Great news :Merck (MRK) To Meet With Hemispherx Biopharma (HEB) Following FDA Go Ahead For Expansion Of Ampligen/FluMist Intranasal Clinical Trial Ventures Sierra World Equity Review HEADLINE: Merck (MRK) To Meet With Hemispherx Biopharma (HEB) Following FDA Go Ahead For Expansion Of Ampligen/FluMist Intranasal Clinical Trial Ventures Sierra World Equity Review. Merck (MRK) To Meet With Hemispherx Biopharma (HEB) Sierra believes that Merck and Hemispherx Biopharma will be meeting in Whitehouse Station, New Jersey on Thursday, Sierra's leads are attempting to uncover if Merck is still interested in acquiring Hemispherx Biopharma or if the discussions are more centered towards a partnership. Shares of HED soared over 59% in Monday's session and continued higher in after hours trading