the combination du pont merck pharmaceuticals co. -lrb- estimated 1990 -rrb- sales $ 700 million sales staff 600 r & d spending $ 230 million r & d staff 1,500 from du pont world-wide rights coumadin -- for preventing heart attacks and strokes percodan -- -lrb- percocet -rrb- painkillers hespan -- plasma therapy ethmozine -- anti-arrhythmia from merck foreign rights or joint rights moduretic -- heart drug proscar -- experimental prostate treatment sinemet -- anti- parkinson 's treatment