Merck & Co has unveiled plans to buy Inspire Pharmaceuticals for $430 million, giving it a stronger foothold in the ophthalmology arena.

The move will grant Merck access to Inspire's key product Azasite (azithromycin ophthalmic solution), which is approved in the US for the treatment of bacterial conjunctivitis in patients one year and older, as well as royalties from Allergan's Restasis for dry eye.

The US drug giant said it will launch a tender offer for all outstanding common stock of Inspire at $5.00 per share in cash, representing a 26% premium on the closing price on April 4.

There is strong support for the deal on both sides, as both groups' boards of directors have given their unanimous approval, and Inspire has recommended that its shareholders tender their shares pursuant to the tender offer. 

Private equity group Warburg Pincus has already agreed to tender all of its shares - representing around 28% of the outstanding stock - into the offer, the companies said.


According to Beverly Lybrand, senior vice president and general manager, neuroscience and ophthalmology at Merck, the move "combines the talented commercialisation organisation at Inspire with the excellent team already in place at Merck", strengthening its ophthalmology business and positioning the firm for future growth with an expanded portfolio.

And explaining his firm's interest in the deal, Adrian Adams, president and chief executive of Inspire, called Merck "the ideal partner" to enhance the long-term potential of its portfolio of ophthalmic assets.