CG Oncology, Inc. announced that data from the Phase 3 BOND-003 study evaluating the efficacy and safety of cretostimogene monotherapy in patients with high-risk Non-Muscle Invasive Bladder Cancer (NMIBC) unresponsive to Bacillus Calmette Guerin (BCG), showed that 75.2% of patients (79 out of 105 [95% confidence interval (CI), 65-83]) achieved a complete response (CR) at any time, as of the cutoff date of April 1, 2024. In addition, cretostimogene has shown durable responses over time with twenty-nine patients maintaining a complete response for 12 months or more, pending evaluation and assessment of ongoing responses in twenty-two patients as of the data cutoff. Median duration of response (DOR) was not reached.

92.4% cystectomy-free survival was observed and none of the patients with a complete response had undergone radical cystectomy or showed nodal or metastatic progression. Cretostimogene is an investigational oncolytic immunotherapy which has shown selective oncolysis and potent anti-tumor immune response, and is being evaluated in BOND-003 (NCT04452591), a single-arm, Phase 3, monotherapy clinical trial for the treatment of patients with high-risk BCG-unresponsive NMIBC with carcinoma in-situ (CIS) with or without Ta or T1 papillary tumors. The fully enrolled global trial with a total of 112 patients is currently ongoing in North America and the Asia-Pacific region.

The primary endpoint of the study is CR at any time, with DOR measured as a secondary endpoint. The highly pre-treated study population includes patients with prior intravesical chemotherapy and systemic immunotherapy. There were no Grade 3 or higher treatment-related adverse events (TRAEs) or deaths reported, and two patients (1.8%) had serious TRAEs (Grade 2).

No treatment-related discontinuation of cretostimogene was observed. 94.5% of patients completed all expected treatments. TRAEs occurred in 70 patients (62.5%).

The most common TRAEs (=10%) were bladder spasm, pollakiuria, dysuria, micturition urgency, and hematuria, as of the safety cutoff date of January 31, 2024. Last December, the U.S. Food and Drug Administration (FDA) granted both Fast Track Designation and Breakthrough Therapy Designation for cretostimogene in high-risk BCG-unresponsive NMIBC with carcinoma in-situ with or without Ta or T1 papillary tumors.