Radiotherapy is employed in the treatment of over half of all cancer patients in an effort to kill cancer cells. Unfortunately, many patients incur damage to normal (non-cancerous) tissues in the path of the radiation beam or in areas surrounding the tumor. Additionally, tumors recur in approximately half the patients treated with curative intent. Minimizing normal tissue damage, while increasing the killing effect from radiotherapy on the tumor would improve treatment efficacy and patient quality of life. Therapies with these effects are termed Radiation Modulators and are comprised of two broad categories:
- Radioprotectors/radiomitigators are agents given before and/or after any form of radiation treatment or exposure to prevent or reduce damage to normal tissues.
- Radiosensitizers are agents intended to enhance tumor cell killing during radiation treatment while having a minimal effect on normal tissue.
While no such drug exists today, an ideal modulator for cancer treatment would both protect the normal tissues and enhance the killing effect of radiation on the tumor.
Radioprotectors and mitigators are also being developed as potential countermeasures against nuclear/radiological terrorism or accidents.
There is an urgent and unmet need for safe, effective radiation modulators.