Isoray - Innovative Brachytherapy

A Decade of Data Shows the Value of Isoray’s Cesium-131 As Prostate Cancer Internal Radiation Therapy Treatment

Sep 18, 2019

Overall Ten-Year Biochemical Success Rate for Entire Group Was 96.2%
Largest and Longest Followed Series of Cesium-131 Treated Patients Reported to Date

RICHLAND, WASHINGTON – September 18, 2019 –A recent publication is drawing attention for its positive report on a study of the ten-year findings on the impact of Cesium-131 internal radiation therapy in treating a series of cancer patients. The peer reviewed publication, Long-term Biochemical Outcomes Using Cesium-131 in Prostate Brachytherapy, was recently made available on the website of BRACHYTHERAPY, an international multidisciplinary journal.

The publication reported on a study of a series of 571 patients who were treated with Cesium-131 prostate brachytherapy at the Chicago (IL) Prostate Cancer Center by radiation oncologist Dr. Brian J. Moran. The overall group was composed of 55% low risk, 36% intermediate risk, and 9% high risk localized prostate cancer patients as defined by NCCN (National Comprehensive Cancer Network) guidelines.

The majority of patients (83%) were treated with a Cesium-131 implant only, while the remainder were treated with external beam or hormone therapy — or both – added to the Cesium-131 implant in cases of higher risk disease. Long-term results were reported for this patient group at 5, 7, and 10 years*.  The overall biochemical success rate for the entire group of patients at ten years was 96.2%.

Based on the findings the authors noted, “Our results show that 5- and 10-year [biochemical] results were excellent…Our long-term results provide strong clinical impetus to continue prostate implantation with Cesium-131.” Lead author Dr. Moran said, “This is the largest and longest followed series of Cesium-131 treated patients reported to date. Given the notable biochemical outcomes, we view Cesium-131 as an excellent option for patients with localized prostate cancer, which is particularly noteworthy in light of the large component of intermediate risk patients in this series.”

Isoray CEO Lori Woods said this is the latest important development demonstrating the significance of Cesium-131. “We are very excited to see the findings of this study on the treatment of prostate cancer utilizing Cesium-131. The findings provide further evidence of the important option Cesium-131 provides patients and their doctors as a valuable therapeutic isotope. Our long-held confidence in our proprietary isotope is underscored by reports such as these issued from top quality investigators and institutions.”

Word of the publication comes as Isoray, Inc. is participating in the American Society for Radiation Oncology (ASTRO) annual meeting. Isoray representatives have been meeting with attendees at Booth #2612 providing a first-hand look at Blu Build. Blu Build is the latest advance in the application of Cesium-131 in treating prostate cancer. The real-time delivery system enables doctors to deliver a high radiation dose to the targeted prostate cancer and limits the impact on the surrounding areas compared to other treatment options. Attendees have also been meeting with company representatives to learn about recent developments regarding clinical applications of Cesium-131 in treating hard to treat cancers including brain, gynecological, lung, head and neck cancers.

*All estimates of biochemical success are based on Kaplan-Meier methodology using the Phoenix definition of biochemical failure (see Kuban, et al.  Comparison of biochemical failure definitions for permanent prostate brachytherapy. International Journal of Radiation Oncology Biology Physics 65(5):1487-93, 2006.)



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Investor Relations: Mark Levin (501) 255-1910

About Isoray

Isoray, Inc., through its subsidiary, Isoray Medical, Inc., is the sole producer of Cesium Blu brachytherapy seeds, which are expanding brachytherapy treatment options throughout the body. Learn more about this innovative Richland, Washington company and explore the many benefits and uses of Cesium Blu by visiting Join us on Facebook and follow us on Twitter.

Safe Harbor Statement

Statements in this news release about Isoray’s future expectations, including: efficacy of the biochemical success rate for 5 and 10 year results, the advantages of our products and their delivery systems, whether additional studies are released that support the conclusions of the study discussed in this news release, the perception by patients of quality of life outcomes compared to other treatment options, whether interest in and use of our products will increase or continue, the advantages of Blu Build, whether use of Cesium-131 in non-prostate applications will continue to increase revenue, 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 our products, our ability to successfully manufacture, market and sell our products, our ability to manufacture our products in sufficient quantities to meet demand within required delivery time periods while meeting our quality control standards, our ability to enforce our intellectual property rights, whether additional studies are released that support the conclusions of past studies, whether ongoing patient results with our products are favorable and in line with the conclusions of clinical studies and initial patient results, patient results achieved when our products are used for the treatment of cancers and malignant diseases, successful completion of future research and development activities, whether we, our distributors and our customers will successfully obtain and maintain all required regulatory approvals and licenses to market, sell and use our products in its various forms, continued compliance with ISO standards, the success of our sales and marketing efforts, changes in reimbursement rates, the procedures and regulatory requirements mandated by the FDA for 510(k) approval and reimbursement codes, changes in laws and regulations applicable to our products, the scheduling of physicians who either delay or do not schedule patients in periods anticipated, the use of competitors’ products in lieu of our products, less favorable reimbursement rates than anticipated for each of our products, and other risks detailed from time to time in Isoray’s reports filed with the SEC. Unless required to do so by law, we undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.