Evaluation of the efficacy of hydroxychloroquine in decreasing immune activation in asymptomatic HIV-infected patients

Can hydroxychloroquine be used to treat people with HIV?

What was this study about?

HCQ-01 was designed to find out whether hydroxychloroquine, if taken for 48 weeks would decrease immune activation caused by HIV infection. Previous studies (in the laboratory and also in clinical trials) had suggested that the drug might be of benefit on immune activation.

In HCQ-01, 83 people with early HIV infection who had a CD4 count greater than 400 cells and were not currently taking antiretroviral medication were randomised to take either Hydroxychloroquine (400mg/day) or placebo capsules for 48 weeks. Participants were enrolled from 10 sites in London and the south of England.

What difference did this study make?

The drug appeared to be well tolerated and did not cause any serious side effects. We found that it did not decrease immune activation. However, participants taking hydroxychloroquine had a small decrease in CD4 cell count and an increase in viral load (on average a doubling of their value at randomisation) during therapy. These changes were unexpected and the explanation for them is currently unclear.  However, the differences in CD4 count and viral load went away when participants stopped treatment. As a result of these changes, participants taking hydroxychloroquine also tended to start ART sooner than participants taking the placebo capsules.

Although it is disappointing that hydroxychloroquine does not appear to have a useful role in treating HIV infection (at least in participants who are not taking ART) the trial was successful in that it answered the clinical question it set out to address. The scientific information generated by the trial will be invaluable for designing future studies of treatments for immune activation and will also further our understanding of HIV disease.

Summary of the trial findings:

  • There was no difference between groups in CD8 T-cell activation, D-dimer or Il-6 nor other inflammatory cytokines, CD4 T-cell activation.
  • Hydroxychloroquine treatment caused a more rapid decline in CD4 count and shortened the time to ART initiation.
  • Hydroxychloroquine increased viral load.
  • These changes to VL and CD4 in the Hydroxychloroquine group went away after participants stopped treatment.
  • There was no excess of serious adverse events or eye problems in the hydroxychloroquine treated patients although there appeared to be an increased incidence of influenza symptoms. 

In conclusion hydroxychloroquine is not of benefit in the treatment of early chronic HIV infection as a strategy to delay the start of ART. Hydroxychloroquine does not ameliorate immune activation or inflammatory processes. Alternative approaches are needed to address HIV-induced immune activation and inflammation.

View trial results.

Type of study

Randomised trial

Contact details


Who funded the study?

The Wellcome Trust and the Medical Research Council.

When did it take place?

HCQ-01 ended in 2010 and study findings were published in 2012.

Where did it take place?

HCQ-01 took place in 10 hospitals in and around London and the South of England:

Brighton & Sussex University Hospitals NHS Trust (PI Dr Martin Fisher) | Chelsea and Westminster Hospital (PI Professor Brian Gazzard) | King's College Hospital (Dr Frank Post) | North Middlesex University Hospital (PI Dr Jonathan Ainsworth) | Royal Bournemouth Hospital (Dr Elbushra Herieka) | St Bartholomew's Hospital (PI Dr Chloe Orkin) | St Georges Hospital (PI Dr Mark Wansbrough-Jones) | St Mary's Hospital (PI Dr Alan Winston) | St Thomas’ Hospital (PI Dr Julia Fox) | University College London Medical School (PI Dr Ian Williams)

Who was included?

To join HCQ-01, participants had a CD4 cell count of at least 400, had never taken anti-HIV drugs, and had had no symptoms of HIV disease. Participants were randomly allocated to either start taking a hydroxychloroquine capsule once a day or to take a matching placebo capsule once a day. The duration of treatment in each patient was 48 weeks.