For Release

Inc. Reports Third Quarter Results

Washington - IsoRay Inc. (AMEX: ISR) a medical isotope company focusing on the

treatment of prostate and other malignant disease through use of its proprietary

radioisotope technology, announced its financial results for the third quarter

of fiscal year 2009, ended March 31, 2009.

revenue for the quarter decreased by 23% to approximately $1,366,289 as compared

to approximately $1,783,642 in the third quarter of fiscal

2008. Fifty medical centers ordered the Company's Proxcelan

seeds in the third quarter of fiscal 2009 compared to the 57 centers that

ordered in the second quarter of fiscal 2008. Management believes

that the decline in sales revenue resulted primarily from decreased sales volume

and is partially attributable to a lower average invoice price due to the

expanded use of the Company's seeds in dual therapy cases which typically use

Company's net loss decreased 29% from approximately $2,091,640 in the quarter

ended March 31, 2008 to $1,482,648 in the quarter ended March 31,

Company had cash of approximately $5,163,920 and short-term investments of

approximately $480,005 as of March 31, 2009.

Babcock, IsoRay Chairman and CEO, commented "Although, the quarter's sales

results were disappointing, we significantly narrowed our net loss while

continuing to invest in new marketing and sales initiatives, such as the

February 18, 2009 exclusive distribution agreement with

BrachySciences. We continue to believe that we have the initiatives

and personnel in place to improve sales growth and experience future operating

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

Cesium-131 brachytherapy seed.

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

other isotopes commonly used for brachytherapy, which results in a substantially

faster delivery of therapeutic radiation, a theoretically improved radiation

delivery against aggressively replicating cancer(a), and

the potential for a reduced longevity of common brachytherapy side effects(b).

is currently used in the treatment of prostate cancer(c) and

ocular melanoma(d), among

other cancerous conditions.

is based in Richland, Washington. More information is available about IsoRay at

in this news release about IsoRay's future expectations, including: the

advantages of our Cesium-131 seed, future demand for IsoRay's existing and

planned products, IsoRay's manufacturing needs and capabilities, whether

IsoRay's sales and marketing strategy will result in improved sales, whether

IsoRay will be able to continue to reduce operating costs and increase revenue,

the impact of reimbursement rates for competing therapies on demand for IsoRay's

product, and all other statements in this release, other than historical facts,

are "forward-looking statements" within the meaning of the Private Securities

Litigation Reform Act of 1995 ("PSLRA"). This statement is included for the

express purpose of availing IsoRay, Inc. of the protections of the safe harbor

provisions of the PSLRA. It is important to note that actual results

and ultimate corporate actions could differ materially from those in such

forward-looking statements based on such factors as physician acceptance,

training and use of IsoRay's products, changing levels of demand for IsoRay's

current and proposed future products; whether later studies and protocols

support the findings of the initial studies, success of future research and

development activities, IsoRay's ability to successfully manufacture, market and

sell its products, IsoRay's ability to manufacture its products in sufficient

quantities to meet demand within required delivery time periods while meeting

its quality control standards, IsoRay's ability to enforce its intellectual

property rights, changes in reimbursement rates, changes in laws and regulations

applicable to our product, whether the exclusive distribution agreement with

BrachySciences results in sales, and other risks detailed from time to time in

IsoRay's reports filed with the SEC.

Inc. and Subsidiaries

Statements of Operations