Thread by @Timothee_MD

Some toughts about the INDIGO phase 3 trial, vorasidenib in IDH1- or IDH2-Mutant Low-Grade Glioma #ASCO2023

- setting = residual or recurrent disease
- primary EP = PFS = improved from 11.1 to 27.7 Mo (16.6)

Here are some toughts 🧵
1/6

First, we can see that median time from diagnosis ≥ 2.5 years in both groups, so it really looks like mostly recurrent disease.

Now let's make some comparison with another trial, the "PCV trial" -->
This trial was in first-line patients ❗️
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In INDIGO, the primary EP is PFS ...

and OS is a secondary EP which is ... far below in the clinicaltrial.gov list 👇

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in the PCV trial (again, in first-line setting), the primary EP was...

Overall Survival !👏
(and it was a positive trial)
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Crossover in INDIGO
=example of problematic use of crossover.

Why ❓ Because we won't be able to interpret the survival results.

2⃣ false interpretations:
If better = "despite crossover"
If not = "thanks to crossover"

Reality is we won't know : bit.ly/3OSxDUq
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Conclusion:
PCV trial showed a trial with OS = primary EP is feasible in low grade gliomas

vorasidenib = active drug YES

however, mainly bc of crossover, we won't be able to know if it prolongs survival, which I think remain a critical question for patients ❗️

6/6🧵