ON Q4 and Q1 CC, CEO said less than 50% chance of stop for efficacy, but on Q2 CC, he was more than neutral. From my reading of his comments on Q2 CC, the underline message is very bullish for first look stop, I have never heard a company provide interim look stop conditioning on HR, always on a P value like less than 0.01 or 0.001, HR and P value are related, but not like what He says. Now we know the first look stop for efficacy P is less than 0.02. For example, We may have HR 0.66, but the P value may be 0.01, in this case, OPTIMA may stop for efficacy, this means 99% the HR 0.66 is real compare to the OPTIMA design of HR 0.75, median OS advantage 33% and 80% power at 197 events.
Here is example of interim stop HR and P value with trial assumptions:
Median overall survival was 35.3 months (95% CI, 32.2-NR) for patients receiving XTANDI + LHRH therapy* vs 31.3 months (95% CI, 28.8-34.2) for those receiving placebo + LHRH therapy* (HR = 0.77 [95% CI, 0.67-0.88])
At a prespecified interim analysis for overall survival, XTANDI significantly reduced the risk of death by 29% in patients who received XTANDI + LHRH therapy* vs placebo + LHRH therapy* (HR = 0.71 [95% CI, 0.60-0.84]; P < 0.0001)
The PREVAIL trial was stopped for efficacy on the interim look with above data, OS advantage of 4 months, 35.3 vs 31.3 months, and HR 0.71 risk of death by 29% , but P value less than 0.0001.
By the way, yesterday, Slingshot Insights had a Expert Interview, we may have someone talking about what the expert DR thinking on the OPTIMA results next week after the listeners finishing their positions, IMO. I am expecting very bullish talk from the DR: