New class of cancer treatment tackles melanoma

2 Oct 2007

A new drug has been found to attack cancer by an innovative, unprecedented method. ‘STA-4783’, developed by Synta Pharmaceuticals Corp., USA, showed promise in treating advanced melanoma, slowing the progression of the disease and prolonging the lives of patients.

Its innovation came in the form of increasing the amount of certain chemicals such that cancer cells self destructed. These chemicals, known as reactive oxygen species (ROS), eg hydrogen peroxide, are present in all tissue cells, but at higher levels in cancer cells. When the ROS levels reach a certain threshold a cell will self-destruct. The new drug works by increasing ROS levels in all cells, but due to their higher levels only cancer cells reach the critical threshold.

The survival time without continued tumour growth was found to double while the overall average survival rate increased from 7.8 months to 12 months. Melanoma which has spread is widely recognised as very hard to treat, with current therapies being both limited and highly toxic. The average survival from diagnosis of advanced melanoma is about six months.

The study also indicated that STA-4783 might boost the efficiency of chemotherapy drugs that induce cell death because it appeared to lower the hurdle for activating that process.

Announcing the trial at this year’s European Cancer Conference in Barcelona, Dr Anthony Williams, vice president of Synta, said: “These results are encouraging not only because of the findings in themselves but also because there are so few treatment options for patients. We believe STA-4783 has the potential to improve survival with a manageable side effect profile. We also believe there is nothing unique about metastatic melanoma and that oxidative stress has the potential to be an entirely new class of cancer treatment that could have applications in other types of cancer.”

He also announced further trials which would take place by the end of the year investigating other types of cancer, yet to be decided, and estimated that the drug would be available in clinics within one year.