AGBL3 and rheumatoid arthritis: Currently, a U.S. placebo-controlled study entitled StopRA (Strategy for the Prevention of Onset of Clinically-Apparent RA) is evaluating whether HCQ can prevent or delay the onset of RA in individuals pre-determined to be at high risk of developing disease (based on family history and anti-CCP3 positivity ≥ 2 times the upper limit of normal, regardless of whether arthralgia is present) (Koffeman et al., 2009).