COMBAT-PsA

• Research type

  Research Study

• Full title

  COMBAT-PsA: Combination of Biologic and Anti-obesity Therapies in Psoriatic Arthritis

• IRAS ID

  362284

• Contact name

  Stefan Siebert

• Contact email

  stefan.siebert@glasgow.ac.uk

• Sponsor organisation

  NHS Greater Glasgow & Clyde

• Duration of Study in the UK

  4 years, 0 months, 0 days

• Research summary

  Obesity has a major negative impact on psoriatic arthritis (PsA). We want to better understand how inflammation is affected in people living with both psoriatic arthritis and obesity. In particular, we are interested in how weight loss influences the immune system in the key parts of the body involved in psoriatic arthritis. To explore this, we are using two medications that are already approved and used in the NHS:

  •Ixekizumab – used to treat inflammatory conditions such as psoriatic arthritis
  •Tirzepatide – used to support weight loss

  These medications will be used as research tools to help us examine how the body responds at a biological and immune level, particularly in relation to weight loss. By studying the effects of these treatments, we aim to better understand the underlying processes involved in psoriatic arthritis.

  Participants will be randomly (by chance) assigned to receive Ixekizumab on its own OR Tirzepatide on its own OR both medicines together. The purpose of this study is not to study or compare these medications directly, but to use them as tools to explore how the underlying immune system is affected.

  We will be recruiting 45 NHS patients aged 18-75 with psoriatic arthritis and obesity across 4 clinical research facilities in the UK (Glasgow, Birmingham, Coventry and Newcastle). Alongside taking the allocated medication(s), provided as part of the study, we will take blood samples and tissue samples (such as skin, fat tissue and the lining of the joints) at different time points to look at molecular changes in these key areas involved in psoriatic arthritis. Participants will also be asked to complete study questionnaires about how PsA affects their overall health and daily activities. Each participant will be involved in the study for a year.

• REC name

  London - Queen Square Research Ethics Committee

• REC reference

  25/LO/0864

• Date of REC Opinion

  9 Jan 2026

• REC opinion

  Further Information Favourable Opinion