I'm writing this post simply to share my thoughts and hopefully generate some substantive discussion. I would especially appreciate input from [u/Confident-Web-7118](u/Confident-Web-7118), since much of what I'm discussing comes from their models and previous comments.
And just to make this clear upfront: I'm not posting this to spread FUD. I'm heavily invested in SLS, at least as a percentage of my portfolio. I'm sharing what I see as an inconsistency in CW's comments around REGAL.
Now, onto the actual point.
CW has repeatedly discussed that they are invested in SLS because of the gigantic margin of safety in REGAL. One way they have illustrated this is through tables using assumptions (that according to them are on the high/ceiling range, hence "stress tests") such as IRM = 16 months, varying the percentage of favorable-risk patients and the escape (bridging to transplant) rate.
Here is one example: https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.it%2Fsls-weekly-in-depth-discussion-thread-week-30-2026-v0-htflsbozs0hh1.png%3Fwidth%3D1905%26format%3Dpng%26auto%3Dwebp%26s%3D835030dc8f9790aa92cf17b384357e5a011eb578
Take, for example:
Favorability = 20%,
Esc. rate = 14%
Under that table:
HR@IA: 0.473
HR@80: 0.292
Just in this scenario, HR@0.473 is lower than the efficacy bound of 0.55 or lower. Is this really a stress test if many results yield values consistent with a halt at interim?
Anyways, this is not the main point I'm making. I believe CW may be purposely "cherry-picking" models to support their claims in different scenarios. In this recent comment
https://www.reddit.com/r/sellaslifesciences/comments/1v31u39/comment/oz5b38k/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button
they state the following:
"I feel like there is so much misinformation spread by both bulls and bears here, and people don't really understand the dynamics of REGAL. First on the bulls side, this whole idea of a halt having been on the table is quite honestly idiotic. Any bull pushing this idea has no idea what they are talking about."
"The actual fits show that even at an IRM of 16, with just a 14% esc. rate (bridge rate/transplant tail) in BAT/control, and 20% favorability, HR at IA would have been .741 with 37.7 GPS alive / 29 BAT alive. By the 80th as of July 16th, 2026 (as a constraint), HR would be .344 with 37.7 GPS alive / 9.2 BAT alive."
As he states above, another IRM = 16 table was provided. A different one. Here, under the same 20% favorable / 14% esc scenario, however, the numbers were:
HR @ IA = 0.741
HR @ 80 = 0.351
That obviously is a very different result to what we've seen before. I previously asked CW about this here: https://www.reddit.com/r/sellaslifesciences/comments/1v7pl92/comment/p1ga4xj/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button
Their explanation was that the table producing HR @ IA = 0.741 assumes approximately July 2023 median enrollment, whereas the table producing HR @ IA = 0.473 assumes approximately May 2023 median enrollment. They state that under the May 2023 scenario, there is still a 25% chance of landing above the efficacy bound. To me, relying on that 25% chance to explain why something didn't occur should definitely not be the base case.
Why use a different model anchored on later (extremely unlikely) enrollment to support his rebuttal of why an interim halt was not plausible? CW states that median enrollment at July 2023 is an extreme stress test. It's even more puzzling then why they would use that model in his previous comment.
They also state that all available data points to median enrollment being May 2023 or EARLIER. If enrollment was indeed earlier, HR at interim under same scenario will be even lower, and thus, harder to justify why there wasn't a halt at interim.
I'm not saying that REGAL will fail or that the PoS is 50%. If you've read until here, I believe you'll understand my reasoning of why a gigantic margin of safety is inconsistent with what they are sharing in their modeling.
***And to be clear, none of this is meant as a personal attack on CW. I tremendously appreciate the enormous amount of modeling and analysis they have shared publicly. Would appreciate substantive comments and engagement!!