Trial results for a Phase 1/2 study evaluating indoximod in combination with immune checkpoint inhibitors, including nivolumab, for adult patients with metastatic melanoma were posted on ClinicalTrials.gov on 2026-05-29. The study reported an Overall Response Rate (ORR) of 3 participants for the indoximod plus nivolumab arm, while the indoximod plus pembrolizumab arm showed an ORR of 67 participants.
Background
This study investigated the IDO inhibitor indoximod in combination with immune checkpoint inhibitors, including nivolumab, ipilimumab, and pembrolizumab. The trial focused on adult patients with unresectable stage III or stage IV melanoma, aiming to evaluate the preliminary efficacy of these combinations. Nivolumab is an established immune checkpoint inhibitor.
Trial design
The Phase 1/2 study (NCT02073123) enrolled 131 participants with metastatic melanoma, stage III melanoma, or stage IV melanoma. The trial evaluated the preliminary efficacy of indoximod in combination with ipilimumab, nivolumab, and pembrolizumab. Efficacy was primarily measured by the best overall response rate (ORR).
Key results
The trial reported the following key measurements:
- Phase 1 Regimen Limiting Toxicity of the Combination of Indoximod and Ipilimumab: 0 participants at Dose Level 1 and 1 participant at Dose Level 2.
- Overall Response Rate (ORR) for Phase 2 arms:
- Indoximod + Ipilimumab: 4 participants.
- Indoximod + Nivolumab: 3 participants.
- Indoximod + Pembrolizumab: 67 participants.
- Overall Survival for the Phase 2: Indoximod + Ipilimumab arm was a median of 29.8 weeks (95% Confidence Interval).
What this means
These Phase 1/2 trial results provide preliminary efficacy data for indoximod in combination with various immune checkpoint inhibitors for metastatic melanoma. The combination of indoximod with pembrolizumab demonstrated the highest Overall Response Rate. The indoximod plus nivolumab arm showed an ORR of 3 participants, while the indoximod plus ipilimumab arm showed 4 participants. The median Overall Survival for the indoximod plus ipilimumab arm was 29.8 weeks. These findings suggest varying efficacy profiles across different combinations, indicating a need for further research into optimal regimens for this patient population.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT02073123, titled "Study of IDO Inhibitor in Combination With Checkpoint Inhibitors for Adult Patients With Metastatic Melanoma", were posted on 2026-05-29 on clinicaltrials.gov.