Shares of Rigel Pharmaceuticals Inc. (RIGL) - Get Report rose nearly 19% to $3.02 ahead of the market open on Monday, Oct. 2, after the South San Francisco, Calif.-based firm said the U.S.  Food and Drug Administration indicated that it does not plan to conduct an Oncology Drugs Advisory Committee meeting to discuss Rigel's new drug application for fostamatinib in chronic or persistent immune thrombocytopenia.

The FDA also indicated that it anticipates meeting the Prescription Drug User Fee Act action date of April 17, 2018 for the application review, Rigel said.

Meanwhile, shares of Seres Therapeutics Inc. (MCRB) - Get Report were down 11.5% to $14.20 despite reporting positive topline results from a Phase 1b placebo-controlled induction study of SER-287 in patients with mild-to-moderate ulcerative colitis. The Cambridge, Mass.-based company also said that the SER-287 safety and tolerability profile "demonstrated no clinically significant safety findings."

Among the other biotech stock movers was Seattle Genetics Inc. (SGEN) - Get Report . Shares were up 5.9% to $57.60 after the Bothell, Wash.-based company received breakthrough therapy designation from the FDA for Adcetris (brentuximab vedotin) in tandem with chemotherapy for the frontline treatment of patients with advanced classical Hodgkin lymphoma.

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