The GCAT Registry
The GCAT (Giant Cell Arteritis Tocilizumab) Registry was a post-marketing surveillance registry studying the effectiveness, safety and prescribing habits of tocilizumab for the treatment of GCA in the UK National Health Service. It was nested within the existing structure of the established UK GCA Consortium (Leeds; 05/Q1108/28) and UKIVAS (Oxford;10/H1102/77) studies. The GCAT Registry was supported by Roche Products Limited as an Investigator Initiated Study until its closure in June 2020 due to the COVID-19 pandemic.
Background to the GCAT Registry
Tocilizumab is now licensed in the US and EU for the prevention of relapses in giant cell arteritis (GCA) following the successful clinical trial GiACTA. However, because this is the first introduction of IL-6 pathway inhibition into clinical care of GCA, there remain important clinical questions regarding the effectiveness and safety of this therapy in routine clinical practice. Post-marketing surveillance is essential in order to provide precise and generalizable estimates of risks and benefits of this treatment. In particular, it is not known if tocilizumab affects the incidence of long-term complications of GCA, such as visual loss, large-vessel aneurysm or stenosis.
In the UK, a commissioning decision by the National Institute of Health and Care Excellence (NICE) was announced (on 18 April 2018), allowing the use of tocilizumab in GCA. This decision will be reviewed after a specified time-period (anticipated to be 2021) and is likely to be dependent on real-life clinical outcome data, including data relevant to health economic analyses such as resource use and health-related quality of life. Unique to the UK, is the stipulation that tocilizumab can be prescribed for no more than one year and only once for each patient. The main aim of the GCAT Registry was to collect such data by assessing the effectiveness and safety of tocilizumab in controlling refractory or relapsing GCA in patients who required escalation therapy to reach sustained remission. The primary objective was to determine the proportion of eligible patients who achieved sustained partial or complete remission 6 months after the start of tocilizumab.
On the 10th September 2018, the Scottish Medicines Consortium (SMC) completed its assessment of tocilizumab for the treatment of GCA – taking into account of views from a Patient and Clinician Engagement (PACE) meeting and the results of the GiACTA trial. They provided advice to the NHS Boards and Area Drug and Therapeutic Committees on its use in NHS Scotland. This document can be found here.