In the SWORD studies, the two-drug regimen showed comparable efficacy to three- or four-drug regimensin virologically suppressed patients. ViiV Healthcare, the global specialist HIV company majority-owned by GSK, with Pfizer Inc. and Shionogi Limited as shareholders, today announced detailed study results from its phase III programme evaluating the safety and efficacy of switching virologically suppressed patients from a three- or four-drug antiretroviral regimen to a two-drug regimen of dolutegravir and rilpivirine .