Pfizer has agreed to buy privately held biopharmaceutical company, Angiosyn, in a deal worth some $527 million dollars in up-front payments and royalties on future sales, the latter revealed this morning.

The deal expands Pfizer’s acquisition extends Pfizer’s research commitment in ophthalmology and gives the world’s largest pharmaceutical company access to Angiosyn’s novel angiostatic agent, which is being investigated as a possible treatment for ophthalmic diseases, such as macular degeneration, in which uncontrolled blood vessel growth can lead to decreased vision and blindness.

Under the terms of the deal, which is expected to close some time during the current quarter, Angiosyn would be merged into a wholly-owned subsidiary of Pfizer. Full payment is contingent on successful completion of commercial development for an ophthalmic indication and a second therapeutic area.

- Meanwhile, Pfizer has signed a separate deal with Rigel Pharmaceuticals that aims to research and develop inhaled products to treat allergic asthma and other respiratory diseases, such as chronic obstructive pulmonary disease.

Pfizer will pay Rigel will receive an undisclosed upfront cash payment, as well as milestone payments and royalties on any future product sales. It will also make an equity investment in Rigel and will be responsible for the worldwide development and commercialization of any resulting products. Financial terms of the agreement were not announced.