The Roger Li, MD discussed the updated results from the CORE1 trial, which explored the combination of Cretostimogene Grenadorepvec (CG0070), an oncolytic adenovirus, and Pembrolizumab in patients with BCG unresponsive carcinoma in situ (CIS) containing muscle-invasive bladder cancer (MIBC).
The study enrolled patients who had previously received an adequate amount of BCG treatment and had recurrent CIS-containing tumors. The standard treatment for such patients is radical cystectomy, but those who refused or were ineligible for the procedure were included. Exclusion criteria involved autoimmune disease, steroid use, and small bladder capacities.
The treatment regimen consisted of intravesical CG0070 induction therapy administered weekly for six weeks, followed by maintenance therapy at months 3, 6, 9, 12, and 18. Pembrolizumab was given intravenously every 6 weeks according to the standard dosing regimen.
The primary endpoint of the study was complete response at 12 months, assessed through cystoscopy, urine cytology, and bladder biopsies. Secondary endpoints included complete response at any time, progression-free survival, cystectomy-free survival, and safety.
Out of 35 enrolled patients, the majority had CIS, with an 85% complete response rate observed in the valuable patients who reached the 12-month mark. Around 68% of patients maintained their complete response at the assessed endpoints.
The safety profile of the combination therapy was similar to monotherapy trials of CG0070 or Pembrolizumab. Adverse events were primarily bladder-related symptoms and manageable immune-related side effects.
Based on the positive results, the Roger Li, MD expressed excitement about designing a phase 3 trial to further investigate the efficacy and adverse events profile of the combination therapy compared to Pembrolizumab monotherapy.
The Roger Li, MD, conveyed the message that the combination of CG0070 and Pembrolizumab demonstrated promising efficacy and supported the hypothesis of synergistic action between the oncolytic virus and immune checkpoint blockade. Further studies are planned to understand the underlying mechanisms and enhance immunotherapy for bladder cancer.
Roger Li, MD, is a genitourinary oncologist from Moffitt Cancer Center