The KEYNOTE-057 study Cohort B was a Phase II study of pembrolizumab monotherapy in patients with the BCG-unresponsive, high-risk non-muscle invasive disease, whose disease was characterized by a papillary tumor, pTa or T1, without CIS component.
The results from Cohort A of the same study, including a CIS component, resulted in a CR rate of 40% at 3 months and resulted in the approval by the US FDA of pembrolizumab as monotherapy in this patient population...
The KEYNOTE-057 study Cohort B was a Phase II study of pembrolizumab monotherapy in patients with the BCG-unresponsive, high-risk non-muscle invasive disease, whose disease was characterized by a papillary tumor, pTa or T1, without CIS component.
The results from Cohort A of the same study, including a CIS component, resulted in a CR rate of 40% at 3 months and resulted in the approval by the US FDA of pembrolizumab as monotherapy in this patient population.
We now focused on the Cohort B, so the patients without any carcinoma in situ component, which is a very, very unmet medical need perceived by the community, because for this patient, there is actually no standard of care established in the literature and established by the community. The study provided the same treatment paradigm of pembro monotherapy every 3 weeks for up to 2 years in case of no disease recurrence or progression.
The primary endpoint was a 12-month disease-free survival rate for high-risk disease recurrence, and provided a rate of 43% at 1 year, which was compelling. Also, when considering the fact that there were no new safety signals in this cohort, the safety data actually recapitulate that the data that had been already gathered in various disease settings with pembro monotherapy, including the Cohort A of the same study. Also, the quality of life parameters and the quality of life’s course revealed a stability or an improvement over time in patients who continued pembrolizumab without any recurrence.
So, overall, the study may justify a potential newer indication or expanded indication of pembrolizumab beyond the CIS component constraints.