (5 mg; Deltasone) plus ADT or ADT alone.

Patients who received AA plus ADT were 36% more likely to survive compared to those who just received ADT. There was no significant difference in the quality of life across the 2 treatment groups.

The addition of AA to ADT also reduced the probability of death due to prostate cancer compared to ADT alone. Patients who received AA plus ADT were 42% less likely to die due to prostate cancer compared to those who received ADT alone. They were also 65% less likely to experience disease progression compared to those who received ADT alone. 

AA plus ADT increased the risk of moderate to severe side effects by 34% compared to ADT alone. Patients treated with AA plus ADT were 50% more likely to stop treatment due to side effects compared to ADT alone.

This study showed that adding AA to ADT in patients with mHSPC improved their outcomes and also increased the risk of side effects.