AZUR-1
A Phase 2, Single-Arm, Open-Label Study With Dostarlimab Monotherapy in Participants With Untreated Stage II/III dMMR/MSI-H Locally Advanced Rectal Cancer
Phase 2N = 154NCT05723562
- Population
- Adults with previously untreated, histologically confirmed MSI-H/dMMR stage II (T3-T4, N0) or stage III (any T, N+) locally advanced rectal cancer, with endoscopically and radiologically evaluable disease
- Design
- Multicentre, single-arm, open-label phase 2 trial (the design report describes about 150 patients across 10 countries; 154 were treated). Dostarlimab 500 mg intravenously every 3 weeks for 9 cycles. Tumour response was assessed by endoscopy, rectal MRI and CT of the chest, abdomen and pelvis at week 6 (endoscopy only), week 12 and about 3 weeks after treatment. Patients with a clinical complete response (cCR) at either of the first two post-treatment assessments entered non-operative management, with surveillance every 4 months for the first 2 years and every 6 months thereafter; patients without cCR, or whose disease recurred or progressed, were evaluated for standard-of-care management at investigator discretion. Primary efficacy outcome: sustained cCR for 12 months (cCR12) by independent central review. The figures below are the interim analysis in the FDA prescribing information (data cutoff 20 April 2026); the FDA record does not cite a peer-reviewed report of these results.
- Primary endpoint
- Sustained clinical complete response at 12 months
- Arms
- Dostarlimab (experimental, n = 154): Dostarlimab 500 mg intravenously every 3 weeks for 9 cycles
- People
- Cercek A
Show the numbers
| Endpoint | Analysis | Dostarlimab | Control | Effect |
|---|---|---|---|---|
| Sustained clinical complete response at 12 monthsPatients evaluable for cCR12 by independent central review: 116 of 154 (those with an opportunity for at least 12 months of follow-up from the first response showing cCR)Sustained clinical complete response for 12 months (cCR12) per independent central review (primary efficacy outcome), measured from the first assessment after the last dose at which cCR was observed | interimmedian follow-up 26 monthsSource 2026 | 47% (37–56%) | — | 54 of 116 evaluable patients. A further 38 patients had a cCR by central review and had less than 12 months of follow-up at the cutoff. The label gives the interval as (37, 56), Clopper-Pearson; the FDA web notice prints the lower bound as 27%, which does not match the label (an exact binomial interval for 54 of 116 is about 37% to 56%), so the label value is used. |
| Sustained clinical complete response at 12 monthsPatients evaluable for cCR12 by investigator assessment: 144 of 154 (94%)cCR12 based on investigator tumour response assessments (additional efficacy outcome) | interimmedian follow-up 26 monthsSource 2026 | 68% (60–76%) | — | 98 of 144 evaluable patients. Clopper-Pearson interval as printed in the label. |
| ORRAll 154 treated patientsObjective response at the first or second assessment after dostarlimab per independent central review (additional efficacy outcome); in the label's table the responses are cCR, clinical near-complete response and partial response | interimmedian follow-up 26 monthsSource 2026 | 79% (71–85%) | — | 121 of 154 patients by central review (cCR 43, near-complete response 44, partial response 34). By investigator assessment the objective response rate was 82% (95% CI 75 to 88; 126 patients). |
| No further treatment and no progression or relapseAll 154 treated patientsPatients who did not receive further oncological treatment after dostarlimab and had not progressed or relapsed at the interim analysis | interimmedian follow-up 26 monthsSource 2026 | 71% | — | 110 of 154 patients. Of the others, 26 (17%) had surgery (with or without additional systemic therapy or radiation), 13 (8%) had additional systemic therapy or radiation, 1 (0.6%) had progressive disease without further treatment and 4 (2.5%) withdrew or were lost to follow-up. Six patients had died at the cutoff: four with progressive disease and no initial response, one from sepsis after treatment for intestinal obstruction, and one after withdrawal from the study. The FDA notice reports a median follow-up of 26.3 months and that none of the patients with cCR12, cCR or near-complete response had disease progression. |
| Endpoint | Analysis | Dostarlimab | Control | Effect |
|---|---|---|---|---|
| Sustained clinical complete response at 12 monthsPatients evaluable for cCR12 by independent central review: 116 of 154 (those with an opportunity for at least 12 months of follow-up from the first response showing cCR)Sustained clinical complete response for 12 months (cCR12) per independent central review (primary efficacy outcome), measured from the first assessment after the last dose at which cCR was observed | interimmedian follow-up 26 monthsSource 2026 | 47% (37–56%) | — | 54 of 116 evaluable patients. A further 38 patients had a cCR by central review and had less than 12 months of follow-up at the cutoff. The label gives the interval as (37, 56), Clopper-Pearson; the FDA web notice prints the lower bound as 27%, which does not match the label (an exact binomial interval for 54 of 116 is about 37% to 56%), so the label value is used. |
| Sustained clinical complete response at 12 monthsPatients evaluable for cCR12 by investigator assessment: 144 of 154 (94%)cCR12 based on investigator tumour response assessments (additional efficacy outcome) | interimmedian follow-up 26 monthsSource 2026 | 68% (60–76%) | — | 98 of 144 evaluable patients. Clopper-Pearson interval as printed in the label. |
| ORRAll 154 treated patientsObjective response at the first or second assessment after dostarlimab per independent central review (additional efficacy outcome); in the label's table the responses are cCR, clinical near-complete response and partial response | interimmedian follow-up 26 monthsSource 2026 | 79% (71–85%) | — | 121 of 154 patients by central review (cCR 43, near-complete response 44, partial response 34). By investigator assessment the objective response rate was 82% (95% CI 75 to 88; 126 patients). |
| No further treatment and no progression or relapseAll 154 treated patientsPatients who did not receive further oncological treatment after dostarlimab and had not progressed or relapsed at the interim analysis | interimmedian follow-up 26 monthsSource 2026 | 71% | — | 110 of 154 patients. Of the others, 26 (17%) had surgery (with or without additional systemic therapy or radiation), 13 (8%) had additional systemic therapy or radiation, 1 (0.6%) had progressive disease without further treatment and 4 (2.5%) withdrew or were lost to follow-up. Six patients had died at the cutoff: four with progressive disease and no initial response, one from sepsis after treatment for intestinal obstruction, and one after withdrawal from the study. The FDA notice reports a median follow-up of 26.3 months and that none of the patients with cCR12, cCR or near-complete response had disease progression. |
Appears in
Sources
Cercek A, Bachet JB, Capdevila J, Starling N, Chen E, Salvatore L, et al. A Phase Two, Single-Arm, Open-Label Study With Dostarlimab Monotherapy in Participants With Untreated Stage II/III dMMR/MSI-H Locally Advanced Rectal Cancer (AZUR-1). Clin Colorectal Cancer. 2025;24(2):325-330.
FDA. Prescribing information, Jemperli (dostarlimab-gxly) injection, labeling approved with BLA 761174/S-015 (revised 10/2026).