One-sided significance threshold of less than 0.1 in Phase 2 clinical trial

As an aside - I am often curious about how many phase 2 trials actually end up, after further trials, with a clinically useful intervention. It probably depends on the field. This affects how we could interpret the p-values. For example, if 50% of phase 2 trials are of a new drug that is really better than the current drug (we just don’t know which 50%), then for alpha 0.1 and beta 0.8 (say) out of 100 trials, 5 would be FP, 45 TN, 40 TP, 10 FN - so a positive result would have a 40/45 probability of being TP and a negative a 45/55 probability of being a TN (though maybe we could make better estimates if we use the actual p-value post-hoc). I guess we don’t have the data needed to interpret this way (also I guess 50% is very optimistic - in one field I know the current rate is 0%!).