If I'm not mistaken, there are zero prior data for efficacy at the 120 dose for HCC
I believe you are correct.
Also, how did they come up with the conclusion to reduce to 120 mg? If they thought 120 mg would have given them a good efficacy read with favorable AEs, why didn't they use 120 mg in the first place instead of using a dose 100% higher?
It's like they begged the DMC to do anything at all just so they wouldn't have to stop the trial completely. Just how bad could the neutropenia have been this early in the trial for the DMC to make this recommendation?? Must have been pretty significant.
there are zero prior data for efficacy at the 120 dose for HCC
Not entirely accurate. In most oncology trials, there are always experience with dose reduction depending on drug tolerability, thus some sort of data on lower dose exist. In ph2 HCC trial, 30% patients in 240mg bid arm got dose reduction, presumably to 120mg bid. In the case of EXEL's cabo when they first tried to test lower dose, they picked 60mg as starting test dose mainly because 60mg was the dose reduction they used extensively in RDT trial. So they were pretty close in their assessment. However, tivan HCC ph2 trial was small and dose reduction in 240mg bid arm wasn't extremely high, thus no where near as much data as cabo RDT where trial was much larger with higher percentage of dose reduction.
Apologies if "disappointing" from my prior post didn't suffice.
If I'm not mistaken, there are zero prior data for efficacy at the 120 dose for HCC upon which we can extrapolate for the phase 3. I'm surprised that people are actually discussing this situation rather than running away screaming.
I don't think it's in the newbie rules but there's gotta be one added that says something like "Never bet on a phase 3 that is using a drug at a dose for which there are no prior data."
Has EXEL's cabo (also a MET inhibitor, among other targets) not seen continued efficacy at much lower doses than originally tested? Notwithstanding, as I said, I am now skeptical on chances of success for tivantinib in P3 HCC trial. But, I'm not going to assign zero value either as there's still a chance it could work and there's also still a chance in other indications. But, most importantly for me is the fact that ARQL barely trades above cash now and has other assets beyond tivantinib in wholly-owned AKT and FGFR inhibitors in ongoing Phase 1 trials. That is a risk-reward that works for me personally so I'll continue to hold, for better or worse.