Brepocitinib (TYK2/JAK1 Inhibitor — Dermatomyositis)

MAXDOSE LEFT EMPTY: the label states a recommended dosage only and prints no maximum (the label mentions a 15 mg once daily trial arm as 'unapproved dosage'). VERBATIM (US label 2.2): 'The recommended dosage of LISRAYA is 30 mg once daily, administered orally with or without food.' LIMITATION OF USE (1): 'LISRAYA is not recommended for use in combination with other JAK inhibitors, other TYK2 inhibitors, or biologic DMARDs.' BEFORE STARTING (2.1): 'Prior to LISRAYA treatment initiation, consider performing the following: Active and latent tuberculosis (TB) infection evaluation: If positive, treat for TB prior to LISRAYA treatment. Viral hepatitis screening in accordance with clinical guidelines: LISRAYA is not recommended in patients with active hepatitis B or hepatitis C. A complete blood count: Avoid LISRAYA in patients with an absolute lymphocyte count less than 500 cells/mm3, absolute neutrophil count less than 1,000 cells/mm3, or hemoglobin level less than 8 g/dL. Baseline hepatic and renal function tests: LISRAYA is not recommended in patients with severe hepatic or severe renal impairment. Pregnancy Status: Verify the pregnancy status of females of reproductive potential prior to treatment. Update immunizations according to current immunization guidelines.' INTERRUPTION (2.3): 'If a patient develops a serious infection, including serious opportunistic infection, interrupt LISRAYA treatment until the infection resolves or is adequately treated.' Laboratory-based interruption (Table 1): interrupt if ANC is less than 1,000 cells/mm3, if ALC is less than 500 cells/mm3, or if Hb is less than 8 g/dL - treatment may be restarted once the value returns above the threshold; interrupt if drug-induced liver injury is suspected, until this diagnosis is excluded. SMOKING: exposure of brepocitinib is lower in current smokers, so effectiveness may be reduced (7.1). IMMUNIZATIONS: avoid use with live vaccines (5.10). AGE: no overall differences in effectiveness between patients 65 years and older and younger adults, but older adults experienced higher rates of serious adverse events in Trial DM (8.5). PAEDIATRIC: 'The safety and effectiveness of LISRAYA have not been established in pediatric patients' - no paediatric dose. No UK SPC for brepocitinib is listed on eMC — this dose is from US prescribing information (LISRAYA) and must be verified against UK practice.