Mizuho On Atara Biotherapeutics - Distinguish Between Small Numbers And Science Failure - Atara Biotherapeutics (NASDAQ:ATRA)

Atara Biotherapeutics Inc ATRA issued its anticipated interim analysis communication for its ATA188 Phase 2 progressive multiple sclerosis trial. Shares slumped over 50%.
Mizuho thinks that investors need to make a clear distinction as they reassess their position after these inconclusive results and no-sample-size adjustment communication.
Is there any new risk with the actual science and data itself? Mizuho writes:
The interim data was based mainly on the Phase 1 data, which showed that six-month EDSS improvement was >85% predicative of that at 12 months. But the study itself was small, with only 24 patients.
Data was even smaller, with EDSS data on 34 patients at six months and 15 patients at twelve months.
The analyst notes dose and time-dependent response from the single-arm ATA188 Phase 1, sustained disability EDSS improvement in the 33-50% range in the higher dose cohorts, and similar data from autologous sister compound ATA190.
Mizuho keeps the price target at $39 with a Buy rating.
Price Action: ATRA shares are down 55% at $3.90 during the market session on the last check Wednesday.