The markets opened flat with the Dow adding 5 points to 18,317 ahead of the release of Federal Reserve meeting minutes. Nasdaq slipped 4 points to 5,065.

On the upside

Prima Biomed (Nasdaq: PBMD) reported positive results from a Phase II clinical trial of its ovarian cancer treatment CAN-003.

Sarepta Therapeutics (Nasdaq: SRPT) will submit a rolling New Drug Application for its Duchenne muscular dystrophy treatment eteplirsen.

The Food and Drug Administration granted Orphan Drug Designation and Rare Pediatric Disease Designation to PlasmaTech Biopharmaceuticals' (Nasdaq: PTBI) ABX-101 and ABX-102.

On the downside

Achillion Pharmaceuticals (Nasdaq: ACHN) entered a worldwide license and collaboration agreement with Janssen Pharmaceuticals to develop one of Achillion's hepatitis C virus treatments but the stock price fell after rumors that Gilead (Nasdaq: GILD) was buying Achilion were quashed.

Etsy (Nasdaq: ETSY) reported an unexpected loss for the first quarter.

Lpath (Nasdaq: LPTN) reported disappointing results from a Phase 2 Nexus clinical trial of its wet age-related macular degeneration medication iSONEP. In light of the results, the company will reduce its workforce.

In the broad market, declining issues outpaced advancers by a margin of nearly 5 to 4 on the NYSE and by nearly 5 to 3 on Nasdaq. The broader S&P 500 eased a point to 2126. Bitcoin added $1 to $233.