Thirteen drug makers joined forces with governments and health organisations including the Bill and Melinda Gates Foundation to help control or eliminate 10 "neglected tropical diseases" by 2020.
With new and existing pledges, companies will donate an average of 1.4bn treatments a year over the decade. They are also speeding up research into the diseases by sharing access to expertise and compounds for the development of new medicines.
Astra and Glaxo are sharing compounds for fighting illnesses such as Chagas disease, which kills more than 10,000 people each year.
Sir Andrew Witty, Glaxo's chief executive, said: "Many companies and organisations have worked for decades to fight these horrific diseases. But no one company or organisation can do it alone. We pledge to work hand-in-hand to revolutionise the way we fight these diseases now and in the future."
David Brennan, Astra's chief executive, added that they were "delighted to be one of the partners in this innovative collaboration".