Drugmaker Gilead said it will allow cheap, generic versions to be sold in 120 poor countries with high HIV rates, mostly in Africa, Southeast Asia and the Caribbean.

A twice-yearly shot shows 100% effectiveness against HIV, but concerns arise over accessibility in Latin America and other regions.

The drug has been called a profound advancement in medicine but getting it to those who need it is a "missing piece in the puzzle," experts say. View on euronews

Another drugmaker, Viiv Healthcare, also left out most of Latin America when it allowed generics of its HIV prevention shot in about 90 countries. Sold as Apretude, the bi-monthly shots are about 80% to 90% effective in preventing HIV. They cost about $1,500 a year in middle-income countries, beyond what most can afford to pay.

It’s been called the closest the world has ever come to a vaccine against AIDS. The twice-yearly shot was 100% effective in preventing HIV infections in a study of women, and results published Wednesday show it worked nearly as well in men.