OncoSec Medical Inc (ONCSQ)

[hschlauch]

Take note of the target population in the keynote-024 trial, the trial for which approval in the first line setting was based - these are NSCLC patients with greater than 50% pdl1 tumor expression. Although they achieved better results than platinum based chemotherapies, they were still only able to achieve a 45% overall response and a 4% complete response. This was a targeted SUBPOPULATION.

So why couldn't even this targeted subpopulation achieve better response rates you ask? After all, the targeted checkpoint was found at a high level of expression in all of these patients. The answer, I believe, is actually related to TIL phenotype expression and quantity. In simpler terms, there just ain't enough pd-1 positive TIL.

Looking at keynote-010 for second line monotherapy keytruda, take note of the overall response rates for pdl1 expression greater than 1% - that is right, only 19%! And of course this does not include patients who don't have any pdl1 expression in their tumors.