Comparable viral decay with initial dolutegravir plus lamivudine versus dolutegravir-based triple therapy

J Antimicrob Chemother. 2019 Aug 1;74(8):2365-2369. doi: 10.1093/jac/dkz190.


Objectives: To expand understanding of the virological potency of initial dolutegravir plus lamivudine dual therapy (dolutegravir/lamivudine), we compared the viral decay seen in the pilot ACTG A5353 study with the decay observed with dolutegravir plus two NRTIs in the SPRING-1 and SINGLE studies, while also exploring the impact of baseline viral load (VL).

Methods: Change in VL from baseline was calculated for timepoints shared by A5353 (n = 120, including 37 participants with pretreatment VL >100000 copies/mL), SPRING-1 (n = 51) and SINGLE (n = 417). The 95% CIs of change from baseline were determined for each observed week, using the mean log10-transformed VL, and compared between the dolutegravir/lamivudine and triple therapy groups using the Wilcoxon Rank Sum test for non-inferiority (δ = 0.5). To assess the impact of baseline VL on viral decay, we examined a bi-exponential non-linear mixed-effect model.

Results: The mean VL change from baseline to week 24 was -2.9 log10 copies/mL for dolutegravir/lamivudine versus -3.0 log10 copies/mL for dolutegravir-based three-drug therapy (P < 0.001). In the decay model, baseline VL >100000 copies/mL was associated with a slower initial decay rate (d1). A faster initial decay rate was seen with dolutegravir/lamivudine, which was partially offset when baseline VL was >100000 copies/mL as indicated by a significant interaction between baseline VL and drug therapy group. The secondary decay rate (d2) was not significantly different from zero, with no significant associations.

Conclusions: Viral decay with dolutegravir/lamivudine was comparable to viral decay with dolutegravir-based triple therapy, even in individuals with higher pretreatment VL (>100000 copies/mL).

Publication types

  • Clinical Study
  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-HIV Agents / administration & dosage*
  • Antiretroviral Therapy, Highly Active / methods*
  • Clinical Studies as Topic
  • HIV Infections / drug therapy*
  • HIV Infections / virology
  • HIV-1 / isolation & purification*
  • Heterocyclic Compounds, 3-Ring / administration & dosage*
  • Humans
  • Lamivudine / administration & dosage*
  • Oxazines
  • Piperazines
  • Pyridones
  • Treatment Outcome
  • Viral Load*


  • Anti-HIV Agents
  • Heterocyclic Compounds, 3-Ring
  • Oxazines
  • Piperazines
  • Pyridones
  • Lamivudine
  • dolutegravir