"So, back to that primary endpoint. Is that endpoint sufficiently ambitious in A's trial to assume that it being met is strong evidence of overall success?"
Yes. This is a high-risk population. As far as I know of, no CVOT in a population of diabetic patients with recent ACS has shown MACE reduction. EXAMINE and ELIXA both failed. If BETonMACE shows significant MACE reduction in this high-risk population, it will be huge. The AHA 2018 poster indicated that "With an assumed primary event rate of 7 per 100 patient years in the placebo group, the study has 80% power to detect a 29% reduction in MACE with ABL (or 50% power to detect a 24% reduction) with 2400 patients and an average exposure of 1.5 years." So most likely if the %RRR is significant, BETonMACE will have achieved a 24% or better RRR. The %RRR could still be a bit lower and still be significant. But hopefully it is much higher! So a top-line news release indicating that BETonMACE achieved the primary endpoint without revealing a %RRR........I'd be expecting anywhere between 15% and 50% RRR. Hopefully on the higher end!
BearDownAZ