Targeted Radiotherapeutics
Radiation therapy is the medical use of ionizing radiation to
treat cancer.
Traditional radiotherapy involves the use of focused external radiation beams that are aimed from several angles to intersect at the location of a tumor, providing a more concentrated dose of radiation at that site of disease than in the surrounding healthy tissue. Traditional radiation therapy is often used in combination with surgery, chemotherapy and/or hormone therapy. It is estimated that between 50–60% of cancer patients undergo radiation therapy during the course of their treatment. While effective for treating the primary tumor or local spread, external beam radiation may result in damage to the surrounding healthy tissue, and, importantly, is not appropriate when the cancer has metastasized to distant areas of the body.
The field of molecular medicine is facilitating the development of even more precise therapies through the creation of targeted radiotherapeutics. Molecular Insight is developing targeted therapeutic radiopharmaceuticals for the treatment of prostate cancer. These radiopharmaceuticals, administered systemically to a patient, consist of a homing portion of the molecule that seeks out and attaches to a cancer-restricted protein associated with the disease, enabling the delivery of the radioactive therapeutic portion of the molecule specifically to the diseased cancer cells thereby sparing the surrounding healthy tissue and organs. The ability to specifically deliver radiation to cancer cells anywhere in the body is a significant advance, allowing radiation to be applied to systemic disease.
Targeted therapeutic radiopharmaceuticals can be designed that are capable of delivering a variety of different radioisotopes--further enabling physicians to not only selectively target a tumor but to adjust the intensity of the radiation dose depending on the size and location of the tumor. Molecular Insight’s radiotherapeutic product candidate is 131I-MIP-1095.

