ADT-AAP combo effective for mHNPC independent of risk stratification

The combination of androgen deprivation therapy (ADT) with abiraterone acetate and prednisolone (AAP) treatment is effective against metastatic hormone-naïve prostate cancer (mHNPC) regardless of risk stratification, a recent study has shown.

Researchers performed a posthoc subgroup analysis of the STAMPEDE trial, including 901 participants, of whom 428 were defined as low-risk, while the remaining 473 were high-risk. The primary outcome was overall survival (OS), while secondary outcome was failure-free survival (FFS).

In the low-risk criteria, 220 received ADT alone, while 208 were treated with both ADT and AAP. In the high-risk group, 232 received monotreatment while 241 received the combination therapy.

A total of 330 deaths were reported. Absolute 3-year survival rates were significantly better in low-risk patients given the combination therapy (83 percent vs 78 percent; hazard ratio [HR], 0.66, 95 percent confidence intervals [CI], 0.44–0.98). The same was true for the high-risk group (65 percent vs 45 percent; HR, 0.54, 95 percent CI, 0.41–0.70).

Similar effects were reported for the secondary outcomes. In low-risk patients, 3-year FFS showed a 44-percent absolute improvement after ADT+AAP relative to ADT alone (76 percent vs 32 percent; HR, 0.25, 95 percent CI, 0.17–0.33). The magnitude of difference decreased in high-risk patients, but nevertheless remained significant (45 percent vs 12 percent; HR, 0.31, 95 percent CI, 0.25–0.39).

The present findings support the use of ADT and AAP for mHNPC independent of risk stratification, said the researchers.