Note 1 - Company Overview	3 Months Ended
Sep. 30, 2013
Disclosure Text Block [Abstract]
Nature of Operations [Text Block]	(1) Company Overview Biota Pharmaceuticals, Inc., together with its wholly owned subsidiaries (“Biota”, or the “Company”) is a biopharmaceutical company focused on the discovery and development of products to prevent and treat serious and potentially life-threatening infectious diseases. The Company has been incorporated in the state of Delaware since 1969 and the corporate headquarters are located in Alpharetta, Georgia. On November 8, 2012, Nabi Biopharmaceuticals (“Nabi”) merged with Biota Holdings Limited, which was previously listed on the Australian Stock Exchange (ASX:BTA), and the resulting company was renamed to Biota Pharmaceuticals, Inc. The Company currently has two Phase 2 clinical-stage product candidates; laninamivir octanoate, for the treatment of influenza A and B infections in the U.S. market; and vapendavir (“BTA798”), a potent, oral broad-spectrum capsid inhibitor of enteroviruses, including human rhinovirus (“HRV”). In addition, the Company has preclinical programs focused on developing treatments for respiratory syncytial virus (“RSV”) as well as for gram-negative and multi-drug resistant bacterial infections. The Company has developed a neuraminidase inhibitor (“NI”), zanamivir, which is marketed worldwide by GlaxoSmithKline (“GSK”) as Relenza® for the prevention and treatment of influenza under a research and license agreement entered into with the Company in 1990. In addition, the Company and Daiichi Sankyo Inc. have cross-licensed the world-wide rights to develop and commercialize long-acting neuraminidase inhibitors (“LANI’s”), including laninamivir octanoate, which is marketed by Daiichi Sankyo Inc. as (“Inavir”) in Japan for the treatment of influenza A & B infections in adults and children. In November 2012, Daiichi Sankyo submitted an application for Japan to manufacture and market Inavir® for the prevention of influenza infection. The Company has filed an Investigational New Drug application (“IND”) with the United States Food and Drug Administration (“FDA”) to develop laninamivir octanoate in the U.S., and in 2011 the Company was awarded a contract from the U.S. Office of Biomedical Advanced Research and Development Authority (“BARDA”) designed to provide up to $231.2 million in support of the development of and submission for a new drug application (“NDA”) of laninamivir octanoate for the treatment of influenza A and B infections in the United States. Although several of the Company’s influenza products have been successfully developed and commercialized by other larger pharmaceutical companies under license agreements, the Company has not received regulatory approval for any product candidates it has developed independently, and does not have any sales, marketing or commercial capabilities. Therefore, it is possible that the Company may not successfully derive any significant product revenues or earnings from any of its existing or future development-stage product candidates.

Note 1 - Company Overview

3 Months Ended

Sep. 30, 2013

(1) Company Overview

Biota Pharmaceuticals, Inc., together with its wholly owned subsidiaries (“Biota”, or the “Company”) is a biopharmaceutical company focused on the discovery and development of products to prevent and treat serious and potentially life-threatening infectious diseases. The Company has been incorporated in the state of Delaware since 1969 and the corporate headquarters are located in Alpharetta, Georgia. On November 8, 2012, Nabi Biopharmaceuticals (“Nabi”) merged with Biota Holdings Limited, which was previously listed on the Australian Stock Exchange (ASX:BTA), and the resulting company was renamed to Biota Pharmaceuticals, Inc.

The Company currently has two Phase 2 clinical-stage product candidates; laninamivir octanoate, for the treatment of influenza A and B infections in the U.S. market; and vapendavir (“BTA798”), a potent, oral broad-spectrum capsid inhibitor of enteroviruses, including human rhinovirus (“HRV”). In addition, the Company has preclinical programs focused on developing treatments for respiratory syncytial virus (“RSV”) as well as for gram-negative and multi-drug resistant bacterial infections.

The Company has developed a neuraminidase inhibitor (“NI”), zanamivir, which is marketed worldwide by GlaxoSmithKline (“GSK”) as Relenza® for the prevention and treatment of influenza under a research and license agreement entered into with the Company in 1990. In addition, the Company and Daiichi Sankyo Inc. have cross-licensed the world-wide rights to develop and commercialize long-acting neuraminidase inhibitors (“LANI’s”), including laninamivir octanoate, which is marketed by Daiichi Sankyo Inc. as (“Inavir”) in Japan for the treatment of influenza A & B infections in adults and children. In November 2012, Daiichi Sankyo submitted an application for Japan to manufacture and market Inavir® for the prevention of influenza infection. The Company has filed an Investigational New Drug application (“IND”) with the United States Food and Drug Administration (“FDA”) to develop laninamivir octanoate in the U.S., and in 2011 the Company was awarded a contract from the U.S. Office of Biomedical Advanced Research and Development Authority (“BARDA”) designed to provide up to $231.2 million in support of the development of and submission for a new drug application (“NDA”) of laninamivir octanoate for the treatment of influenza A and B infections in the United States.

Although several of the Company’s influenza products have been successfully developed and commercialized by other larger pharmaceutical companies under license agreements, the Company has not received regulatory approval for any product candidates it has developed independently, and does not have any sales, marketing or commercial capabilities. Therefore, it is possible that the Company may not successfully derive any significant product revenues or earnings from any of its existing or future development-stage product candidates.