Accuray Receives FDA Clearance for New Dose Calculation Technique for Body Radiosurgery

Worldwide Availability of Monte Carlo Dose Calculation Software Announced at European Radiation Oncology Meeting in Barcelona

BARCELONA, Spain, Sept. 10 /PRNewswire-FirstCall/ -- Accuray Incorporated (Nasdaq: ARAY), a global leader in the field of radiosurgery, announced today that its Monte Carlo Dose Calculation algorithm has received 510(k) clearance from the U.S. Food and Drug Administration and is now commercially available worldwide. This announcement was made as part of the product's launch at the 9th Biennial European Society for Therapeutic Radiology and Oncology (ESTRO) meeting on Physics and Radiation Technology for Clinical Radiotherapy in Barcelona, Spain.

Treatment with radiation therapy or radiosurgery requires a linear accelerator to deliver one or more x-ray beams to a target. Each beam is made up of trillions of photons, and each photon follows an individual path to the target. Traditional dose calculation methods assume all photons take a single path and therefore use a single calculation to represent the dose delivered by all photons.

Monte Carlo methods are considered the gold standard of probabilistic statistics. The Monte Carlo dose calculation method takes the probability and potential interactions for each individual photon into account when it calculates the dose being delivered by a single photon. It then considers the probabilities for each of millions of photons to generate a dose calculation for the target and surrounding structures.

Previously, because of the repetition of algorithms and the large number of calculations involved, Monte Carlo dose calculations were time consuming to compute and therefore were difficult to employ in clinical settings. Now, by integrating various speed-up techniques, Accuray has developed a Monte Carlo dose calculation algorithm that can more quickly and precisely predict the dose of radiation that will be delivered to tumors.

"The clearance and commercial availability of Accuray's Monte Carlo Dose Calculation algorithm is a significant milestone in the use of radiosurgery to treat tumors anywhere in the body, particularly lung tumors" said Euan S. Thomson, Ph.D., president and CEO of Accuray. "We are extremely excited to be the first to market with a Monte Carlo dose calculation algorithm for photon beam radiation treatment that is capable of calculating the results within minutes. Now our customers will have access to the most state-of-the-art radiosurgery system with the most cutting-edge dose calculation algorithm."

The Monte Carlo dose calculation methodology is ideal for use in treating lung tumors, which are solid masses surrounded by air cavities, because it takes into account varying tissue densities. By integrating the Monte Carlo Dose Calculation algorithm with the CyberKnife(R) Robotic Radiosurgery System, Accuray offers clinicians one of the most advanced tools available today for treating lung cancer.

"Current dose calculation algorithms work well for treating most tumors because the surrounding tissue is relatively uniform, but assumptions had to be made within areas like the lungs and sinuses where tissue densities differ," said Charlie Ma, Ph.D., director of radiation physics at Fox Chase Cancer Center in Philadelphia, who helped develop this customized version of Monte Carlo dose calculation for the CyberKnife System. "Now Accuray's Monte Carlo Dose Calculation algorithm provides the most accurate physics-based model of radiation transfer available to date and the system is capable of computing complex dose distributions within minutes. This is a significant step forward in cancer treatment."

The Monte Carlo Dose Calculation capability will be available for purchase as a software upgrade for customers with the Multiplan(R) 2.0 Treatment Planning System and is scheduled to begin shipping toward the end of this calendar year. For customers who do not already have the MultiPlan 2.0 System, the Monte Carlo Dose Calculation feature will be available to them with the purchase of a MultiPlan 2.0 System. This new feature will also be available to customers who have previously signed Accuray's Diamond Elite Service Agreement. The Diamond Elite Service Agreement enables customers to choose the right upgrades to fit their clinical strategy. Unlike traditional industry service programs, Accuray's Diamond Elite Service Agreement maintains client investments with obsolescence protection, which ensures their systems' clinical capabilities remain at the forefront of technological advances.

"With Accuray's service program we've been able to upgrade our system with the latest technologies as soon they become available - keeping our CyberKnife System on the cutting edge," said Alan Beckman, M.D., Chief of Radiation Oncology at Central Baptist Hospital in Lexington, Ky. "Through the service agreement we look forward to acquiring the new Monte Carlo Dose Calculation feature in order to enhance our CyberKnife practice even further with this gold standard capability."

About the CyberKnife(R) Robotic Radiosurgery System

The CyberKnife Robotic Radiosurgery System is the world's only robotic radiosurgery system cleared by the FDA to treat tumors anywhere in the body non-invasively and with sub-millimeter accuracy. Using continual image guidance technology and computer controlled robotic mobility, the CyberKnife System automatically tracks, detects and corrects for tumor and patient movement in real-time throughout the treatment. This enables the CyberKnife System to deliver precise, high-dose radiation, minimizing damage to surrounding healthy tissue and eliminating the need for invasive head or body stabilization frames.

About Accuray

Accuray Incorporated (Nasdaq: ARAY), based in Sunnyvale, Calif., is a global leader in the field of radiosurgery dedicated to providing an improved quality of life and a non-surgical treatment option for those diagnosed with cancer. Accuray develops and markets the CyberKnife Robotic Radiosurgery System, which extends the benefits of radiosurgery to include extracranial tumors, including those in the spine, lung, prostate, liver and pancreas. To date, the CyberKnife System has been used to treat more than 35,000 patients worldwide and currently more than 100 systems have been installed in leading hospitals in the Americas, Europe and Asia. For more information, please visit www.accuray.com.

Safe Harbor Statement

The foregoing may contain certain forward-looking statements that involve risks and uncertainties, including uncertainties associated with the medical device industry. Except for the historical information contained herein, the matters set forth in this press release regarding procedure growth and market acceptance, clinical studies, regulatory review and approval, and commercialization of products are forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements speak only as of the date the statements are made and are based on information available at the time those statements are made and/or management's good faith belief as of that time with respect to future events. You should not put undue reliance on any forward- looking statements. Important factors that could cause actual performance and results to differ materially from the forward-looking statements we make include: market acceptance of products; competing products, the combination of our products with complementary technology; and other risks detailed from time to time under the heading "Risk Factors" in our report on Form 10-K for the fiscal year ended June 30, 2007 fiscal 2007 as may be updated from time to time by our other filings with the Securities and Exchange Commission. The Company's actual results of operations may differ significantly from those contemplated by such forward-looking statements as a result of these and other factors. We assume no obligation to update forward-looking statements to reflect actual performance or results, changes in assumptions or changes in other factors affecting forward-looking information, except to the extent required by applicable securities laws.

SOURCE Accuray Incorporated
09/10/2007
CONTACT: Susan Lehman of Rockpoint Public Relations, +1-510-832-6006,
susan@rockpointpr.com; or Stephanie Tomei, Accuray Public Relations Manager,
+1-408-789-4234, stomei@accuray.com
Web site: http://www.accuray.com