Men suffering from prostate cancer can be given an extra nine months to live due to the development of a vitamin D pill to fight the disease.

U.S. drug company Novacea, has produced a pill which delivers a concentrated dose of the vitamin, eliminating risks of side-effects from an overdose.

Reports are that if clinical trials of the drug - Asentar (DN-101) - are successful, the pill could be available by 2009.

The drug would be administered to patients in the advanced stage along with other chemotherapy drugs. Professor Nick James, a cancer expert at the University of Birmingham, said in the preliminary tests patients taking the drug lived for an average of nine months than those taking only Taxotere.

High levels of vitamin d

Asentar provides levels of Vitamin D 50 to 100 times higher than normal. Patients would take one tablet once a week with their weekly dose of Taxotere for three weeks out of every four.

Professor James noted, that Vitamin D is known to play a key role in the regulation of numerous tissues including the prostate and breast.

Research has shown that the rate of prostate cancer is higher in countries further away from the equator, where there is less exposure to sunlight.

In the U.K. prostate cancer is the second leading cause of cancer death in men. It kills one man every hour in the U.K.