About The Study

This study examined if supplementation of a specially enhanced micronutrient preparation, compared to standard vitamins, can slow disease progression or delay the start of ARVs in asymptomatic adults currently not needing nor taking ARVs. Researchers examined the safety and effect of the supplement on participants’ health and well-being over two years. This was a three-year study recruiting 218 participants from The Ottawa Hospital and participating CTN sites.

Participants were randomly assigned to one of the two following equal groups:
• Group A (experimental arm): Participants received an oral micronutrient antioxidant preparation daily (K-PAX Ultra®)
• Group B (control arm): Participants received identical appearing standard multivitamins (Centrum-like)


The study enrolled and randomized a total of 171 participants, with 156 completing at least one study visit. Study researchers measured how well the trial participants were adhering to the treatment regimens using pill counts and two self-reported measurement scales. Treatment adherence was found to be high in the study group, over 80%. Preliminary analysis of micronutrient levels in blood samples showed that micronutrient deficiencies were common in study participants. Presented at CAHR 2017, there was no difference between the micronutrient group and the control group for CD4 count below 350 cells/μL, AIDS-defining illness, or start of ART.


Overall, CTN 328 showed that multivitamins are sufficient to address micronutrient deficiencies among people living with HIV but that there is no evidence to suggest that high-dose multivitamin-antioxidants are effective or necessary for the clinical management of HIV.

Additional Information

If you would like more information on this clinical study, please refer to clinicaltrials.gov.

Principal Investigators

Here’s who is leading this study.

Can’t find what you’re looking for? Email ctninfo@hivnet.ubc.ca.

Participating Sites

Here’s where this study is being conducted.