Centre of Evidence Based Dermatology

The Treatment of Hidradenitis Suppurativa Evaluation Study (THESEUS)

The THESEUS team includes people with hidradenitis suppurativa, dermatologists, GPs, surgeons and research experts.

Hidradenitis suppurativa is a long term, painful skin condition that affects approximately 1% of adults. It involves boils in areas such as the armpits and groins. The THESEUS study was developed to inform the design of future hidradenitis suppurativa trials and to help understand how hidradenitis suppurativa treatments are currently used. The study was developed with the support of the UK Dermatology Clinical Trials Network 

Cardiff-University-logo-for-website THESEUS was collaborative study being led by the Centre for Trials Research at Cardiff University.

Full details of study and results
(NIHR HTA report)

Key information

What did THESEUS involve?

THESEUS investigated five treatments: two medicines (doxycycline, clindamycin & rifampicin), two types of surgery (deroofing and excision), and laser treatment.  Further details about what each of these treatment choices entails can be found in the treatment decision grid.

The choice of treatment was decided by the participant and their doctor, and depended upon what treatment is available locally and severity of disease.

For further details, please see the patient information leaflet.

Who took part in the study?

Participants were

  • 18 years of age or older
  • Had a diagnosis of active hidradenitis suppurativa not controlled by current treatment.
Where did the study take place?

 Broomfield Hospital
 Forth Valley
 Guys and St Thomas
 Stoke Mandeville 


Who funded the study?
The research was funded by the UK Government, through the National Institute of Health Research Health Technology Assessment (NIHR HTA) programme.



 Research Priorities in the Management of Hidradenitis Suppurativa 
Leighton P, Howells L, Bates J, Gibbons A, Cannings-John R, Collier F, Evans J, Harris C, Hood K, Howes R, Riaz M, Rodrigues J, Stanton H, Thomas-Jones E, Thomas K, Ingram JR. Br J Dermatol. 2023 May 18:ljad152. doi: 10.1093/bjd/ljad152. Online ahead of print.

Treatment of Hidradenitis Suppurativa Evaluation Study (THESEUS): a prospective cohort study
John R Ingram, Janine Bates, Rebecca Cannings-John, Fiona Collier, Judith Evans, Angela Gibbons, Ceri Harris, Laura Howells, Kerenza Hood, Rachel Howes, Paul Leighton, Muhammad Riaz, Jeremy Rodrigues, Helen Stanton, Kim S Thomas, Emma Thomas-Jones, British Journal of Dermatology, 2023;, ljad388,

Treatment of Hidradenitis Suppurativa Evaluation Study (THESEUS): protocol for a prospective cohort studyBates J, Stanton H, Cannings-John R, Thomas KS, Leighton P, Howells LM, Rodrigues J, Howes R, Collier F, Harris C, Gibbons A, Thomas-Jones E, Hood K, Ingram JR. BMJ Open. 2022 Apr 21;12(4):e060815. doi: 10.1136/bmjopen-2022-060815.

The Surgical Management of Hidradenitis Suppurativa in the United Kingdom: A National Survey of Care Pathways Informing the Theseus Study.
Howes, R., J. R. Ingram, K. S. Thomas, F. Collier, and J. N. Rodrigues.J Plast Reconstr Aesthet Surg. 2021.

Primary Care Management of Hidradenitis Suppurativa: A Cross-Sectional Survey of Uk Gps.
Collier, F., R. Howes, J. Rodrigues, K. S. Thomas, P. Leighton, and J. R. Ingram.  BJGP Open. 5, no. 5, 2021.

Thematic Synthesis of the Experiences of People with Hidradenitis Suppurativa: A Systematic Review. Howells, L., N. Lancaster, M. McPhee, C. Bundy, J. R. Ingram, P. Leighton, K. Henaghan-Sykes, and K. S. Thomas. Br J Dermatol. 185, no. 5  921-34, 2021.

Population-based Clinical Practice Research Datalink studyusing algorithm modelling to identify the true burden of hidradenitis suppurativa
J.R. Ingram et al. British Journal of Dermatology (2018) 

A core domain set for hidradenitis suppurativa trial outcomes: an international Delphi process
L. Thorlacius and J.R. Ingram et al. British Journal of Dermatology (2018) 

Interventions for hidradenitis suppurativa: a Cochrane systematic review incorporating GRADE assessment of evidence quality
J.R. Ingram et al. British Journal of Dermatology  (2016) 

The Hidradenitis Suppurativa Priority Setting Partnership
J.R. Ingram et al. British Journal of Dermatology (2014)  

This study is funded by the National Institute for Health Research (NIHR) [Health Technology Assessment Programme (HTA Project: 17/98/01)]. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.

Centre of Evidence Based Dermatology

The University of Nottingham
Applied Health Research Building
University Park, Nottingham

telephone: +44 (0) 115 84 68631
email: cebd@nottingham.ac.uk