On December 12, 2025, the Food and Drug Administration approved niraparib and abiraterone acetate with prednisone for adults with deleterious or suspected deleterious BRCA2-mutated (BRCA2m) metastatic castration-sensitive prostate cancer (mCSPC), as determined by an FDA-approved test.

Full prescribing information for niraparib and abiraterone acetate with prednisone will be posted on Drugs@FDA.

Efficacy and Safety

Efficacy was evaluated in AMPLITUDE (NCT04497844), a randomized, double-blind trial in 696 patients with homologous recombination repair (HRR) gene-mutated (HRRm) mCSPC. Patients were randomized (1:1) to receive niraparib and abiraterone acetate plus prednisone (AAP) or placebo and AAP. All patients also received continued androgen deprivation therapy.

The major efficacy outcome measure was investigator-assessed radiographic progression-free survival (rPFS). Overall survival (OS) was an additional efficacy outcome. 

The trial demonstrated a statistically significant improvement in rPFS for niraparib and AAP compared to placebo and AAP in the overall population of patients with HRRm. In an exploratory analysis of 323 patients with BRCA2m, the hazard ratio (HR) for rPFS was 0.46 (95% CI: 0.32, 0.66) with median rPFS not estimable [NE] (95% CI: 41, NE) for niraparib and AAP and 26 months (95% CI: 18, 28) for placebo and AAP. In an exploratory analysis in 373 patients with non-BRCA2m, the HR for rPFS was 0.88 (95% CI: 0.63, 1.24), indicating that the overall improvement was primarily attributed to the results seen in patients with BRCA2m.

At the first interim analysis for OS, 91 deaths had occurred in the BRCA2m population, including 36 (22%) on the niraparib and AAP arm and 55 (34%) on the placebo and AAP arm.

The prescribing information includes warnings and precautions for myelodysplastic syndrome/acute myeloid leukaemia; myelosuppression; hypokalemia; fluid retention, and cardiovascular adverse reactions; hepatoxicity; adrenocortical insufficiency; hypoglycemia; increased fractures and mortality in combination with radium Ra 223 dichloride; posterior reversible encephalopathy syndrome; and embryo-fetal toxicity.

The recommended dose is 200 mg niraparib and 1,000 mg abiraterone acetate orally once daily in combination with 5 mg prednisone once daily until disease progression or unacceptable toxicity. Patients should also receive a gonadotropin-releasing hormone (GnRH) analog concurrently or should have had bilateral orchiectomy. 

Source: FDA