Pfizer, a global research-based pharmaceutical company, has agreed to acquire NextWave Pharmaceuticals, a privately-held, specialty pharmaceutical company focused on attention deficit/hyperactivity disorder (ADHD) and related central nervous system (CNS) disorders.

Pfizer had previously entered into an option and merger agreement with NextWave during the second quarter 2012 and made an option payment of $20 million. Pfizer is exercising the option to acquire NextWave and will make a payment to of $255 million to NextWave's shareholders at the closing of the transaction. NextWave's shareholders are eligible to receive additional payments of up to $425 million based on certain sales milestones.

Through the acquisition Pfizer will gain Quillivant XR (methylphenidate hydrochloride), an extended-release oral suspension and the first once-daily liquid medication approved in the U.S. for the treatment of ADHD.

"This agreement demonstrates our focused expansion of the Established Products U.S. brands business to offer a diverse portfolio of high-quality medicines that meet patients' needs," said Albert Bourla, president and general manager in Pfizer's Established Products Business Unit. "By combining the advantages of Quillivant XR with Pfizer's commercialization expertise, we will be able to provide ADHD patients and their caregivers a new treatment option."

The transaction is expected to close during the fourth-quarter 2012, subject to regulatory approval in the U.S., and other customary closing conditions.