Comment by Kalanos

It's a checkpoint inhibitor. Those have been used for ~ every cancer type for over a decade. Keytruda has been a top-selling drug for years.

It looks like this trial was neoadjuvant (before treatment/ alternative to chemo and surgery), but that's not new either.

immunotherapy typically has much lower response rates though, so maybe it's the mismatch repair selection strategy that's novel

at a sample size of 12... they could have gotten lucky