Image source: Sarepta Therapeutics.

The stock market took a well-deserved break on Wednesday from its recent volatility, trading in a fairly tight range and finishing the day with mixed results. The Nasdaq Composite posted solid gains of about a third of a percent, but the S&P 500 and Dow Jones Industrials both gave up small fractions of a percentage point. Weakness in the oil market took its toll on energy stocks, and in general, investors appear to be in a holding pattern pending next week's meeting of the Federal Open Market Committee on Tuesday and Wednesday.

Still, even though the overall market stayed close to the flat line, several stocks posted sharp gains, and among the best performers were Sarepta Therapeutics (SRPT 1.27%), Advanced Micro Devices (AMD -2.69%), and Vonage Holdings (VG).

Sarepta could get a quicker decision

Sarepta Therapeutics soared 27% on news that a personnel change within the U.S. Food and Drug Administration might improve the company's chances of having its Duchenne muscular dystrophy treatment approved. The optimism centered on the fact that a team leader within the FDA who had led the review of Sarepta's drug candidate eteplirsen has left the FDA and is no longer listed as an employee within the U.S. Department of Health and Human Services, the overseeing body for the FDA. Analysts noted that this particular reviewer had made negative comments about eteplirsen at the drug's advisory committee, so investors believe his departure could be a positive sign that Sarepta's drug will receive a better reception from the agency in the near future.

AMD gets a boost

Advanced Micro Devices climbed 5% after receiving positive comments from analysts at Deutsche Bank. The bank boosted its price target on AMD stock by 25% to $5, with the analyst report noting that AMD had made comments at Deutsche Bank's recent technology conference. The conference featured comments from AMD Chief Technology Officer Mark Papermaster, who spent a lot of time talking about the Zen x86 CPU and its potential impact on the market starting early next year. With a combination of energy efficiency, core performance, and increased bandwidth, AMD is excited that it could become even more competitive in the microprocessor space and potentially take market share away from some of its rivals going forward.

Vonage makes a connection

Finally, Vonage Holdings gained 5%. The cloud communications company announced the launch of its Nexmo voice application programming interface, which Vonage believes will dramatically improve the quality of enterprise communications as customized for apps, websites, or voice-based communications systems. CEO Alan Masarek heralded the move, noting that it stemmed from Vonage's acquisition of Nexmo earlier this year. With analysts at Robert W. Baird giving an initial rating of outperform on the stock, Vonage investors are excited about the company's potential to drive further growth in the future.