FDA Accepts Complete Response Submission Regarding the Ampligen New Drug Application for Chronic Fatigue Syndrome

Hemispherx Biopharma, Inc.

(the "Company" or "Hemispherx") filed on July 31, 2012 with the U.S. Food and Drug Administration its complete response to the FDA's November 25, 2009 Complete Response Letter in support of Ampligen^®'s New Drug Application for Chronic Fatigue Syndrome ("CFS"). (Please see the Company's press release and Form 8-K dated August 1, 2012.) On August 10, 2012, the FDA acknowledged in writing receipt of the Company's August 1, 2012, response stating, "We consider this a complete, class 2 response to our November 25, 2009, action letter. Therefore, the user fee goal date is February 2, 2013."