Mendus Reports Positive 2-Year Follow-Up Data for Vididencel Immunotherapy in High-Risk Ovarian Cancer
Key Insights
Mendus AB (search) announced positive 2-year follow-up data from the ALISON Phase 1 trial, confirming safety, tolerability and feasibility of vididencel as an active immunotherapy in high-risk ovarian cancer (search).
Out of 17 patients treated, 8 patients remain alive after 2-year follow-up, with improved tumor-directed immune responses associated with better survival outcomes.
The trial demonstrated no product-related serious side effects, positioning vididencel for potential combination therapies with PARP inhibitors (search), immune checkpoint inhibitors (search) and T cell engagers (search).
Mendus AB (search) has announced positive 2-year follow-up data from the ALISON Phase 1 trial, demonstrating the safety, tolerability and feasibility of its lead immunotherapy vididencel in treating high-risk ovarian cancer (search). The Swedish biopharmaceutical company's results provide a foundation for developing novel combination treatments for this challenging indication.
Trial Results Show Promising Survival Outcomes
The ALISON Phase 1 trial, conducted by the University Medical Center Groningen (UMCG) in The Netherlands, evaluated vididencel's potential to induce clinically relevant immune responses in 17 women diagnosed with late-stage, high-grade serous ovarian carcinoma (search). At a median follow-up of 26 months, 8 patients remained alive and have now passed the 2-year follow-up milestone.
The trial demonstrated improved tumor-directed immune responses (VIR) in 12 out of 17 patients (71%) following vididencel treatment, which were associated with improved progression-free survival. These findings were initially reported at ASCO 2025 and have now been confirmed with extended follow-up data.
Safety Profile Supports Combination Therapy Potential
A key finding from the long-term follow-up was the absence of product-related serious side effects, confirming vididencel's strong safety profile. This safety data positions the immunotherapy as a candidate for combination with other therapeutic modalities.
The correlation between immune responses and clinical outcomes was particularly notable. Stable disease was observed in 5 of 12 patients (42%) with VIR, compared to only 1 of 5 patients (20%) without VIR. Remarkably, 2 patients with VIR maintained stable disease beyond 3.5 years of follow-up.
Addressing Immune Evasion in Ovarian Cancer
"The ALISON long-term follow-up data reveal an interesting correlation between tumor-directed immune responses stimulated by vididencel and progression-free survival in ovarian cancer (search)," said Tariq Mughal, Mendus Chief Medical and Scientific Officer. "Immunotherapy in ovarian cancer has struggled because the disease is associated with multiple immune escape pathways, providing rationale for novel combination treatments to overcome the immune evasion mechanisms by the tumor."
Mughal emphasized that the trial positions vididencel as an active immunotherapy that can be safely combined with other therapeutic modalities such as PARP inhibitors (search), immune checkpoint inhibitors (search) and T cell engagers (search) to establish potential life-saving treatments for this fatal disease.
Future Development Strategy
Mendus and UMCG have established a multi-year collaboration to study novel immunotherapies for gynecological cancers. Beyond the ALISON trial studying vididencel in high-grade serous ovarian cancer (search), the partnership has also developed improved methods for expanding tumor-infiltrating lymphocytes to treat ovarian and endometrial cancers.
As part of its updated clinical strategy, Mendus has indicated that continued clinical development of the gynecological cancer program will be subject to partnering arrangements, suggesting the company is seeking collaborative opportunities to advance these promising therapies.