CG Oncology Presents Preliminary Phase 2 Data with CG0070 in Combination with KEYTRUDA® (pembrolizumab) in Non-Muscle-Invasive Bladder Cancer Unresponsive to Bacillus Calmette-Guerin

CG Oncology, Inc., a clinical-stage biotechnology company focused on developing oncolytic immunotherapies for patients with advanced cancer, today announced preliminary Phase 2 study (CORE1) results for CG0070 in combination with KEYTRUDA^® (pembrolizumab), for the treatment of patients with Non-Muscle-Invasive Bladder Cancer (NMIBC) unresponsive to Bacillus Calmette-Guerin (BCG).

The preliminary Phase 2 results showed that a combination of CG0070 and pembrolizumab was well tolerated with encouraging early efficacy data in 9 patients. The results (Abstract #955) were presented as a late-breaking oral presentation at The Society for Immunotherapy of Cancer (SITC) 2021 Annual Meeting.

"We are excited to announce these preliminary results toward CG0070's safety, tolerability and clinical efficacy in patients with bladder cancer unresponsive to BCG who have limited treatment options," said Arthur Kuan, Chief Executive Officer, CG Oncology. "We hope to see continued responses as the study progresses, as CG0070's dual mechanism of action has shown to be highly effective in this difficult-to-treat patient population."

Summary of Preliminary Clinical Results

• The analysis, based on a data cutoff on November 8, 2021, reported that 100% of patients evaluable for efficacy (n=9) have achieved complete response (CR) at the initial 3-month timepoint. Of those patients that have reached additional timepoints, 100% (n=6) have also maintained a CR through 6 months and 100% (n=3) at the 9-month assessment.
• Treatment related adverse events (AEs) were limited to transient grade 1-2 local genitourinary symptoms and immune-related adverse events including urinary frequency, bladder spasm, fatigue, chills, autoimmune thyroiditis, blood discharge, dysuria, and flu-like symptoms. No treatment-related grade 3 or higher AEs or severe adverse events (SAEs) have been observed.

"These preliminary results are exciting," said Dr. Roger Li, M.D., lead study investigator and Urologic Oncologist at Moffitt Cancer Center. "If similar trends hold moving forward, we may have a game changer to combat BCG-unresponsive bladder cancer for patients with significant unmet medical need."

About the CORE1 Study

Under a previously announced clinical collaboration with Merck (known as MSD outside the US and Canada) relating to the investigation of CG0070 used in combination with pembrolizumab, the goal of CORE1, which will enroll up to 35 patients, is to evaluate the safety and efficacy of CG0070 plus KEYTRUDA for the treatment of NMIBC unresponsive to BCG.

More information about the study can be found at www.clinicaltrials.gov (NCT04387461).

KEYTRUDA^® is a registered trademark of Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.

About CG0700

CG0070, a selective oncolytic immunotherapy based on a modified adenovirus type 5 backbone that contains a cancer-selective promoter and a GM-CSF transgene, destroys bladder tumor cells through their defective retinoblastoma (Rb) pathway. CG0070 was designed to replicate inside tumor cells with dysfunctional Rb pathways, causing tumor cell lysis and immunogenic cell death. The rupture of cancer cells releases tumor-derived antigens and GM-CSF, which stimulates a systemic anti-tumor immune response. In advanced clinical trials, CG0070 is a safe and efficacious agent in NMIBC following BCG failure. CG0070 is currently in late-stage clinical trials across a variety of solid cancers, as a monotherapy or in combination with immune checkpoint inhibitors.

About CG Oncology

CG Oncology is a clinical-stage biotechnology company focused on developing the next evolution of oncolytic immunotherapy for patients with advanced cancer. Our lead candidate, CG0070, is a selective oncolytic immunotherapy in a Phase 3 trial with CG0070 as a monotherapy for the treatment of BCG-unresponsive NMIBC, and a combination Phase 2 study of CG0070 with KEYTRUDA^® (pembrolizumab) in the same indication. Other types of bladder cancer are being evaluated with CG0070 in combination with OPDIVO® (nivolumab), and additional indications in other solid tumors are being pursued with CG0070 in combination with other immune checkpoint inhibitors. At CG Oncology, we aim to take the next evolutionary step in delivering innovative cancer care to millions of patients in need worldwide. Learn more at www.cgoncology.com.