Shares of BioCryst Pharmaceuticals Inc. (BCRX) - Get Report jumped 0.5% to $5.30 in early trading on Thursday, Sept. 21, after the Research Triangle Park, N.C.-based firm clinched approval from the U.S. Food and Drug Administration for its supplemental new drug application for Rapivab (peramivir injection). This extends its availability to treat acute uncomplicated influenza to pediatric patients 2 years and up that have been symptomatic for no more than two days.

The approval marks "the first new influenza antiviral for pediatric use in over 10 years," said BioCryst president and CEO Jon P. Stonehouse in the news release.

Meanwhile, shares of Amphastar Pharmaceuticals Inc. (AMPH) - Get Report rose 4.4% to $16.32 after the FDA approved the Rancho Cucamonga, Calif.-based firm's abbreviated new drug application for sodium bicarbonate injection 8.4% in the 50 mL Luer-Jet prefilled syringe system.

Amphastar said it has sold and marketed the product for the past 40 years under the "grandfather" exception to the FDA's "Prescription Drug Wrap-Up" program.

Among the other biotech stock movers was Juno Therapeutics Inc. (JUNO) , down 2.3% to $44.81. The Seattle firm after the market close on Wednesday said it launched a follow-on public offering of $225 million of shares. Juno also plans to give underwriters a 30-day option to buy up to an additional $33.75 million of shares.

Juno said it plans to use the net proceeds for general corporate purposes and working capital.

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