Document resource
Introduction The ADAPT trial showed that IV efargartigmod, an Fc Receptor antagonist was effective in treating generalised MG (gMG). Efartigimod was available in the UK under the Early Access to Medicine Scheme from May 2022 to Dec 2024 with over 100 patients treated to date. Subcutaneous (SC) preparations of efartigimod have been available in the UK since March 2024Aim To describe the efficacy and tolerability of SC efgartigmodMethods A retrospective review of a prospectively maintained database of all patients treated with efgartigimod at the NHNNResults 26 patients at the NHNN were initiated on IV efgartigmod treatment, 8 stopped treatment due to lack of efficacy. Of the remaining 16, 15 switched to SC efgartigimod when it became available. Six subsequently reverted to IV treatment due to lack of efficacy7 patients were started de novo on SC treatment and all have remained on it10 patient had injection site reactions usually in the first cycle. These tended not to reoccur and did not result in treatment discontinuation.Subcutaneous efgartigmod reduced IgG levels by 66% from baseline, this is comparable to IV efartigmod.Conclusion SC efartigmod is well tolerated in the majority of patients but a proportion of patients find IV efgartigimod more effective.aravindhan.baheerathan1@nhs.net