Abstract
Objective Experiences with the antimalarial quinacrine for systemic lupus erythematosus (SLE) and cutaneous lupus erythematosus (CLE) remain underexplored. We evaluated and compared dermatologists' and rheumatologists' experiences with quinacrine in managing SLE and/or CLE.
Methods We sent a structured survey to 102 SLE specialists within the Systemic Lupus International Collaborating Clinics (SLICC) and the Canadian Network for Improved Outcomes in Systemic Lupus Erythematosus (CaNIOS), and 200 members of the Rheumatologic Dermatology Society (RDS). Participants responded to questions on self-reported quinacrine prescription history, perceived clinical benefit, reasons for drug discontinuation, and barriers to prescribing.
Results A total of 20 dermatologists from RDS and 40 SLICC and CaNIOS members responded to the survey. All RDS participants (100%) had previously prescribed quinacrine, compared to 17/40 (43%) of SLICC/CaNIOS participants. The majority of quinacrine prescribers (100% RDS, 12/17 [71%] SLICC/ CaNIOS) had prescribed quinacrine in combination with another antimalarial. Hydroxychloroquine (HCQ) or chloroquine (CQ) intolerance (65% RDS, 47% SLICC/CaNIOS) and HCQ/CQ-related retinal toxicity (50% RDS, 24% SLICC/CaNIOS) were other reasons for prescribing quinacrine. Clinical benefit was reported by 19/20 (95%) of RDS and 12/17 (71%) of SLICC/CaNIOS clinicians, and discontinuations were less frequent among RDS (5/20 [25%] reported none) compared to SLICC/CaNIOS (all 17 reported ≥ 1). Availability and cost of quinacrine were primary prescribing barriers.
Conclusion Surveyed dermatologists and rheumatologists differed in their experience with quinacrine for CLE and SLE, respectively. Availability remains a key barrier to prescribing, underscoring the need to address supply issues and conduct further research to optimize quinacrine use in SLE and CLE.
Plain Language Summary
Quinacrine is one of the oldest treatments for systemic and cutaneous lupus erythematosus. However, its use today is limited, especially due to supply issues. We surveyed dermatologists and rheumatologists who treat lupus to understand their experiences with quinacrine.
In this international survey, all dermatologists had used quinacrine to treat cutaneous lupus, whereas less than half of systemic lupus experts had used it. Most had used it in fewer than 10 patients over their careers. Common reasons for prescribing quinacrine were side effects from other antimalarials (such as hydroxychloroquine) including retinal damage, and lack of response to other drugs. Physicians found it useful to combine quinacrine and hydroxychloroquine to treat cutaneous lupus. In the future, most experts said they would consider prescribing quinacrine for cutaneous lupus that did not respond to other drugs. Conducting more studies, including clinical trials, and establishing a reliable supply could give patients more opportunities to use quinacrine.
