Celsion Clarifies FDA Warning Letter.

Business Editors

COLUMBIA, Md.--(BUSINESS WIRE)--May 25, 2004

CELSION CORPORATION (AMEX:CLN) announced today that it has received a warning letter from the Food and Drug Administration (the FDA) regarding the Phase I and Phase II clinical trials of its Prolieve(TM) Thermodilatation system for the treatment of benign prostatic hyperplasia, or BPH. The FDA granted Premarketing Approval (PMA) to Celsion for the Prolieve system earlier this year, and the system currently is being marketed under a distribution agreement between Celsion and Boston Scientific Corporation.

The warning letter reflects matters that arose during the course of a pre-approval inspection conducted by the FDA's Baltimore regional office from December 9 through December 18, 2003 under a program designed to ensure that data and information contained in certain submissions to the Agency are scientifically valid and accurate and to ensure that human subjects are protected from undue hazard or risk during scientific investigations.

According to Carolyn Finkle, Celsion's Vice President-Regulatory, "We are committed to taking whatever actions are necessary to address fully the issues raised by the FDA. We are taking the FDA's letter very seriously and already have initiated short- and long-term corrective and compliance measures in response to the Agency's concerns. In addition, we have had two separate discussions with the Agency regarding both the actions that we have taken to date and those that we intend to take in the near future. Based on those discussions, we believe that we will be able to satisfy the Agency's concerns on a timetable that is achievable by us and acceptable to the FDA. So long as we succeed in fully addressing the issues raised by the FDA in a timely manner, and in light of the nature of the issues raised by the FDA, we do not anticipate that any further action by the FDA, including any actions that would affect the Prolieve PMA, will be warranted."

The warning letter addressed four general areas--monitoring, investigational agreements, provision of information to certain investigators, and FDA reporting--in connection with the Prolieve studies, both of which were completed by January 2002. The corrective and compliance measures initiated by the Company since receipt of the warning letter are in addition to certain corrective and compliance actions taken earlier by the Company to address observations made by the FDA inspector in connection with the December inspection. These earlier actions were detailed in a written submission by the Company to the FDA on December 23, 2003.

Anthony Deasey, Celsion's Executive Vice President and Chief Operating Officer said, "Celsion is a growing company, committed to operating in full compliance with applicable FDA regulations. While receipt of a warning letter is not generally considered a positive development, I expect that the actions that we are taking and the systems and procedures that we are implementing in response to the FDA's letter ultimately will make us a stronger, more effective company going forward."

About Celsion: Celsion Corporation, based in Columbia, Maryland, is a biotechnology company dedicated to the development and commercialization of treatment systems for cancer and other diseases using focused-heat energy, either administered alone, or in combination with other therapeutic devices, heat activated genes and heat activated drugs.

In January 2003, Celsion entered into a strategic alliance with Boston Scientific Corporation (NYSE:BSX) in which Boston Scientific will initially distribute Celsion's BPH product worldwide. Boston Scientific currently owns approximately 7% of Celsion's outstanding stock.

Celsion has research, license or commercialization agreements with leading institutions such as the National Institute of Health, Duke University Medical Center, Massachusetts Institute of Technology, Harbor UCLA Medical Center, Montefiore Medical Center and Memorial Sloan-Kettering Cancer Center in New York City, Roswell Park Cancer Institute in Buffalo, New York, and Duke University. For more information on Celsion, visit our website: www.celsion.com.

Celsion wishes to inform readers that forward-looking statements in this release are made pursuant to the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Readers are cautioned that such forward-looking statements involve risks and uncertainties including, without limitation, unforeseen changes in the course of research and development activities and in clinical trials by others; possible acquisitions of other technologies, assets or businesses; possible actions by customers, suppliers, competitors, regulatory authorities; and other risks detailed from time to time in the Company's periodic reports filed with the Securities and Exchange Commission.