UPDATE: Piper Jaffray Downgrades Arena Pharmaceuticals to Neutral

Piper Jaffray cuts its rating on Arena Pharmaceuticals

ahead of AdCom and following the recent surge in shares. Price target is kept at $2.50. Piper Jaffray says, "Shares of ARNA have surged 60% since last Thursday's close and +157% since the end of November 2011. While we continue to believe that Arena has addressed the six issues raised in the Complete Response Letter (

) for lorcaserin, we see the risk:reward having shifted as a result of the recent price performance. We are thus downgrading Arena to Neutral and maintaining our $2.50 price target going into the May 10 AdComm. While shares of ARNA could still trade significantly higher on a positive panel vote, we see downside risk back to the $1 level if negative." ARNA closed at $3.26 a share on Tuesday.