NEW YORK ( TheStreet) -- Several stocks trading near $5 were poised to move on above-average volume during Wednesday's session. Dyax ( DYAX) surged by 95 cents, or 27.1%, to $4.45 in the premarket session after the biotech company received full approval from the Food and Drug Administration to market Kalbitor for the treatment of acute attacks of hereditary angiodema (HAE). The 50-day average daily volume for Dyax is 540,000, according to the Nasdaq. Novavax ( NVAX - Get Report) jumped by 26 cents, or 8.1%, to $3.21 in the premarket session after the company reported "positive" clinical results from a pivotal Phase II study of its H1N1 influenza vaccine in Mexico. The 50-day average daily volume for Novavax is 3.9 million. Santarus ( SNTS) rallied by $1.07, or 25%, to $5.36 in the premarket session after the company and partner Merck ( MRK) announced that the FDA has approved Zegerid capsules for over-the-counter treatment of frequent heartburn. Investment firms Thomas Weisel and Roth offered positive comments on Santarus following the FDA approval, with the latter offering a $7.50 stock price target. The 50-day average daily volume for Santarus is 259,000. Smith & Wesson ( SWHC) rose by 14 cents, or 2.6%, to $5.54 in the premarket session a day before the company was set to report fiscal second-quarter earnings. Both Wedbush Morgan and Merriman Curhan Ford put out research notes on the company Wednesday, expecting upside results as the company works through its firearms backlog due to an increase in gun sales. The 50-day average daily volume for Smith & Wesson is 1.3 million. RF Micro Devices ( RFMD) added 17 cents, or 3.6%, to $4.68 in the premarket session after UBS upgraded the company's stock to buy from neutral. The 50-day average daily volume for RF Micro is 9.2 million. -- Written by Robert Holmes in New York. Check out all of Wednesday's high-volume, under-$5 stocks at the Dollar Store Follow Robert Holmes on Twitter and become a fan of TheStreet.com on Facebook.