U.S. drug giant Pfizer, Inc., in cooperation with a leading research charity, will donate $66 million in drugs to help fight trachoma, the leading cause of preventable blindness, Reuters reports.

The disease affects the poorest people in the developing world where poor hygiene and lack of water abound. A two-year program developed by Pfizer and the Edna McConnell Clark Foundation in New York will treat sufferers in Morocco, Mali, Ghana, Tanzania and Vietnam.

According to World Heath Organization, more than 150 million people have the disease and about 10 percent of the world's population - 540 million - are at risk of developing it. Another 11 countries have been targeted as high-risk areas for the disease.

Pfizer introduced the drug Zithromax, which the company says is easier to administer and equally effective as treatments previously used.