Forget about exclusion. Just forget about it for now.
The point is, you have to know if the ECA is or is not loaded with idh1 mutant. You can’t match if you don’t know what the ECA has. It puts DCVax-l in a risky situation. It’s like tying both arms behind DCVax-l’s back, and giving the ECA a running head start. They know the percentage (probably very low) of idh1 mutants in the DCVax-l trial. How can they create an ECA match if they don’t know idh1 status? I highly doubt they did this.