A proposed $225 million acquisition is expected to bookend Santen Pharmaceutical Co. Ltd.'s portfolio of intraocular pressure (IOP) products, the company's head of R&D told Medical Device Daily. Santen, of Osaka, Japan, already has a robust portfolio of IOP drugs – primarily in the form of eye drops – available worldwide, said Naveed Shams, who also is the chief scientific officer at Santen. What is missing, he said, is a product designed to treat end-stage disease.