Old malaria drug tested to protect blood vessels in rare autoimmune disease

This study tested whether adding hydroxychloroquine to standard treatment could improve blood vessel function in people with antiphospholipid syndrome (APS), a condition that causes dangerous blood clots. In this small, completed Phase 2 trial, 25 participants were randomly assigned to receive either hydroxychloroquine or a placebo, in addition to their usual care. The main goal was to see if the drug could help blood vessels relax and function better, which might reduce the risk of future clotting problems.