Study of Afimetoran in Adults With Cutaneous Lupus Erythematosus

This study is evaluating whether afimetoran, an investigational oral medicine that blocks toll-like receptors 7 and 8 (TLR7/TLR8), can improve skin disease in adults with active cutaneous lupus erythematosus (CLE), with or without systemic lupus, whose disease has not responded to or who cannot tolerate antimalarial therapy. Participants are assigned by chance to receive afimetoran or a matching placebo capsule once daily for 24 weeks, in addition to their existing standard lupus care. Neither participants nor study staff know which treatment is given. The study is run in two stages under a single protocol. Stage 1 compares two doses of afimetoran with placebo to select the dose. Stage 2 compares the selected afimetoran dose with placebo to confirm efficacy and safety. After the 24-week placebo-controlled period, all participants receive afimetoran for a further 28 weeks, for a total of 52 weeks of treatment. The main measures of benefit are the change in the CLASI-A skin activity score and the proportion of participants achieving a 70% improvement in that score at Week 24.

Inclusion Criteria: 1. Adults aged ≥18 years (or ≥16 years where permitted). 2. Histologically confirmed active cutaneous lupus erythematosus (CLE) with or without systemic manifestations. 3. Active subacute and/or chronic cutaneous lupus erythematosus, including discoid lupus erythematosus. 4. Moderate to severe skin disease activity. 5. Refractory, intolerant, or inadequately controlled on antimalarial therapy. 6. Willing and able to comply with study requirements. 7. Agreement to protocol-specified contraception requirements Exclusion Criteria: 1. Severe lupus nephritis or severe neuropsychiatric SLE 2. Drug-induced lupus 3. Active or chronic clinically significant infections, including HIV, hepatitis B, hepatitis C, active tuberculosis, untreated latent tuberculosis, or uncontrolled congestive heart failure 4. Significant concurrent autoimmune disease other than lupus-related conditions permitted by the protocol 5. Active malignancy or recent history of certain cancers 6. Other dermatologic conditions that may interfere with study assessments 7. Recent use of prohibited medications or investigational therapies 8. Prior treatment with afimetoran or another TLR7/TLR8 antagonist 9. Clinically significant laboratory abnormalities or severe organ dysfunction 10. Pregnancy or breastfeeding