We conducted a study to assess how a combination of fuzuloparib, a PARP inhibitor, and abiraterone, an androgen receptor inhibitor, can affect localized high-risk prostate cancer. In this phase 2 trial involving 35 treatment-naive men, participants received six cycles of the therapy followed by radical prostatectomy.
We aimed to measure the effectiveness of this combination therapy by evaluating two main outcomes: pathological complete response (pCR) and minimal residual disease (MRD). The results were promising, showing a combined pCR/MRD rate of 46%, indicating that nearly half of the patients had no detectable disease after treatment. Additionally, 53% of participants remained free of biochemical progression two years post-treatment.
Interestingly, we found that specific molecular alterations, particularly involving biallelic homologous recombination repair and BRCA2 genes, were tied to quicker declines in prostate-specific antigen levels, which is a key marker for prostate cancer. Genomic analyses done after treatment revealed a reduction in MYC amplification and growth markers, suggesting that the therapy effectively targeted aggressive cancer attributes.
However, it’s important to note that about 23% of patients encountered grade ≥3 adverse events, highlighting some risks associated with this treatment. Overall, this study demonstrated the potential of combining these therapies in treating prostate cancer while establishing a foundation for exploring various biomarkers that could inform future research.