The study, “Eculizumab improves fatigue in refractory generalized myasthenia gravis,” was published in Quality of Life Research.
Myasthenia gravis (MG) is an autoimmune disease caused by the abnormal production of antibodies against acetylcholine receptors necessary for muscle contraction. This leads to muscle weakness, lack of muscle endurance and extreme fatigue.
None of the current assessment tools to determine disease severity, including the patient-reported MG Activities of Daily Living (MG-ADL) scale, the 15-item MG Quality of Life (MG-QOL15) scale, and the physician-completed Quantitative MG (QMG) assessment of muscle strength, assesses the impact of fatigue on MG.
“Perceived fatigue (a feeling of tiredness, lack of energy, and difficulty concentrating) … is also an important clinical issue for these patients and may be distinct from muscle weakness and fatigability,” the researchers said.
The Quality of Life in Neurological Disorders (Neuro-QOL) Fatigue subscale is a 19-item self-assessment that incorporates “sensations ranging from tiredness to an overwhelming, debilitating, and sustained sense of exhaustion that decrease one’s capacity for physical, functional, social, and mental activities.” A shorter version of this scale has recently been validated in MG patients.
Soliris is a complement inhibitor that blocks signals from the immune system’s complement pathway thought to be involved in the formation of harmful autoantibodies in MG. Recent findings from the 26-week, randomized, double-blind, placebo-controlled Phase 3 REGAIN study (NCT01997229) and its 52-week open-label extension (NCT02301624) showed clinically meaningful improvements in patients with generalized MG.
In this study, researchers set out to investigate the effects of Soliris on perceived fatigue in a group of patients with generalized MG who participated in REGAIN using the Neuro-QOL scale.
A total of 125 patients with generalized MG were randomly assigned to be treated with either Soliris (62) or a placebo (63). All were scored with the MG-ADL, QMG, MG-QOL15 and Neuro-QOL Fatigue scales at week 26 of REGAIN.
Results showed that at week 26, patients treated with Soliris had a significant improvement in Neuro-QOL Fatigue scores compared to those treated with a placebo. These findings were consistent with MG-ADL, QMG, and MG-QOL15 scores that had been previously reported in REGAIN.
Correlation analysis confirmed that Neuro-QOL Fatigue scores were strongly correlated with MG-QOL15, MG-ADL, and QMG scores for patients treated with Soliris during REGAIN. Conversely, for patients treated with a placebo, score correlations were weaker.
Improvements in Neuro-QOL Fatigue scores in patients treated with Soliris were maintained over the course of the 52-week open-label extension of REGAIN.
“Our findings suggest that the Neuro-QOL Fatigue subscale may be used to assess the clinical impact of perceived fatigue and the effect of therapeutic interventions in patients with [generalized MG], [and] contribute to the consistency and totality of the data demonstrating that eculizumab lowers the clinical burden in [these] patients,” the scientists concluded.