The recently approved combination of dolutegravir and rilpivirine is effective for maintaining virological suppression in adults with HIV-1, according to results from the SWORD-1 and SWORD-2 noninferiority studies.

"The most interesting and significant finding in SWORD was that the dolutegravir and rilpivirine regimen achieved noninferior viral suppression (viral load <50 copies/mL) at 48 weeks compared with a three- or four-drug regimen,” Dr. Lesley P. Kahl “This happened in both the pooled and individual analyses of SWORD 1 and SWORD 2.”

Dr. Kahl et al. evaluated the efficacy and safety of dolutegravir-rilpivirine compared with continuation of current ART for 48 weeks in 1,028 adults infected with HIV-1. At the week 48 primary-endpoint analysis, 95% of patients in SWORD-1 and 94% of patients in SWORD-2 maintained viral suppression after switching to dolutegravir-rilpivirine, compared with 96% and 94%, respectively, who remained on their current ART, the researchers report in The Lancet

In the pooled analysis, 95% of participants in both treatment groups maintained viral loads lower than 50 copies/mL, thereby confirming the noninferiority of dolutegravir-rilpivirine. Patients switching to dolutegravir-rilpivirine had greater improvements in HIV Treatment Satisfaction Questionnaire total score and Symptom Bother Score, compared with patients continuing their current ART.

“The results from these studies change our understanding of how HIV can be managed,” Dr. Kahl said. “For more than 20 years we thought that three or more drugs were required to maintain virologic suppression, but the SWORD studies provide compelling data that suppression can be maintained with a two-drug regimen of dolutegravir and rilpivirine.”

Dr. Kahl added, “The U.S. FDA approved Juluca (dolutegravir and rilpivirine), as a complete regimen for the treatment of human immunodeficiency virus type 1 (HIV-1) infection in adults who are virologically suppressed (HIV-1 RNA less than 50 copies/mL) on a stable antiretroviral regimen for at least six months with no history of treatment failure and no known substitutions associated with resistance to the individual components of Juluca.”

Dr. Mark A. Boyd, who coauthored a linked editorial reported, "It is important that this study result isn’t seen as meaning that DTG+RPV can be used in people with viral replication – e.g., ART-naive people living with HIV (PLHIV) or people virologically failing their current ART regimen. More research is required in different PLHIV populations to reach that conclusion.”

“It’s also important that clinicians ensure that there has been no prior failure to agents that may confer cross resistance to either DTG or RPV (or that previous genotypic antiretroviral resistance test, GART, results don’t suggest baseline resistance to either of the 2 drugs),” Dr. Boyd said.

Dr. Jose M. Gatell who has also evaluated dolutegravir-based regimens said, "Maintenance treatment is a business for life, quite often for more than 20-40 years. The lower the number of drugs, the better is in terms of convenience, tolerance, and potential drug-drug interactions.

“Dual therapy is an option in virologically suppressed patients. Besides virologically suppressed patients, dual therapy may also become an option in antiretroviral-naive patients.”