P097 ‘Real-world’ Janus kinase inhibitor treatments in the UK-Irish A-STAR register: cohort profile and treatment outcomes
Authors: Carroll Rebecca , Gribaleva Elizaveta , Malek Rayka , Prieto-Merino David , Baden Manisha , Beattie Paula , Brown Sara , Burton Tim , Cameron Shona , Coker Bola , Cork Michael J , Hearn Ross , Ingram John R , Irvine Alan D , Johnston Graham A , Lambert Alice , Man Irene , Newell Louise , Ogg Graham , Patel Prakash , Wan Mandy , Warren Richard B , Woolf Richard , Reynolds Nick J , Ardern-Jones Michael R , Flohr Carsten 
Published: June 2024

Abstract
The Janus kinase inhibitors (JAKi), abrocitinib, baricitinib and upadacitinib, are novel systemic treatments for patients with moderate-to-severe atopic eczema, typically prescribed as a third-line systemic treatment options in UK practice. We sought to describe the treatment effectiveness and safety of these agents in the UK-Irish Atopic eczema Systemic TherApy Register (A-STAR), a prospective observational register of paediatric and adult patients receiving systemic treatment for atopic eczema. We analysed treatment effectiveness, focusing on Eczema Area and Severity Index (EASI). The minimum duration of treatment was 28 days and the follow-up time was a maximum of 12 months. We calculated the mean follow-up time until EASI 50, 75 and 90 were reached (≥ 50%, ≥ 75% and ≥ 90% improvement from baseline), or the patient terminated follow-up, without conducting formal comparisons between groups. Treatment safety was assessed by calculating incidence rates (IR) of adverse events (AEs) at follow-up. In total, 39 patients receiving abrocitinib, 21 on baricitinib, and 35 on upadacitinib were included. The mean time on treatment was 9.08 months (range 0.69–31.6) for abrocitinib, 8.07 (2.10–32.3) for baricitinib and 10.3 (0.46–27.7) for upadacitinib. Overall, 56% of patients were male, 77% were of White ethnicity, and the mean age was 32.5 years (SD 14.3). The mean baseline EASI was 20.4 (SD 13.8) for abrocitinib, 19.5 (SD 16.9) for baricitinib and 17.4 (SD 12.5) for upadacitinib. The percentage of patients who had had more than three past systemic treatments was 74% (n = 29) for abrocitinib, 76% (n = 16) for baricitinib, and 71% (n = 25) for upadacitinib. The mean follow-up to EASI 75 (in months) was 4.22 for abrocitinib, 4.78 for baricitinib and 4.24 for upadacitinib. EASI 50 and 90 followed similar trends (Table). Overall, 179 AEs were reported. Individually, for abrocitinib, baricitinib and upadacitinib, there were 68 AEs in 28 treatment cycles (IR 856 per 10 000 person-months), 30 AEs in 14 cycles (IR 1375) and 61 AEs in 23 cycles (IR 764), respectively. Serious AE data will also be presented. UK-Irish A-STAR register is a promising vehicle to collect real-world data on JAKi. All three treatments appear effective, even as third- and fourth-line therapy. Larger patient numbers are required for an adequately powered comparative analysis. A-STAR is funded through BADERL, a registered not-for-profit company within the British Association of Dermatologists. BADERL receives income from AbbVie, Eli Lilly and Pfizer for providing pharmacovigilance services. The A-STAR study protocol, study conduct and decisions concerning data analyses, interpretation and publication are made independently of any industry involvement.EASI 50EASI 75EASI 90TreatmentnMean monthsEventsaMean monthsEventsaMean monthsEventsaUpadacitinib253.2088%4.2464%5.1152%Abrocitinib303.2270%4.2253%5.4533%Baricitinib134.0054%4.7831%5.878%aPercentage of cohort achieving outcome.