Brachytherapy: An Initial Report.

Inc. ANNOUNCES MAJOR PUBLIC FINANCING

WA - IsoRay, Inc. ("IsoRay") (OTCBB Symbol: ISRY), the medical

technology company focusing on innovative treatments for solid cancer tumors

using its proprietary Cesium-131 brachytherapy seeds, announced today that

has closed a $16,522,000 equity financing led by Punk, Ziegel & Company, and

Maxim Group LLC on March 22, 2007.

transaction, IsoRay issued 4,130,500 registered shares of its common stock

$4.00 per share and also issued warrants to purchase 826,100 shares of its

common stock (excluding warrants issued to the placement agents, which have

180 day lock up) at an exercise price of $5.00 per share to various

institutional investors. If all warrants are exercised, IsoRay would receive

additional $4,130,500. The shares and warrants were sold pursuant to the

Company's registration statement on Form S-3 declared effective by the SEC on

proceeds from this offering are to be used to expand IsoRay's sales and

marketing, invest in plant and equipment, inclusive of manufacturing

technologies, which are expected to lower the company's production costs and

could be used to expand the application of medical isotopes beyond the prostate

market," said Roger Girard, CEO and Chairman of IsoRay.

press release does not constitute an offer to sell or the solicitation of a

offer to buy the shares of common stock or any other securities, nor will there

be a sale of the shares of common stock or any other securities in any state

jurisdiction in which such offer, solicitation or sale would be unlawful prior

to the registration or qualification under the securities laws of any such

shares of common stock and warrants may only be offered by means of a

prospectus. Copies of the final prospectus supplement and accompanying base

prospectus can be obtained from IsoRay, Inc., 350 Hills St., Suite 106,

Inc., through its subsidiary, IsoRay Medical, Inc., is the sole producer of

Cesium-131 brachytherapy seed, used to treat prostate and other cancers. The

Cesium-131 seed offers a significantly shorter half-life than the two other

isotopes commonly used for brachytherapy, which results in a substantially

faster delivery of therapeutic radiation, lower probability of cancer cell

survival and reduction of the longevity of common brachytherapy side effects.

[1] [2] IsoRay is based in Richland, Washington. More information is available

about IsoRay at www.isoray.com.

Armpilia CI, Dale RG, Coles IP, et al. The Determination of Radiobiologically

Optimized Half-lives for Radionuclides Used in Permanent Brachytherapy Implants.

Int. J. Radiation Oncology Biol. Phys. 2003; 55 (2): 378-385.

Prestidge B.R., Bice W.S., Jurkovic I., et al. Cesium-131 Permanent Prostate

Brachytherapy: An Initial Report. Int. J. Radiation Oncology Biol. Phys. 2005;

press release includes statements that may constitute forward-looking statements

within the meaning of the Private Securities Litigation Reform Act of 1995.

forward-looking statements are subject to a variety of known and unknown risks,

uncertainties, and other factors that are difficult to predict and many of

are beyond management's control. Factors that can affect future results are

discussed in the documents filed by IsoRay from time to time with the Securities

and Exchange Commission. IsoRay undertakes no obligation to update or revise

forward-looking statement to reflect new information or events.

Schatzmair, Director of Investor Relations

Bartlett, The Bartlett Group Public Relations