Complex sentence: In 1975 Duke joined WHO as head of Filariasis infectious unit, his earlier research enabled the clinical trials of Ivermectin to go smoothly, this anti-parastic drug proved very effective against River Blindness and other diseases caused by parasitic worms.
Split into simpler sentences: In 1975 Duke joined WHO as head of Filariasis infectious unit, his earlier research enabling the clinical trials of Ivermectin to go smoothly. This anti-parastic drug proved very effective against River Blindness and other diseases caused by parasitic worms.