Intraop Medical Obtains Rights to Etanidazole

[August 2000]  Intraop Medical, Inc. announced that it has obtained the rights to market and manufacture the drug Etanidazole from Shire Pharmaceutical. Etanidazole is a radiation sensitizer---a pharmaceutical that enhances the effect of radiation on certain tumor cells. Radiation sensitizers are particularly effective in advanced and recurrent tumors which are hypoxic (oxygen deficient). Because of their hypoxia, these tumors typically require higher levels of radiation or chemotherapy to destroy them.

Previous studies have shown that Etanidazole should have an enhancement factor of 2 to 2.5. That means, for every unit of radiation delivered to normal tissues, the tumor will receive 2.5 units of radiation. Furthermore, during IORT, a large dose of sensitizer can be given simultaneously with a large dose of radiation, providing the ideal situation to achieve the maximum benefit from the sensitizer.

Etanidazole has successfully completed an IORT Phase I Study (1) under the direction of the Radiation Therapy Oncology Group (RTOG Study #89-06). During this study, the safety and timing of the drug delivery for IORT was determined.

Intraop Medical will sponsor a randomized Phase III Clinical trial under the auspices of the International Society of IORT to determine if the addition of Etanidazole during IORT is clinically more effective than IORT alone for advanced and recurrent rectal cancer. (See IORT/Clinical Trials on this Web site). If shown to be effective for colorectal cancer, its use will be extended to other IORT sites that have high components of hypoxic tumor.

(1) "RTOG #89-06: A Phase I Study to Evaluate Intraoperative Radiation Therapy and the Hypoxic Cell Sensitizer Etanidazole in Locally Advanced Malignancies", F. Halberg, et. al., Int. J. Radiation Oncology Biol. Physics, Vol. 28, No. 1, pp. 201-206, January, 1994