PHOENIX – Generalized myasthenia gravis patients had dramatically lower incidence of flares and crises after starting on the complement component 5 inhibitor eculizumab (Soliris), data from a real-world registry showed.
Hospitalization dropped threefold to 22.0 versus 72.1 events per 100 person-years in the previous 12 months while on standard of care therapy for acetylcholine receptor-positive generalized myasthenia gravis (AChR+ gMG), reported Rup Tandan, MD, of the University of Vermont Medical Center in Burlington.
The most serious admissions and those specifically related to the disease showed the biggest reductions, he reported in a poster presentation at the American Association of Neuromuscular & Electrodiagnostic Medicine meeting.
"These findings from clinical practice extend the evidence associating eculizumab initiation with clinically meaningful benefits in patients with AChR+ gMG," Tandan concluded.
Further breaking down the types of visits to the hospital comparing the standard of care period to the period while on eculizumab, his group showed:
- Myasthenia crises fell by 90%, from a rate of 11.2 to 1.7 per 100 person-years
- Myasthenia exacerbations dropped by 85.6%, from 34.2 to 3.4 per 100 person-years
- ICU admission also had an 85.6% reduction, from 18.0 to 2.6 per 100 patient-years
- Hospitalization for comorbidities saw a 56.6% reduction, from 9.9 to 4.3 per 100 person-years
- Other hospitalization events declined by about a quarter, from 16.4 to 12.4 per 100 person-years
"What we did here is to take patients with generalized myasthenia gravis who were not doing well on standard therapy, and we offered treatment to 182 of these individuals with eculizumab, and then we looked at how this treatment affected their visits to the emergency room and hospitalizations," Tandan told Ƶ.
In commenting on the study, Robert Pascuzzi, MD, of Indiana University in Indianapolis, noted that these were selected patients with "really bad myasthenia gravis" who had been treated with aggressive therapy.
"Once they started on eculizumab, their subsequent clinical course was markedly better, with far fewer hospitalization, far fewer near-death crises – and that is hugely important for people with myasthenia gravis and likely improves a patient's quality of life," he said in an interview.
Speculating on generalizability, Pascuzzi added, "I do think we would see similar results with the other newer agents available for treatment of myasthenia gravis."
In this U.S. and Canadian cohort study, the researchers determined the number of hospital visits in the 12 months prior to going on eculizumab and then followed the patients out for up to 3 years. They calculated person-years from individuals with complete hospitalization and emergency room data with treatment date and last visit date, with each person contributing 1 year of data before treatment initiation.
During the study, 76 of the 182 patients were hospitalized either before or after starting eculizumab, with a total of 239 hospitalizations. About 45% of women compared with 39% of men required hospitalization. About 40% of white, 67% of Hispanic, and 20% of Black patients were seen at the hospital or emergency departments.
Tandan said the next step in his work will be to do a cost-effectiveness analysis "to see if these drugs lead to dollars saved."
Pascuzzi acknowledged the importance of such studies: "These drugs are enormously expensive and can cost more than $20,000 a year, so it is important to show that there is cost saving. We do know that an extended stay in an intensive care unit can cost upwards of $100,000, so we think a cost-effectiveness study will show the benefit of eculizumab."
Disclosures
The study was sponsored by Alexion and AstraZeneca Rare Disease.
Tandan disclosed relationships with Apellis, Alexion, AstraZeneca, Mitsubishi Tanabe, Biogen, and Amylyx.
Pascuzzi disclosed no relationships with industry.
Primary Source
American Association of Neuromuscular & Electrodiagnostic Medicine
Tandan R, et al "Rates of myasthenic crises, exacerbation and healthcare resource utilization in eculizumab-treated patients from a generalized myasthenia gravis registry" AANEM 2023.