SUZHOU, China, Feb. 27, 2026 /PRNewswire/ -- Intravesical BCG is the standard of care (SOC) for BCG-naïve high-risk non-muscle-invasive bladder cancer (NMIBC) patients. However, the scarcity of BCG products has become a global phenomenon, and coupled with the side effects of BCG therapy itself, means that a substantial number of patients cannot access effective BCG treatment. Therefore, it is essential to seek better alternative therapies to BCG in order to meet clinical needs. Based on this, ImmVira Group is further expanding the clinical trial of its core oncolytic virus product, MVR-T3011—originally targeting BCG-unresponsive high-risk bladder cancer—to further include BCG-naïve bladder cancer patients.

On February 26, 2026, at the ASCO GU 2026 Conference in San Francisco, California, ImmVira Group announced preliminary positive results from its clinical trial evaluating MVR-T3011, an oncolytic virus, in BCG-naïve high-risk papillary Ta/T1 NMIBC patients for its leading oncolytic virus product, MVR-T3011, via intravesical administration. The data were presented in a poster at the Conference.

In the study involving 18 BCG-naïve high-risk papillary Ta/T1 NMIBC patients treated with intravesical MVR-T3011 at two dose levels: 2x10⁹ PFU (3 patients) and 1x10¹⁰ PFU (15 patients), preliminary data as of December 31, 2025, demonstrated encouraging efficacy and durability. Among the 14 evaluable patients, the 12-month recurrence-free-survival (RFS) rate was 100% (3/3) at the 2x10⁹ PFU dose level. At the 1x10¹⁰ PFU dose level, the 3-month RFS rate was 100% (11/11). The 6-month and 9-month RFS rates were 75% (3/4) and 66.7% (2/3), respectively, but these data are preliminary, given the small patient numbers reaching those timepoints.

Consistent with BCG-unresponsive clinical data, MVR-T3011 maintained a favorable safety profile in this study with most treatment-emergent adverse events (TEAEs) being at Grades 1 or 2. No treatment-related adverse events (TRAEs) were observed.

Bladder cancer ranks as the ninth most prevalent cancer worldwide^[1], with approximately 75% of cases classified as NMIBC. While Bacillus Calmette-Guerin (BCG) remains the current SOC for high-risk NMIBC, global shortages have limited its availability. As a result, oncolytic immunotherapy, which offers enhanced immune activation and potential durability, is emerging as a promising alternative.

"We are highly encouraged by the preliminary efficacy and safety data from the study," said Dr. Grace Zhou, Chairwoman and CEO of ImmVira. "MVR-T3011 shows its potential to serve as a reliable and widely accessible alternative to BCG, ultimately benefiting patients worldwide."

Source:
1. GLOBOCAN 2022: Bladder cancer 9th most common worldwide

About MVR-T3011

MVR-T3011, represents a breakthrough in HSV-1-based oncolytic immunotherapy. Its proprietary "3-in-1" design unites a replication-competent, tumor-lytic HSV-1 backbone with anti-PD-(L)1 antibody and IL-12, enabling it simultaneously to lyse tumor cells and stimulate innate and adaptive immunity. MVR-T3011 has demonstrated its adaptability and feasibility across multiple routes of administration including intratumoral, intracavitary and intravenous administrations.

About ImmVira

ImmVira is a clinical-stage biotechnology company that is powered by proprietary biological engineering technology, and is dedicated to the discovery, development, manufacture and commercialization of novel oncolytic immunotherapies and engineered exosome therapies. We have strategically designed, self-discovered, and built a risk-balanced product portfolio that comprised two oncolytic immunotherapy candidates for solid tumors and five engineered exosome assets poised for clinical application or direct commercialization. Driven by our vision to become a global leader in the full spectrum of bladder cancer treatment development and unlock the therapeutical potential of oncolytic immunotherapy in head and neck squamous cell carcinoma (HNSCC), we have adopted a rationalized, adaptive approach to advance oncolytic immunotherapy candidates with high clinical potential globally. In parallel, leveraging our deep expertise in biological engineering, we have pioneered development of engineered exosome candidates targeting chronic, hard-to-treat diseases as well as age-related conditions. These selected engineered exosome assets are being accelerated through differentiated regulatory pathways to enable expedited commercialization and generate sustainable cash flows that will fuel our broader drug development efforts.