Targeted biologic therapies have transformed outcomes for individuals with psoriasis, a common immune-mediated inflammatory skin disease. The widespread use of these highly effective treatments has led to a growing number of individuals with clear or nearly clear skin remaining on continuous, long-term treatment. Personalised strategies to minimise drug exposure may sustain long-term disease control while reducing treatment burden, associated risks and healthcare costs. This study aims to evaluate the feasibility of a definitive pragmatic effectiveness trial of two personalised dose minimisation strategies compared with continuous treatment (standard care) in adults with well-controlled psoriasis receiving the exemplar biologic risankizumab.

This is a multicentre, assessor-blind, parallel group, open-label randomised controlled feasibility trial in the UK, evaluating two personalised biologic dose minimisation strategies for psoriasis. 90 adults with both physician-assessed and patient-assessed clear or nearly clear skin on risankizumab monotherapy for ≥12 months will be randomised in a 1:1:1 ratio to (1) patient-led ‘as-needed’ treatment, where risankizumab is administered at the first sign of self-assessed psoriasis recurrence, (2) therapeutic drug monitoring-guided treatment, with personalised dosing intervals determined using a pharmacokinetic model or (3) continuous treatment as per standard care, for 12 months. Participants will be invited to submit self-reported outcomes and self-taken photographs every 3 months using a bespoke remote monitoring system (mySkin app) and will attend an in-person assessment at 12 months. They may also request additional patient-initiated follow-up appointments during the trial if needed. The primary outcome is the practicality and acceptability of the two personalised biologic dose minimisation strategies, assessed as a composite measure including recruitment and retention rates, adherence to the assigned strategies and acceptability to both patients and clinicians. The feasibility of collecting healthcare cost and resource utilisation data will also be evaluated to inform a future cost-effectiveness analysis. A nested qualitative study, involving semistructured interviews with patients and clinicians, will explore perspectives on the personalised biologic dose minimisation strategies. These findings will inform the design of a future definitive trial.

This study received ethical approval from the Seasonal Research Ethics Committee (reference 24/LO/0089). Results will be disseminated through scientific conferences, peer-reviewed publications and patient/public engagement events. Lay summaries and infographics will be codeveloped with patient partners to ensure the findings are accessible for the wider public.

ISRCTN17922845.

Palmoplantar pustulosis (PPP) is a rare, debilitating inflammatory skin disease involving painful pustules on the palms and soles. Janus kinase (JAK) inhibitors target pathways relevant to PPP disease biology but also confer a risk of major adverse cardiovascular events and malignancy in certain ‘at risk’ individuals; this includes those with PPP given prevalent smoking and cardiovascular risk factors in the PPP population. The feasibility of JAK inhibitor therapy for PPP requires assessment prior to a randomised controlled trial evaluation of drug efficacy and safety for this indication.

The ‘Janus kinase inhibitors in palmoplantar pustulosis: a mixed-methods feasibility’ trial is an open-label, single-centre, single-arm, mixed-methods feasibility trial of JAK inhibition in PPP (REC reference: 24/NE/0147; ISRCTN61751241). Participants (n=20) will receive 8 weeks of treatment with the JAK inhibitor upadacitinib (‘Rinvoq’, 30 mg, once daily). Qualitative semistructured interviews (up to n=40) will be undertaken with trial participants, trial decliners and healthcare professionals. The primary outcome will be a composite assessment of feasibility across three domains: recruitment, adherence and acceptability, using a mixed-methods analysis approach. Secondary objectives include the identification of trial recruitment optimisation strategies, using the ‘Quintet Recruitment Intervention’, and the generation of an indication of effect size on disease severity (measured using the Palmoplantar Pustulosis Psoriasis Area and Severity Index) to inform future sample size calculations. Historic placebo control data from the Anakinra for Pustular Psoriasis: Response in a Controlled Trial (National Institute of Health and Social Care reference: 13/50/17; Research Ethics Commitee reference: 16/LO/0436) will be used as the effect size comparator. Study recruitment will be undertaken over a 24-month period, commencing in November 2024.

This study has been approved by the Newcastle North Tyneside 2 Research Ethics Committee, 24/NE/0132. Our findings will inform the feasibility of a future adequately powered RCT evaluating the efficacy of JAK inhibitor therapy in PPP.

ISRCTN61751241.