Mendus and UMCG Report Positive ALISON Trial Results for Vididencel in Ovarian Cancer

Press Release: Stockholm, Sweden, December 18, 2024

Mendus AB, a biopharmaceutical company concentrating on immunotherapies that target tumor recurrence, has released promising topline results from its ALISON Phase 1 clinical trial. This trial involves its leading product, vididencel, which is being tested on ovarian cancer patients. The results suggest that vididencel effectively stimulates immune responses against ovarian cancer antigens, paving the way for potential anti-tumor responses. Moreover, the trial results reaffirm vididencel's strong safety profile.

The ALISON trial, a single-center Phase 1 study, was conducted by the University Medical Center Groningen (UMCG) in The Netherlands. This clinical trial is designed to assess the ability of vididencel to trigger significant immune responses in cases of high-grade serous ovarian carcinoma (HGSC). Earlier this year, at the ESMO Gynaecological Cancers conference in June 2024, Mendus and UMCG shared that out of the patients treated with vididencel in the ALISON trial, ten exhibited stable disease while seven showed imaging-confirmed recurrence by the 22nd week.

Upon further analysis of all patient samples, it was observed that 12 out of the 17 patients (71%) who received vididencel showed a vaccine-induced immune response (VIR) against one or more tumor antigens that are typically upregulated in HGSC. This discovery implies a potential groundwork for effective anti-tumor responses. Among the patients without VIR, two out of five (40%) maintained stable disease by week 22, whereas a significant majority with VIR demonstrated stable disease (8 out of 12 patients, or 67%).

Dr. Hans Nijman, Professor of Obstetrics and Gynecology and Head of Immuno-oncology at UMCG, highlighted the severity of ovarian cancer as the most lethal gynecological cancer due to its high recurrence rate. He mentioned that recurring tumors often do not respond to previous treatment lines. Dr. Nijman emphasized that active immunotherapies like vididencel hold potential as they aim to boost immune responses against any remaining disease, potentially improving both disease-free intervals and overall survival rates for ovarian cancer patients post-primary treatment. He expressed optimism regarding further evaluations of vididencel's clinical benefits through extended patient follow-ups in the ALISON trial.

The safety of vididencel was confirmed during the ALISON trial, with patients only experiencing mild adverse effects, primarily localized to the injection site. The trial's long-term follow-up phase is still ongoing, with a subsequent data readout scheduled for the fourth quarter of 2025, following a two-year follow-up period.

Mendus AB is committed to transforming cancer treatment by addressing the challenge of tumor recurrence and enhancing long-term survival rates for cancer patients, all while maintaining health and quality of life. Utilizing their deep understanding of dendritic cell biology, Mendus is developing an advanced clinical pipeline of immunotherapies that promise clinical efficacy alongside a favorable safety profile. The company operates out of Sweden and The Netherlands and is publicly listed on the Nasdaq Stockholm under the ticker IMMU.ST.