IsoRay Announces "Cesium-131 Brachytherapy for Salvage of Recurrent High Grade Glioma" Poster Presentation at 21st Annual Scientific Meeting of Society for Neuro-Oncology

RICHLAND, Wash., Nov. 29, 2016

Highlights of the presentation included:

• High grade gliomas (a type of brain cancer that includes glioblastoma multiforme) are among the most difficult-to-treat cancers, with the majority of these cancers recurring despite aggressive multi-modality therapy. Once these cancers have recurred in the brain, life expectancy is 3 to 6 months on average.
• In this series, 18 patients who had recurrences of high grade glioma following standard-of-care therapy (typically surgery, external beam radiation therapy and chemotherapy) were treated with surgical removal of the recurrent tumor and placement of the GammaTile™ radiation therapy system.
• The GammaTile™ system uses Cesium-131 radiation sources embedded in a collagen carrier. Using GammaTile™, very high doses of radiation are precisely delivered to targeted tissue – in this case the surgical margin that likely contains remnants of cancer cells following surgical removal of the tumor.
• In these 18 patients, the tumor had re-grown at the surgical site following standard-of-care treatment at a median of four months. This short time to recurrence despite multi-modality therapy highlights the vexing nature of these cancers.
• Following surgery plus GammaTile™ treatment, three patients (16%) experienced a re-growth of the tumor at the surgical site at the median time of analysis of approximately six months. In order to determine the median time to surgical site recurrence, 50% of the patients would be required to experience recurrence. However only 16% of the patients have had a surgical site recurrence at the time of analysis, suggesting that the median time to recurrence is greater than six months.

Dr. Youssef commented, "Seeing an improvement, although not yet statistically significant, in the freedom from tumor re-growth was particularly surprising in this group of patients, since the treatments available when these cancers recur, such as GammaTile™, are generally not as effective as the front line treatments. With 10 of these patients still living, the median time to recurrence may be extended even more. In addition, the complications we observed after the surgery plus GammaTile™ treatment were minimal."

"With only 16% of patients experiencing a surgical site recurrence at 6 month median follow-up, it's clear that the GammaTile™ approach extends the time to recurrence when compared to standard-of-care treatment in this group of patients, although the final time frame currently remains undefined," said Tom LaVoy, Chairman and CEO of IsoRay. "The advantages of using Cesium-131 brachytherapy products in the brain and other parts of the body are gaining momentum with the medical community, and are increasingly responsible for improving the lives of cancer patients."

About IsoRay, Inc.

IsoRay, Inc., through its subsidiary, IsoRay Medical, Inc. is the sole producer of Cesium-131 brachytherapy seeds, which are expanding brachytherapy options throughout the body. Learn more about this innovative Richland, Washington Company and explore the many benefits and uses of Cesium-131 by visiting www.isoray.com. Join us on Facebook/IsoRay. Follow us on Twitter @IsoRay.

Safe Harbor Statement