Agree with you that the primary endpoint for our trial will not be mOS. Thanks for pointing said they will be looking at ORR, objective response rate.
This means we will primarily be looking at whether the tumor size stays the same, shrinks, is eliminated, or grows, acording to RECIST criteria. ORR = percentage of subjects where the tumor shrinks (partial response) or is eliminated (complete response) versus stays the same (stable disease) or grows (progressive disease).
We really are just looking to see if adding LL helps the tumors shrink more than expected.
What is expected? The prior May 2023 NEJM Prager studied showed *very* low response rates:
So, we are looking to beat the ~6% ORR of the combo by adding LL to the cocktail. Not sure what would be a meaningful improvement in ORR.
This primary endpoint or ORR should be found pretty quickly - can tell quickly if tumor responds or not.
You bring up another excellent point, that we are dealing here with MSS CRC. The prior FTD-TPI + bev trial had more of a hodge podge, with ~60% MSS, ~35% unknown, and around 5-10% had MSI-H (high microsatelite instability). That fits with around 5% of metastatic CRC being non-MSS = MSI-H:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7493692/
So, it's a pretty similar comparison group I think. We are just making sure we are dealing with MSS or immunologically cold tumors (no MSI-H), where LL should help keep the T-Regs away and allow the CD8+ killer T-cells in to the tumor microenvironment.
Of course, I am not an oncologist either, and could be wrong!
This means we will primarily be looking at whether the tumor size stays the same, shrinks, is eliminated, or grows, acording to RECIST criteria. ORR = percentage of subjects where the tumor shrinks (partial response) or is eliminated (complete response) versus stays the same (stable disease) or grows (progressive disease).
We really are just looking to see if adding LL helps the tumors shrink more than expected.
What is expected? The prior May 2023 NEJM Prager studied showed *very* low response rates:
Quote:An objective response was observed in 6.1% of the patients in the combination group (95% CI, 3.5 to 9.9), with 15 patients having had a partial response, and in 1.2% of the patients in the FTD–TPI group (95% CI, 0.3 to 3.5), with 1 patient having had a complete response and 2 patients having had a partial response (between-group difference, 4.9 percentage points; 95% CI, 1.6 to 8.2).
So, we are looking to beat the ~6% ORR of the combo by adding LL to the cocktail. Not sure what would be a meaningful improvement in ORR.
This primary endpoint or ORR should be found pretty quickly - can tell quickly if tumor responds or not.
You bring up another excellent point, that we are dealing here with MSS CRC. The prior FTD-TPI + bev trial had more of a hodge podge, with ~60% MSS, ~35% unknown, and around 5-10% had MSI-H (high microsatelite instability). That fits with around 5% of metastatic CRC being non-MSS = MSI-H:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7493692/
So, it's a pretty similar comparison group I think. We are just making sure we are dealing with MSS or immunologically cold tumors (no MSI-H), where LL should help keep the T-Regs away and allow the CD8+ killer T-cells in to the tumor microenvironment.
Of course, I am not an oncologist either, and could be wrong!
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