CheckMate 8HW
Showed that a two-drug immunotherapy combination controls mismatch-repair-deficient bowel cancer for over four years on average, and beats immunotherapy alone.
First-line nivolumab + ipilimumab vs chemotherapy: PFS HR 0.21 (NEJM 2024); at 47 months' follow-up median PFS 54.1 vs 5.9 months. Across all lines, nivolumab + ipilimumab beat nivolumab alone on PFS (Lancet 2025, HR 0.62), the first phase 3 to show the CTLA-4 add-on matters in this setting. FDA approved the combination first line in April 2025. Overall survival is not yet mature.
- Median 54.1 vs 5.9 months with Nivolumab + ipilimumab compared with Chemotherapy; about 48.2 months longer for half the group.
- A median is a midpoint: half the people did better than this and half did worse, so it is not a prediction for any one person.
- Put another way, the treated group had about 79 percent lower chance of the event at any given time (hazard ratio 0.21).
- The treated group had about 38 percent lower chance of the event at any given time (hazard ratio 0.62).
- The absolute difference, how many more people out of 100 were helped, is not reported here.
- This is a surrogate endpoint: it measures the cancer being controlled or absent on scans and tests, which often, but not always, translates into living longer.
- These results apply to the people the trial enrolled: MSI-H/dMMR metastatic colorectal cancer, all lines: nivolumab + ipilimumab vs nivolumab vs chemotherapy. People in a different situation may not see the same effect.
- The trial selected people by a biomarker (MSI-H); the result should not be assumed for people whose cancer does not have it.
Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.
839 participants enrolled.
| Endpoint | Arm | n | Value | HR (95% CI) | p | Source |
|---|---|---|---|---|---|---|
| Progression-free survival, first lineprimary | Nivolumab + ipilimumab | 202 | 54.1 months | 0.21 | — | link |
| Chemotherapy | 101 | 5.9 months | ||||
| Progression-free survival, all lines: combination vs nivolumab | Nivolumab + ipilimumab | 296 | — | 0.62 | — | link |
| Nivolumab | 286 | — |
Pages like this
not linked directly; found by shared links- TrialKEYNOTE-177
Shares Le 2017: mismatch-repair deficiency predicts response to PD-1 blockade across twelve tumour types, leading to the first tissue-agnostic drug approval, Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR), Cold tumours and the immunosuppressive microenvironment, PD-1.
- TrialCheckMate 648
Shares CTLA-4, Ipilimumab, Nivolumab, PD-1.
- TrialCheckMate 9DW
Shares CTLA-4, Ipilimumab, Nivolumab, PD-1.
- IdeaMaking microsatellite-stable colorectal cancer immunotherapy-responsive
Shares CTLA-4, Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR), Cold tumours and the immunosuppressive microenvironment, PD-1.
- Key paperNICHE-2: a single dose of ipilimumab and two of nivolumab before surgery clears dMMR colon cancer in most patients
Shares Le 2017: mismatch-repair deficiency predicts response to PD-1 blockade across twelve tumour types, leading to the first tissue-agnostic drug approval, CTLA-4, Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR), Ipilimumab.
- InstitutionDartmouth Cancer Center
Shares CTLA-4, Ipilimumab, Nivolumab, PD-1.
- TermImmuno-oncology (IO) and checkpoint blockade
Shares Microsatellite-stable (MSS) / mismatch-repair proficient (pMMR), Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR), Ipilimumab, Nivolumab.
- TrialKEYNOTE-006
Shares CTLA-4, Ipilimumab, PD-1.