Trial results for the nextHERIZON study (NCT05311176) investigating IMU-131 in combination with pembrolizumab for patients with metastatic HER2/neu over-expressing gastric cancer were posted on ClinicalTrials.gov on 2025-05-11. The Phase 2 study was terminated, and results for the IMU-131 + Pembrolizumab arm showed 0 participants achieved an objective response.
Background
The nextHERIZON study, formally titled "A Study of IMU-131 (HER-Vaxx) in Combination With Chemotherapy or Pembrolizumab in Patients With Metastatic HER2/Neu Over-Expressing Gastric Cancer," aimed to evaluate this combination in a patient population with advanced gastric cancer. Pembrolizumab (Keytruda) is an immunotherapy drug, while IMU-131 (HER-Vaxx) is an investigational agent.
Trial design
The nextHERIZON study (NCT05311176) was a Phase 2, open-label, 2-Arm, non-randomized study. It was designed as a signal-generating trial in patients with metastatic HER2/neu over-expressing gastric cancer or gastroesophageal adenocarcinomas. The trial's overall status was TERMINATED. The study enrolled a total of 7 participants. Interventions included IMU-131, ramucirumab plus paclitaxel, and pembrolizumab. The combination arm for which results were reported involved IMU-131 + Pembrolizumab.
Key results
Results for the IMU-131 + Pembrolizumab group were reported for safety and efficacy outcomes:
- The number of participants with treatment-emergent adverse events (TEAEs) was 6 Participants.
- The number of participants with immune-related adverse events (irAEs) was 1 Participant.
- The number of participants with objective response was 0 Participants.
For efficacy outcomes such as Overall Survival (OS), Progression Free Survival (PFS), and Duration of Response (DoR), the median values were reported as NA (Not Applicable) in months, with 95% Confidence Intervals also reported as NA.
What this means
The termination of the nextHERIZON trial and the reported results suggest that the combination of IMU-131 and pembrolizumab did not demonstrate sufficient efficacy signals in patients with metastatic HER2/neu over-expressing gastric cancer to warrant further investigation. With 0 participants achieving an objective response among the enrolled patients, the study did not meet its signal-generating objectives for this arm. The "NA" for survival and response duration further indicates a lack of measurable benefit in this small patient cohort.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT05311176, titled "A Study of IMU-131 (HER-Vaxx) in Combination With Chemotherapy or Pembrolizumab in Patients With Metastatic HER2/Neu Over-Expressing Gastric Cancer (nextHERIZON)," were posted on 2025-05-11 on clinicaltrials.gov.