OA31 Real life experience of tocilizumab treatment for giant cell arteritis
Authors: Hutton Lisa M M 
Published: April 2023

Abstract

Background/Aims
Giant cell arteritis (GCA) has been revolutionised by fast track pathways that ensure early secure diagnosis. The GiACTA study provided evidence for the beneficial role of tocilizumab in the treatment of GCA and encouraged us all to reconsider the role of corticosteroids. These data relate to real life experience of the use of tocilizumab, including current status of patients after completing the initial year of treatment. In Scotland, tocilizumab was initially used for patients with relapsing disease or steroid complications. However, since 2018, the Scottish Medicines Consortium has supported use from disease onset and it has become increasingly common to consider adding at diagnosis.

Methods
The case notes of 23 patients treated with tocilizumab were reviewed back to 2017. Patient demographics were collated including whether cranial (C) or large vessel vasculitis (LVV) variant. The diagnosis of GCA had to be confirmed by biopsy or imaging with GCA rheumatology clinic review. Any patients who discontinued tocilizumab prior to completing one year had the reason recorded. Duration on tocilizumab was intended to be one year. Data were reviewed to capture outcomes after treatment was withdrawn.

Results
2 patients with non-relapsing disease discontinued tocilizumab within the first month due to early relative neutropenia (1.4). 5 of 21 patients who completed treatment have since had additional tocilizumab treatment. 1 patient with particularly severe relapsing disease and steroid complications remains on long term tapered tocilizumab monotherapy without attempt to stop (C and LVV). 4 patients (LVV=C) flared within 1-9 months (median 6 months) and resumed with steroids and subsequent tapers; all had commenced for relapsing disease. 1 patient (C), commenced on tocilizumab at diagnosis, opted for MTX when flared. 15 remaining patients are on no steroid, methotrexate or tocilizumab and are free of disease activity as yet, but undergoing monitoring for flare (12C 3 LVV variant).

Conclusion
Tocilizumab is effective, limits steroid exposure and is well-tolerated by patients. The most common reason for discontinuing tocilizumab was relative neutropenia (neutrophils 1-1.4). The majority of patients discontinued tocilizumab and have not yet flared off all treatment. Cranial variant was less associated with relapse after tocilizumab treatment versus LVV. New diagnoses appear less prone to relapse off tocilizumab than patients already known to have relapsing disease prior to using tocilizumab. Patients discontinuing tocilizumab benefit from ongoing monitoring to recognise the early stages of returning disease; this would need to be provided for at least one year. Patients discontinuing treatment, their GPs and carers need advice on routes to escalate concerns about returning symptoms. Fast track services need to provide a flare service in addition to a diagnosis pathway if there is to be safety, confidence and expert support for this patient group and primary care colleagues.
Disclosure
L.M.M. Hutton: Other; 2022 Roche educational grant to attend BSR.