Pilot Study of Hydroxychloroquine for the Treatment of AIMSS

Aromatase Inhibitor (AI) therapy is highly effective for post-menopausal, estrogen receptor (ER) positive breast cancer, yet the clinical effectiveness of AI therapy is limited by noncompliance and early treatment discontinuation due to musculoskeletal side effects, which include joint pain, joint stiffness, bone pain, muscle weakness, and myalgias. Methods to improve compliance to AI therapy have the potential to increase survival. This study will look at hydroxychloroquine (HCQ), a disease-modifying antirheumatic drug (DMARD) with well-established anti-inflammatory and immunomodulatory properties. It is FDA-approved for the treatment of conditions characterized by chronic inflammatory joint pain similar to AIMSS. This single-arm, proof of concept study will look for an improvement in joint pain for patients undergoing standard of care treatment involving AI therapy.