CG Oncology's Bladder Cancer Therapy Impresses at AACR

California-based CG Oncology, a clinical-stage pharmaceutical company that primarily develops immunotherapies for cancer, presented positive interim Phase II results from its Core1 trial studying the use of CG0070 at the American Association for Cancer Research (AACR) Annual Meeting. As the company’s most promising biologic candidate, CG0070 is designed to treat patients diagnosed with non-muscle-invasive bladder cancer (NMIBC) that do not respond to bacillus-calmette-guerin (BCG).

Bladder cancer is diagnosed at a rate of 19.7 in 100,000 people per year, according to the National Cancer Institute (NCI), with NMIBC specific diagnosis in the majority of these cases. Typically, BCG is the standard of care for NMIBC patients and is seen to be effective in a majority of cases. The small subset of patients that do not respond to BCG treatment are left with unmet medical needs, which is where CG0070 comes in.

The Phase II Core1 study (NCT04387461) is evaluating the efficacy of CG0070 when given in combination with Merck’s Keytruda (pembrolizumab). Efficacy was demonstrated at the interim three-month mark, as 89% of patients displayed a complete response. The response was measured again at six months, nine months and one year, reinforcing efficacy data with respective 85%, 78% and 75% complete response rates.

Core1 included 18 patients at the interim data cutoff point on Apr. 7, 2022, but the target enrollment number is 37. To be included, patients must have recurrent NMIBC and have gone through BCG immunotherapy at least one year prior.

Dr. Edward Uchio, M.D., a urologic oncologist at UCI Medical Center, commented on the results. “These interim results continue to be potentially game-changing in patients who are often reluctant to undergo radical surgery for non-invasive bladder cancer. CG0070, which has been administered in over 150 patients to date, exhibits a dual mechanism of action shown to be highly clinically meaningful in bladder cancer,” Uchio said. 

The open-label study has an estimated completion date of June 2023, with a primary endpoint measuring complete response rates in participants. Secondary endpoints include adverse events in response to the dual treatment, median duration of response, median overall survival and median progression-free survival.

The Phase III Bond-003 study (NCT04452591) for CG0070 is currently recruiting to achieve the target of 110 participants, which would encompass a larger population, generating a more comprehensive data set. The Bond-003 study differs from the Core1 by evaluating CG0070 as a monotherapy, rather than in combination. The primary endpoint for this open-label study is whether a patient demonstrates a complete response to the therapeutic. Secondary endpoints will measure time to tumor progression, adverse events in response to CG0070 monotherapy, median progression-free survival and median duration of response.

CG has the intent to evaluate CG0070 in combination with chemotherapy nivolumab with an indication to treat bladder cancer, in addition to other forms of solid tumor cancers. Beyond these studies, there is an opportunity to evaluate CG0070 in combination with various checkpoint inhibitors.