UCB is beefing up its pipeline of epilepsy drugs with an NDA-ready therapy from Proximagen. The Belgian company has agreed to buy their nasal spray therapy USL261, designed as a rescue therapy for acute repetitive seizures, for $150 million in cash and another $220 million in sales and regulatory milestones.

There’s not a lot out there on this drug. UK-based Proximagen heralded a successful Phase III last year, without including any data from the pivotal. And it’s taken its web site down at least temporarily for renovations. Announcing the data last year, the biotech said that it would be filing an NDA before the end of the year, but UCB now says that they’ll be steering the application to regulators later this year.

Upsher-Smith Laboratories bought out Proximagen in 2012 in a $553 million deal. Then last year it sold its branded epilepsy therapy, Qudexy, and Proximagen became a subsidiary of a new holding company called Acova.

UCB notes their new therapy is a reworked nasal formulation of midazolam, which they plan to market to more than 150,000 epileptics who suffer from acute repetitive seizures, or ARS.

“There is a real and pressing need for effective and convenient rescue treatments in ARS that rapidly end ongoing seizures as well as those that prevent seizure reoccurrence,” explained Jean-Christophe Tellier, CEO of UCB. “Midazolam Nasal Spray has delivered strong Phase III results; our acquisition of this program, when approved, will expand and diversify the treatment choices we are able to provide to the epilepsy community, complementing our strong internal portfolio and building on our extensive knowledge, passion and expertise in the field of epilepsy.”