This is the eagerly anticipated large switch study for dolutegravir (DTG ) needed to round off the drug’s development and clinical applicability. The efficacy data was first presented at ICAAC in September with some focus here on secondary endpoints such as safety and satisfaction.
551 patients taking stable PI, INSTI and NNRTI based regimens were randomised to switch to ABC/3TC/DTG (n=277) or not (n=274). Switching to Triumeq was non-inferior to continuing ART, 85% vs 88%, difference -3.4% (CI95: -9.1%, 2.3%). No patients had protocol defined virologic failure and therefore no patients were evaluated for treatment-emergent resistance in either arm. In conclusion this large, robust open label switch study had great results in terms of safety, satisfaction and efficacy.
On Thursday ( from Antiretroviral Therapy Session 1 ) I posted some very interesting pilot studies looking at DTG monotherapy in maintenance or novel bicombos in naïve patients such as 3TC/DTG. These are studies which are beginning to answer some of the burning questions that we have have about the genetic barrier of DTG.
STRIIVING is not one of those studies
The background to this is SWITCHMRK. In this study patients on stable PI based regimens who were randomised to switch to TDF/FTC/RAL exhibited virological failure if they had fostered NRTI mutations in the past. Ever since this study switch studies have excluded patients at baseline who have had prior NRTI virological failure/resistance including the SPIRIT study (switch to TDF/FTC/RPV) and STRATEGY PI (switch toTDF/FTC/EVG/c). This study is no exception.
Therefore this study highlights an important point for clinicians considering switching patients it ABC/3TC/DTG. If the patient is on a stable PI based regimen one has to revise how they arrived there. In essence this robust switch study does not yet answer the question “Can I put my first line failures on ABC/3TC/DTG?” It may be possible in the future as we discern more about DTG genetic barrier.
The answer to this question will likely come from a second line study recruiting now where NNRTI failures are randomised to receive either ABC/3TC/DTG or DTG/LPV/r viewable here on the clinicaltrials.gov site:
This study is called DAWNING.