Both regimens that you've listed are very potent and generally speaking, very well tolerated. There is considerable debate over which regimen is the best for persons with HIV, the first regimen (TDF/3TC/EFV) has been very well studied in the Gilead 903 clinical trial, the later regimen, Combivir/EFV, has long been the industry standard and has one of the best clinical trials datasets.
Recent pharmacological studies with tenofovir demonstrate that it matters little if the medication is taken with or without food- this means that you can take the Viread/Epivir/Sustiva regimen all together, probably at bedtime.
So, an all once-a-day or twice-a-day? This is a tough question to answer categorically. Both strategies have merits and limitations. Since the bulk of the literature is supportive of the Combivir/efavirenz combo, I'd be ignorant not to state this would be my first, off the shelf, recommendation. However, the GS903 study makes a compelling case for the once-daily, tenofovir-based regimen. For persons at risk of missed doses on a twice daily regimen, the study provides more than ample rationale for using this regimen. It is, however, only a single study, and I'd like to see independent confirmation of the results. Essential here is the idea that treatments should be individualized to the needs of individual persons, and not to assume that what goes for the majority might go for a single person-- so we need to listen to the concerns and requirements of individual patients while making these decisions.
The key issue for all of us is the confidence (and reproducibility) in the dataset for particular treatment regimens- short term studies should only yield short term confidence. So, while we are looking for long-term safety and durability in treatment, we should insist upon long-term clinical studies.
Thanks for reading. BY
