Dr. Antonarakis on PD-1/PD-L1 Monotherapy in Prostate Cancer

Emmanuel S. Antonarakis, MBBCh, professor of oncology, Johns Hopkins Medicine, discusses the optimal use of PD-1/PD-L1 monotherapy in prostate cancer.

In a biomarker unselected population, any PD-1 or PD-L1 inhibitor by itself is probably not going to be enough, says Antonarakis. However, single agent use of these inhibitors might be beneficial in certain subsets of patients with the disease, such as those who have mismatch repair deficiency or microsatellite instability—high genotypes. PD-1/PD-L1 monotherapy may also show activity in patients with CDK12 mutations, adds Antonarakis; those with this mutation account for 6% to 7% of all prostate cancer cases. Additionally, some preliminary data that have not yet been confirmed suggest that patients with BRCA1/2 mutations may also be slightly enriched for a response to single-agent PD-1 inhibition, concludes Antonarakis.