Novartis is selling the US rights to the overactive bladder treatment Enablex to Warner Chilcott in a deal worth around $420 million to the Swiss major.

The companies have been co-marketing Enablex (darifenacin) in the USA since October last year when Warner Chilcott acquired the pharmaceutical division of Procter & Gamble for $3.1 billion in cash. According to the terms of this latest agreement, Novartis will receive an upfront fee of $400 million and could pocket additional milestone payments of up to $20 million.

The Basel-based group is retaining the rights outside the USA to Enablex which was approved by the Food and Drug Administration in 2004 and launched in 2005. US sales last year reached $190 million.

Roger Boissonneault, Warner Chilcott's chief executive, said the deal "bolsters our franchise in the urology segment, provides us with greater control in promoting the product and demonstrates our ability to successfully add complementary assets to an already-strong product portfolio".

The deal is expected to close by the end of October, and Warner Chilcott, which has its headquarters in Ardee, Ireland, also announced that it has sold $500 million in senior notes, due 2018, to finance the transaction.