NEW YORK (AP) -- Eye-drug maker Alcon said Monday it will buy Swiss biotechnology company ESBATech AG in a deal worth up to $589 million.

Alcon said it will pay $150 million in cash, with milestone payments of up to $439 million if ESBATech drug candidates advance through clinical development. ESBATech is a development-stage company with no products on the market, but is working on treatments for inflammatory eye diseases, as well as age-related macular degeneration, diabetic macular edema, glaucoma, and dry eye.

ESBATech shareholders will retain the rights to its non-ophthalmic drugs. The shareholders will spin off those rights into a separate company. Both companies are Swiss; Alcon is based in Huenenberg, while ESBATech is headquartered in Zurich.

In afternoon trading, Alcon shares lost 76 cents to $134.43.