Moving away from 3 drug therapy?

Matthew Shields has already done an excellent summary of the three most interesting presentations in "Antiviral therapy 1".

I will try to add a few points without doubling too much over the content.

Follow up of all small cohorts were to 24 weeks only.

The first presentation was on dolutegravir 50mg bd monotherapy in virologically suppressed treatment experienced individuals with healthy CD4 counts (many on atypical regimens including PI monotherapy) in a 33 patient "spur of the moment" pilot study. The authors explained 1 failure through extenuating psychosocial circumstances.

The second presentation from France was on dolutegravir 50mg once daily monotherapy in an older (mean 47, duration ART 17 years) virologically suppressed treatment experienced individuals (1/3 mono, 1/3 dual, 1/3 triple therapy). Three treatment failures were linked to resistance mutations in integrase but those identified were not classically for dolutegravir.

The third study was DTG+3TC in 20 treatment naive individuals and marked as sponsored by ViiV, who will fund a clinical trial soon in the area. Patients had viral loads less than 100,000 copies/ml and CD4 above 200. All patients had viral loads <400 copies by Week 3 and <50 by Week 8.

My conclusions were:

1. Follow up to 24 weeks was a significant limitation to these pilot studies. Further work is needed.

2. Dolutegravir resistance is certainly possible.

3. First line two drug dolutegravir containing therapy may certainly be a possibility, either with lamivudine or otherwise, but data is currently insufficient to support this.

4. Dolutegravir monotherapy could be considered in treatment experienced patients who have burnt out other options but there isn't enough to recommend switching for simplicity of regimen.

5. Early virological suppression does not necessarily translate to treatment efficacy.