INDIGO
The first targeted-therapy win in low-grade brain tumours: a pill that more than doubled the time before the tumour grew, delaying radiation and chemotherapy by years.
331 patients. PFS 27.7 vs 11.1 months (HR 0.39); time to next intervention HR 0.26. NEJM 2023; FDA approval August 2024. Long-term OS impact and effect on malignant transformation pending.
Setting
Residual or recurrent grade 2 IDH-mutant astrocytoma or oligodendroglioma after surgery, no prior RT/chemo: vorasidenib vs placebo
Phase
Phase 3
Sponsor
Servier
Registry
Headline result
PFS 27.7 vs 11.1 months, HR 0.39.
Reported
2023
Enrolled
331
Replication
Single pivotal trial; the first targeted therapy in low-grade glioma. Time to next intervention also improved (HR 0.26).
In plain words
What these results mean for people, not percentages
Progression-free survival (BIRC)primarysurrogate endpoint
- Median 27.7 vs 11.1 months with Vorasidenib compared with Placebo; about 16.6 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 61 percent lower chance of the event at any given time (hazard ratio 0.39, likely range 0.27 to 0.56).
- 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: Residual or recurrent grade 2 IDH-mutant astrocytoma or oligodendroglioma after surgery, no prior RT/chemo: vorasidenib vs placebo. People in a different situation may not see the same effect.
- The trial selected people by a biomarker (IDH); 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.
331 participants enrolled.
Progression-free survival (BIRC)primary
HR 0.39 (0.27–0.56) · p <0.001
Vorasidenib
27.7 mo
Placebo
11.1 mo
| Endpoint | Arm | n | Value | HR (95% CI) | p | Source |
|---|---|---|---|---|---|---|
| Progression-free survival (BIRC)primary | Vorasidenib | 168 | 27.7 months | 0.39 (0.27–0.56) | <0.001 | link |
| Placebo | 163 | 11.1 months |
Replication
Single pivotal trial; the first targeted therapy in low-grade glioma. Time to next intervention also improved (HR 0.26).