Note 1 - Company Overview	12 Months Ended
Jun. 30, 2014
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 its corporate headquarters are located in Alpharetta, Georgia. The Company is currently focused on developing oral, small molecule antiviral compounds to treat a number of respiratory-related infections. The most advanced clinical-stage program is laninamivir octanoate, a long-acting neuraminidase inhibitor (“NI”) that the Company is developing for the treatment of influenza A and B. On August 1, 2014, the Company reported top-line safety and efficacy results from a randomized, double-blind, placebo-controlled, parallel-arm Phase 2 clinical trial comparing the safety and efficacy of a 40 mg and 80 mg dose of laninamivir octanoate to placebo. As compared to placebo, neither the 40 mg nor the 80 mg cohort achieved a statistically significant reduction in the median time to alleviation of influenza symptoms, the primary endpoint, as measured by the Flu-iiQ patient-recorded outcome questionnaire. Certain important secondary endpoints, including quantitative viral shedding, and secondary bacterial infections, as well as the time to alleviation of influenza symptoms for a number of subcomponents, did achieve statistically significant results for laninamivir octanoate treated cohorts compared to placebo. The Company has not received the full data set from this trial and plans to assess this additional safety and efficacy data from this trial when received. The Company is also developing BTA-798, also known as vapendavir, which is in Phase 2 for the treatment of human rhinovirus (“HRV”) infections in patients with moderate to severe asthma. Biota has successfully completed two Phase 2 trials of vapendavir to date and recently completed additional Phase 1 bioavailability and drug-drug interaction studies of vapendavir in healthy volunteers. In addition to these Phase 2 clinical-stage development programs, the Company is also developing orally bioavailable F and non-F protein compounds for the treatment of respiratory syncytial (“RSV”) infections in children, the elderly and immune-compromised patients. The Company is currently conducting IND-enabling studies with BTA-C585, the lead compound from our F-protein inhibitor program. In March 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 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 U.S. On April 23, 2014, the Company was notified by the U.S. Department of Health and Human Services (HHS) office of the Assistant Secretary for Preparedness and Response (ASPR) and BARDA that pending a decision regarding the outcome of an In-Process Review (IPR) of the Company’s contract for the development of laninamivir octanoate, ASPR/BARDA had issued a Stop-Work Order notifying the Company to discontinue work on a number of activities that would no longer be reimbursed under the contract. On May 7, 2014, and based upon the results of the IPR, HHS/ASPR/BARDA notified the Company of its decision to terminate the contract for the convenience of the U.S. Government. The Company continues to work with ASPR/BARDA to close out this contract, which involves completing several clinical trials, finalizing invoices and billings, determining the nature and extent of any equitable adjustments, and negotiating a final termination settlement. Although several of the Company’s influenza product candidates have been successfully developed and commercialized to-date by other larger pharmaceutical companies under collaboration, license or commercialization agreements with the Company, Biota has not independently developed or received regulatory approval for any product candidate, and the Company does not currently have any sales, marketing or commercial capabilities. Therefore, it is possible that the Company may not successfully derive any significant product revenues from any product candidates that it is developing now, or may develop in the future. The Company expects to incur losses for the foreseeable future as it intends to support the clinical and preclinical development of its product candidates. Also, due to the recent termination of its contract with BARDA, the Company anticipates that its revenue from service and cost of revenue will decline substantially in the future as compared to recent levels. The Company plans to continue to finance its operations with (i) existing cash, cash equivalents and long-term investments, (ii) proceeds from existing or potential future royalty-bearing licenses or collaborative research and development arrangements, (iii) future equity and/or debt financings, or (iv) other financing arrangements. The Company’s ability to continue to support its operations is dependent, in the near-term, upon managing its cash resources, receiving reimbursements it receives from BARDA related to the close-out of its recently terminated contract, continuing to receive royalty revenue under existing licenses, entering into future collaboration, license or commercialization agreements, the successful development of its product candidates, executing future financings and ultimately, upon the approval of its products for sale and achieving positive cash flows from operations on a consistent basis. There can be no assurance that additional capital or funds will be available on terms acceptable to the Company, if at all, that the Company will be able to enter into collaboration, license or commercialization agreements in the future, or that the Company will ever generate significant product revenue and become operationally profitable on a consistent basis.

Note 1 - Company Overview

12 Months Ended

Jun. 30, 2014

(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 its corporate headquarters are located in Alpharetta, Georgia.

The Company is currently focused on developing oral, small molecule antiviral compounds to treat a number of respiratory-related infections. The most advanced clinical-stage program is laninamivir octanoate, a long-acting neuraminidase inhibitor (“NI”) that the Company is developing for the treatment of influenza A and B. On August 1, 2014, the Company reported top-line safety and efficacy results from a randomized, double-blind, placebo-controlled, parallel-arm Phase 2 clinical trial comparing the safety and efficacy of a 40 mg and 80 mg dose of laninamivir octanoate to placebo. As compared to placebo, neither the 40 mg nor the 80 mg cohort achieved a statistically significant reduction in the median time to alleviation of influenza symptoms, the primary endpoint, as measured by the Flu-iiQ patient-recorded outcome questionnaire. Certain important secondary endpoints, including quantitative viral shedding, and secondary bacterial infections, as well as the time to alleviation of influenza symptoms for a number of subcomponents, did achieve statistically significant results for laninamivir octanoate treated cohorts compared to placebo. The Company has not received the full data set from this trial and plans to assess this additional safety and efficacy data from this trial when received.

The Company is also developing BTA-798, also known as vapendavir, which is in Phase 2 for the treatment of human rhinovirus (“HRV”) infections in patients with moderate to severe asthma. Biota has successfully completed two Phase 2 trials of vapendavir to date and recently completed additional Phase 1 bioavailability and drug-drug interaction studies of vapendavir in healthy volunteers.

In addition to these Phase 2 clinical-stage development programs, the Company is also developing orally bioavailable F and non-F protein compounds for the treatment of respiratory syncytial (“RSV”) infections in children, the elderly and immune-compromised patients. The Company is currently conducting IND-enabling studies with BTA-C585, the lead compound from our F-protein inhibitor program.

In March 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 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 U.S. On April 23, 2014, the Company was notified by the U.S. Department of Health and Human Services (HHS) office of the Assistant Secretary for Preparedness and Response (ASPR) and BARDA that pending a decision regarding the outcome of an In-Process Review (IPR) of the Company’s contract for the development of laninamivir octanoate, ASPR/BARDA had issued a Stop-Work Order notifying the Company to discontinue work on a number of activities that would no longer be reimbursed under the contract. On May 7, 2014, and based upon the results of the IPR, HHS/ASPR/BARDA notified the Company of its decision to terminate the contract for the convenience of the U.S. Government. The Company continues to work with ASPR/BARDA to close out this contract, which involves completing several clinical trials, finalizing invoices and billings, determining the nature and extent of any equitable adjustments, and negotiating a final termination settlement.

Although several of the Company’s influenza product candidates have been successfully developed and commercialized to-date by other larger pharmaceutical companies under collaboration, license or commercialization agreements with the Company, Biota has not independently developed or received regulatory approval for any product candidate, and the Company does not currently have any sales, marketing or commercial capabilities. Therefore, it is possible that the Company may not successfully derive any significant product revenues from any product candidates that it is developing now, or may develop in the future. The Company expects to incur losses for the foreseeable future as it intends to support the clinical and preclinical development of its product candidates. Also, due to the recent termination of its contract with BARDA, the Company anticipates that its revenue from service and cost of revenue will decline substantially in the future as compared to recent levels.

The Company plans to continue to finance its operations with (i) existing cash, cash equivalents and long-term investments, (ii) proceeds from existing or potential future royalty-bearing licenses or collaborative research and development arrangements, (iii) future equity and/or debt financings, or (iv) other financing arrangements. The Company’s ability to continue to support its operations is dependent, in the near-term, upon managing its cash resources, receiving reimbursements it receives from BARDA related to the close-out of its recently terminated contract, continuing to receive royalty revenue under existing licenses, entering into future collaboration, license or commercialization agreements, the successful development of its product candidates, executing future financings and ultimately, upon the approval of its products for sale and achieving positive cash flows from operations on a consistent basis. There can be no assurance that additional capital or funds will be available on terms acceptable to the Company, if at all, that the Company will be able to enter into collaboration, license or commercialization agreements in the future, or that the Company will ever generate significant product revenue and become operationally profitable on a consistent basis.