ImmVira Reports 100% Complete Response Rate at 9 Months in Bladder Carcinoma in Situ with MVR-T3011 at ASCO

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May 31, 2026, 20:00 ET

SUZHOU, China, May 31, 2026 /PRNewswire/ -- ImmVira Group ("ImmVira") today announced that preliminary Phase IIa clinical data for MVR-T3011, its lead oncolytic immunotherapy candidate, was presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting. As of the data cut-off on January 31, 2026, the optimized dose of MVR-T3011 achieved a 100% complete response rate (CRR) in BCG-unresponsive carcinoma in situ (CIS) and a durable 90% recurrence-free survival (RFS) in papillary (Ta/T1) tumors^[1].

While intravesical instillation of Bacillus Calmette-Guérin (BCG) remains the standard of care for high-risk NMIBC-representing 75% of all newly diagnosed bladder cancer cases, a global BCG shortage and high rates of non-response leave a significant patient population without effective options. MVR-T3011 was developed with the goal of delivering potent local and systemic anti-tumor immunity directly within the bladder, offering a potential organ-preserving treatment option for this high-need population.

The ongoing trial enrolled 46 patients in total with pathologically confirmed BCG-unresponsive high-risk NMIBC. Patients received intravesical MVR-T3011 at one of two dose levels:

Lower-dose group (2×10⁹ PFU): Induction course followed by maintenance dosing over two years (n=25).
Higher-dose group (1×10¹⁰ PFU): Induction course followed by maintenance dosing over two years (n=21).

The results demonstrate that MVR-T3011 achieved meaningful clinical efficacy and a favorable safety profile across both carcinoma in situ (CIS) and papillary (Ta/T1) disease settings：

In the CIS cohort, the higher-dose 1×10¹⁰ PFU regimen achieved a 100% complete response rate (CRR) at 3 months, 6 months, and 9 months, as well as at any assessed timepoint— a marked step up from the lower-dose 2×10⁹PFU cohort, which achieved a 66.7% CR rate at any timepoint (with timepoint-specific CRRs of 55.6% at 3 months and 75.0% at 6 months). The 12-month CRR for the 1×10¹⁰ PFU cohort has not yet been reached, with follow-up ongoing.
In the papillary (Ta/T1) cohort, the 2×10⁹ PFU dose delivered a durable 12-month recurrence-free survival (RFS) of 74.0%, an already strong outcome; at the higher 1×10¹⁰ PFU dose, 9-month RFS reached 90.0%, with longer-duration follow-up ongoing.

Across all 46 patients treated, MVR-T3011 demonstrated a manageable safety profile consistent with prior observations. Importantly, the higher-dose 1×10¹⁰ PFU cohort showed a safety profile consistent with the lower-dose 2×10⁹ PFU cohort, with no Grade 4 or 5 TEAEs reported across either dose level, or no deaths attributable to treatment.

"The presentation of these Phase IIa results at ASCO 2026 marks a meaningful milestone for ImmVira and for the broader NMIBC community," said Dr. Grace Zhou, Chairwoman and CEO of ImmVira. "MVR-T3011 has demonstrated great therapeutic potential through both direct anti-tumor activity in CIS and immune suppression in papillary (Ta/T1) disease. This represents a synergy of direct oncolysis and immune activation, further enhanced by the integrated effects of exogenous IL-12 and PD-1 antibody expressions within tumor cells. We are committed to rapidly advancing our clinical program to reach broader bladder cancer patient populations and provide meaningful treatment alternatives for those in need.

[1] Due to the small sample size and the early, interim nature of the data, the observed CRR and RFS are subject to statistical uncertainty and are inherently susceptible to change as patient enrollment continues and follow-up matures. These preliminary results should not be construed as an indication of the final outcomes of the current study, nor should they be regarded as predictive of results that may be achieved in a future confirmatory phase III clinical trial or in connection with any regulatory review or approval.

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.

SOURCE ImmVira Group