Effect of Applying Inclusion and Exclusion Criteria of Phase III Complement Inhibitor and FCRN Inhibitor Trials to Acetylcholine Receptor-positive Generalized Myasthenia Gravis Patients in Routine Clinical Care
Nakul Katyal1, Katherine Clifford2, Martavius Lovall2, Neelam Goyal3, Srikanth Muppidi3
1Neurology, University of Kentucky, 2Stanford Healthcare, 3Stanford University
Objective:
To analyze the eligibility of acetylcholine receptor antibody-positive generalized myasthenia gravis (AchR+ gMG) patients treated in routine care into the phase III clinical trial of newly approved complement and FCRN inhibitor therapies.
Background:
Complement and FCRN inhibitor therapies have been approved by FDA for AChR+ve gMG. Clinical trials leading to the approval had strict inclusion and exclusion criterias.
Design/Methods:
This retrospective study included AChR+ve gMG patients with documented myasthenia gravis activities of daily living (MG-ADL) scores, seen in outpatient clinics between January 2021 to June 2023. Clinical information including MG history, concomitant treatment(s) and MG-ADL score was analyzed at each clinic visit to determine the eligibility of patients into the clinical trials.
Results:
A total of 67 patients had a total of 330 visits between January 2021 and June 2023. 60 out 67 (89.5%) patients at 315 out of 330 (95%) clinic visits did not meet the eligibility criteria for the clinical trials. MG-ADL >5 was the single most frequent criterion not fulfilled, followed by IVIG use within the last 4 weeks of clinic visit. At 75 out of 330 (22.5%) clinic visits where MG-ADL score was >5, prior use of complement inhibitor medication and IVIG use within the last 4 weeks of clinic visit were the reasons for not meeting the eligibility criteria.
Conclusions:
The majority of AchR+ gMG patients treated in routine care would not have met clinical trials criteria for phase III complement inhibitor and FCRN inhibitor trials. Broader inclusion criteria would increase patient eligibility and contribute to a better generalizability of the results in clinical trials.