this is the only number that matters since this is the number the the patients being enrolled in galaxy II.
in clinical trials, it's not uncommon for hr to look good for small sample to only be not confirmed for larger trial size. the fact that hr got worse is somewhat expected. what's important is how meaningful is the change. also to help interpret results, it's important to as if the arms were balance and this is where you look at the cox vs unadjusted hr. the cox hr was 0.55 (0.38, 0.79), p=0.0036 which means the control arm was healthier than the treatment arm.
in summary, galaxy II is likely to be positive with an hr btw 0.55 and 0.61. so this selloff is totally not justified. but since when was the market ever about truth.