Hydroxychloroquine trial for COVID-19 fizzles out
NCT ID NCT04333654
First seen Jun 26, 2026 · Last updated Jun 26, 2026
Summary
This early-phase study tested whether hydroxychloroquine, a drug used for malaria and autoimmune diseases, could reduce the amount of virus in adults with mild COVID-19 not needing oxygen. Only 8 people took part before the trial was stopped early. The study was too small to draw any meaningful conclusions about the drug's effect.
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
Active substance
hydroxychloroquine (Plaquenil)
What this could lead to
If it had worked, this could have pointed toward a treatment to reduce the amount of virus in people with mild COVID-19.
What could go wrong
This was a very small, early-phase trial that was terminated early, so results are not reliable. Hydroxychloroquine has not been proven effective for COVID-19 and can have serious side effects.
Disclaimer
Read more
Show less
This is a summary of
the original study
.
Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
This is a summary of the original study . Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for CORONAVIRUS INFECTION are added.
By submitting, you agree to our Terms of use
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Show contact details
Enter your email to view the contact information for this study.
By submitting, you agree to our Terms of use
Locations
-
Investigational Site Number 0561001
Brussels, BE-1200, Belgium
-
Investigational Site Number 0561002
Lodelinsart, 6042, Belgium
-
Investigational Site Number 2501001
Bordeaux, 33076, France
-
Investigational Site Number 2501002
Paris, 75005, France
-
Investigational Site Number 5281001
Groningen, 9728 NZ, Netherlands
-
Investigational Site Number 5281002
Harderwijk, 3844 DG, Netherlands
-
Investigational Site Number 8400001
Boston, Massachusetts, 02115, United States