Cypress Bioscience is to acquire Proprius Pharmaceuticals in a $75 million deal that will boost its product offering and justify its building of a sales force ahead of a potential launch for its fibromyalgia treatment milnacipran.

The agreement includes an upfront payment of $37.5 million in cash and an additional $37.5 million in potential milestone payments associated with the development of Proprius' two therapeutic candidates, one for pain and another for rheumatoid arthritis.

However the latter firm also specialises in rheumatoid arthritis prediction technology and MTX polyglutamates monitoring assays and it is Cypress’ intention to promote these products and milnacipran. Cypress and Forest Laboratories are co-developing that compound, a dual-reuptake inhibitor that has been marketed as an antidepressant, for the treatment of fibromyalgia, a disorder that mainly affects women and causes intense pain and stiffness, fatigue and depression.

The sale force that Cypress will put together for milnacipran will target rheumatologists and pain specialists, so getting hold of Proprius’ products and promoting them to the same people makes strategic sense. Milnacipran is currently under review by US regulators and Cypress expects to launch the drug later this year or early 2009, pending approval.

Jay Kranzler, Cypress’ chief executive, said that the acquisition “affords us a unique strategic opportunity, one that will leverage our future sales force while enhancing its access to these specialists”. He added that the firm is positioned to become a robust clinical and commercial organisation with a distinct, meaningful and complementary product portfolio”.