UPDATE 2-Aeterna hits record low after FDA rejects growth hormone test
* FDA says not enough "verifiable" data, asks for fresh trial
* FDA says drug could have led to a cardiac event in trial
* Canaccord cuts drug's success chance to 40 pct from 85 pct
* Toronto- and U.S.-listed stock fall over 50 percent (Adds detail, analyst comment; updates shares)
Nov 6 (Reuters) - Canada's Aeterna Zentaris Inc said the U.S. Food and Drug Administration rejected macimorelin, which the drugmaker had hoped would be the first orally administered drug to determine if adults had growth hormone deficiency.
The company's Toronto-listed and U.S.-listed shares both fell by more than half to record lows on Thursday.
An analysis showed the company's key trial did not meet its main efficacy goal and there was not enough "verifiable" data used to diagnose adult growth hormone deficiency (AGHD), the FDA said in a complete response letter to Aeterna.
The agency also said the drug's involvement in a serious cardiac event during the trial could not be ruled out and asked Aeterna to conduct fresh trials to demonstrate the effectiveness and safety of macimorelin.
Canaccord Genuity slashed its estimate of the drug's chances of success to 40 percent from 85 percent, based on its enhanced risk profile, and said the launch has likely been pushed out by about four years. Continued...