Pharmaceutical giant Pfizer will soon acquire the late-stage small molecule anti-infectives business of AstraZeneca, a pharmaceutical and biologics company in London, as it expands its Essential Health portfolio.

The two entities entered into an agreement in which Pfizer will acquire the development and commercialization rights to the division, Pfizer said in a statement. Pfizer will pay $550 million initially for the company and then an additional deferred payment of $175 million in January 2019. The transaction is expected to close later this year.

One of AstraZeneca’s most popular pharmaceuticals, Zavicefta, addresses multi-drug resistant gram-negative infections.

Under the agreement, AstraZeneca is able to receive up to $250 million in milestone payments, up to $600 million in sales-related payments and royalties on Zavicefta and other products.

“As we continue to reshape our Essential Health portfolio, we are focusing on areas that further address global public health needs and that complement our core capabilities and experience in therapeutic areas, including anti-infectives,” said John Young, president of Pfizer Essential Health, in a statement. “The addition of AstraZeneca’s complementary small molecule anti-infectives portfolio will help expand patient access to these important medicines and enhance our global expertise and offerings in this increasingly important area of therapeutics, in addition to providing the opportunity for near-term revenue growth.”