BOSTON ( TheStreet) -- The fall will be a very busy time for U.S. drug approvals. For this latest update to my regulatory calendar, I count 21 drugs (impacting 27 different drug and biotech companies) with approval applications to be decided before year's end by the regulators at the U.S. Food and Drug Administration. In October alone, the FDA is expected to render approval decisions on 10 drugs. This FDA regulatory calendar includes information on both drug-approval decisions dates as well as dates for any upcoming FDA drug advisory panels. Stocks are listed in chronological order, based on the nearest regulatory catalyst. Questcor Pharmaceuticals ( QCOR) Drug/indication: Acthar for infantile spasms Approval decision date: Sept. 11, 2010 Recent stock performance:At $10.69, the stock is just below its 52-week high of $11.63 reached July 30. An FDA advisory panel said Acthar was safe and effective as a treatment for infant spasms at a meeting on May 6. The original FDA approval decision date of June 11 was extended by three months so that the agency could drug labeling and post-approval commitments. Savient Pharmaceuticals ( SVNT) Drug/indication: Krystexxa for gout Approval decision date: Sept. 14, 2010 Recent stock performance:At around $14, the stock is up about 30% since early June. The FDA refused to approve Krystexxa last August, citing problems with the way the drug is manufactured. Savient revised the Krystexxa manufacturing process and submitted a response in March to the FDA's complete response letter. Alkermes ( ALKS) Drug/indication:Vivitrol for opioid addiction FDA advisory panel: Sept. 16, 2010 Approval decision date: Oct. 12, 2010 Recent stock performance:At just under $14, the stock is up about 45% for the year. If approved, Vivitrol will be the first long-acting, non-narcotic treatment for patients addicted to opioids. Alkermes currently sells a version of Vivitrol for alcholol dependence.