US STOCKS-Wall St slips as biotechs drop; Apple shares up
* Apple shares up ahead of results
* Amgen's fall drags downs biotech stocks
* Celladon nosedives on lead drug's trial failure
* Indexes down: Dow 0.04 pct, S&P 0.2 pct, Nasdaq 0.5 pct (Updates to late afternoon)
By Caroline Valetkevitch
April 27 (Reuters) - U.S. stocks edged lower in Monday afternoon trading, led by losses in the Nasdaq and biotech shares including Amgen.
The Nasdaq Biotech Index was down 3.7 percent, on track for its biggest daily percentage loss in about a month, while the S&P Healthcare index, down 1.3 percent, was the biggest drag on the benchmark S&P 500 index.
Amgen shares dropped 3.2 percent to $162.53 after U.S. Food and Drug Administration staff reviewers said Amgen's skin cancer immunotherapy cannot be considered for an accelerated review at this time, citing concerns over the design and results of a key study.
Drug developer Celladon Corp shares fell 80 percent to $2.68 and hit a record low. It said it expected to announce layoffs and cost cuts after the company's lead experimental gene therapy to treat heart failure failed a key trial. Continuación...