Note 13 - Technology Development and Licensing Agreements	3 Months Ended
Mar. 31, 2013
Licensing Transaction [Text Block]	Note 13. Technology Development and Licensing Agreements On January 18, 2013, we entered into a technology development contract with Zhejiang Hisun Pharmaceutical Co. Ltd. (Hisun), pursuant to which Hisun paid us a non-refundable research and development fee of $5 million to support our development of ThermoDox® in mainland China, Hong Kong and Macau. Following our announcement on January 31, 2013 that the HEAT study failed to meet its primary endpoint, Celsion and Hisun have agreed that the Technology Development Contract entered into on January 18, 2013 will remain in effect while the parties continue to collaborate and are evaluating the next steps in relation to ThermoDox, which include the sub-group analysis of patients in the Phase III HEAT Study for the hepatocellular carcinoma clinical indication and other activities to further the development of ThermoDox for the Greater China market. The $5.0 million received as a non-refundable payment from Hisun in the first quarter 2013 has been recorded to deferred revenue and will continue to be amortized over the 10 year term of the agreement, until such time as the parties find a mutually acceptable path forward on the development of Thermodox based on findings of the ongoing post-study analysis of the HEAT Study data. On May 7, 2012 the Company announced the signing of a long term commercial supply agreement with Hisun for the production of ThermoDox® in the China territory. In accordance with the terms of the agreement, Hisun will be responsible for providing all of the technical and regulatory support services, including the costs of all technical transfer, registration and bioequivalence studies, technical transfer costs, Celsion consultative support costs and the purchase of any necessary equipment and additional facility costs necessary to support capacity requirements for the manufacture of ThermoDox®. Celsion will repay Hisun for the aggregate amount of these development costs and fees commencing on the successful completion of three registration batches of ThermoDox®. Hisun is also obligated to certain performance requirements under the agreement. The agreement will initially be limited to a percentage of the production requirements of ThermoDox® in the China territory with Hisun retaining an option for additional global supply after local regulatory approval in the China territory. In addition, Hisun will collaborate with Celsion around the regulatory approval activities for ThermoDox® with the China State Food and Drug Administration (SFDA). As of March 31, 2013, the Company has incurred approximately $326,000 in costs to be reimbursed to Hisun. On December 5, 2008, we entered into a development, product supply and commercialization agreement with Yakult Honsha Co. (the Yakult Agreement) under which Yakult was granted the exclusive right to commercialize and market ThermoDox® for the Japanese market. We were paid a $2.5 million up-front licensing fee and may receive additional payments from Yakult upon receipt of marketing approval by the Japanese Ministry of Health, Labor and Welfare as well as upon the achievement of certain levels of sales and approval for new indications. Under the Yakult Agreement, we will receive double digit escalating royalties on the sale of ThermoDox® in Japan, when and if any such sales occur and we also will be the exclusive supplier of ThermoDox® to Yakult. Concurrent with a convertible preferred stock equity financing in January 2011, we amended the Yakult Agreement to provide for up to $4.0 million in accelerated partial payments to us on a drug approval milestone. The terms of the Yakult Agreement provided for the payment to us of $2.0 million upon the closing of the preferred equity financing. The second $2.0 million was conditioned upon the resumption of enrollment of Japanese patients in the Japan cohort of the HEAT study, which has not been resumed. In consideration of the $2.0 million accelerated milestone payment from Yakult, we have agreed to reduce future drug approval milestone payments by approximately twenty percent (20%). All other milestone payments are unaffected.

Note 13 - Technology Development and Licensing Agreements

3 Months Ended

Mar. 31, 2013

Note 13. Technology Development and Licensing Agreements

On January 18, 2013, we entered into a technology development contract with Zhejiang Hisun Pharmaceutical Co. Ltd. (Hisun), pursuant to which Hisun paid us a non-refundable research and development fee of $5 million to support our development of ThermoDox® in mainland China, Hong Kong and Macau. Following our announcement on January 31, 2013 that the HEAT study failed to meet its primary endpoint, Celsion and Hisun have agreed that the Technology Development Contract entered into on January 18, 2013 will remain in effect while the parties continue to collaborate and are evaluating the next steps in relation to ThermoDox, which include the sub-group analysis of patients in the Phase III HEAT Study for the hepatocellular carcinoma clinical indication and other activities to further the development of ThermoDox for the Greater China market. The $5.0 million received as a non-refundable payment from Hisun in the first quarter 2013 has been recorded to deferred revenue and will continue to be amortized over the 10 year term of the agreement, until such time as the parties find a mutually acceptable path forward on the development of Thermodox based on findings of the ongoing post-study analysis of the HEAT Study data.

On May 7, 2012 the Company announced the signing of a long term commercial supply agreement with Hisun for the production of ThermoDox® in the China territory. In accordance with the terms of the agreement, Hisun will be responsible for providing all of the technical and regulatory support services, including the costs of all technical transfer, registration and bioequivalence studies, technical transfer costs, Celsion consultative support costs and the purchase of any necessary equipment and additional facility costs necessary to support capacity requirements for the manufacture of ThermoDox®. Celsion will repay Hisun for the aggregate amount of these development costs and fees commencing on the successful completion of three registration batches of ThermoDox®. Hisun is also obligated to certain performance requirements under the agreement. The agreement will initially be limited to a percentage of the production requirements of ThermoDox® in the China territory with Hisun retaining an option for additional global supply after local regulatory approval in the China territory. In addition, Hisun will collaborate with Celsion around the regulatory approval activities for ThermoDox® with the China State Food and Drug Administration (SFDA). As of March 31, 2013, the Company has incurred approximately $326,000 in costs to be reimbursed to Hisun.

On December 5, 2008, we entered into a development, product supply and commercialization agreement with Yakult Honsha Co. (the Yakult Agreement) under which Yakult was granted the exclusive right to commercialize and market ThermoDox® for the Japanese market. We were paid a $2.5 million up-front licensing fee and may receive additional payments from Yakult upon receipt of marketing approval by the Japanese Ministry of Health, Labor and Welfare as well as upon the achievement of certain levels of sales and approval for new indications. Under the Yakult Agreement, we will receive double digit escalating royalties on the sale of ThermoDox® in Japan, when and if any such sales occur and we also will be the exclusive supplier of ThermoDox® to Yakult. Concurrent with a convertible preferred stock equity financing in January 2011, we amended the Yakult Agreement to provide for up to $4.0 million in accelerated partial payments to us on a drug approval milestone. The terms of the Yakult Agreement provided for the payment to us of $2.0 million upon the closing of the preferred equity financing. The second $2.0 million was conditioned upon the resumption of enrollment of Japanese patients in the Japan cohort of the HEAT study, which has not been resumed. In consideration of the $2.0 million accelerated milestone payment from Yakult, we have agreed to reduce future drug approval milestone payments by approximately twenty percent (20%). All other milestone payments are unaffected.