There are a number of combination strategies with immune checkpoint blockade in urothelial cancer that are showing promise. Probably the furthest along is the combinations involving PD-1 or PD-L1 blockade, plus CTLA-4 blockade. We know from the DANUBE study that the combination of durvalumab plus tremelimumab did not show a survival benefit compared to standard of care platinum-based chemotherapy for the first-line treatment of patients with metastatic urothelial cancer, as determined in the primary study analysis...
There are a number of combination strategies with immune checkpoint blockade in urothelial cancer that are showing promise. Probably the furthest along is the combinations involving PD-1 or PD-L1 blockade, plus CTLA-4 blockade. We know from the DANUBE study that the combination of durvalumab plus tremelimumab did not show a survival benefit compared to standard of care platinum-based chemotherapy for the first-line treatment of patients with metastatic urothelial cancer, as determined in the primary study analysis. However, in the secondary analysis, limiting the comparison to patients with high PD-L1 expressing tumors, there actually was a benefit suggested. So, that combination certainly is of interest and the combination of CTLA-4 blockade plus PD-1 blockade that is ipilimumab plus nivolumab is being studied in the CheckMate 901 study which we should have results for hopefully in the not too distant future to define whether or not there’s a role for such combinations.
Other combination showing lots of promise in smaller studies include combinations with antibody-drug conjugates, plus immune checkpoint blockade. We know that the combination of pembrolizumab plus enfortumab vedotin results in a very high level of clinical activity in the frontline treatment of patients with metastatic urothelial cancer in a smallish cohort of cisplatin ineligible patients and that regimen has been moved forward to a number of Phase III studies.
More recently we’ve seen combinations with anti-HER2 antibody-drug conjugates with immune checkpoint blockade, also showing lots of promise raising the concept of whether or not there’s something special about antibody-drug conjugates in terms of their immunomodulatory activity. And then finally, combinations with multi-targeted kinase inhibitors. We’re seeing activity with combinations with sitravatinib, lenvatinib, cabozantinib with PD-1 or PD-L1 blockade. The mechanism of action of the multi-targeted kinase inhibitors and how they’re conferring immunomodulatory activity isn’t entirely clear, but potentially acting by inhibiting or repolarizing suppressive myeloid cells. So, promise for those combinations and those are being advanced to larger studies as well.