Evaluation of Sustained Disease Control With Nipocalimab Versus Placebo in the Phase 3 Vivacity-MG3 Study.

BACKGROUND

Patients with generalized myasthenia gravis (gMG) frequently have variable and fluctuating symptoms. Treatments providing long-term, sustained disease control are essential for improving function and health-related quality of life.

METHODS

In the phase 3 Vivacity-MG3 study, nipocalimab improved clinical outcomes in adults with gMG when added to standard-of-care (SOC) therapy. These post hoc analyses further assessed the ability of nipocalimab to produce sustained responses over 24 weeks, using the following response categories for total score improvements in Myasthenia Gravis-Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG), respectively: Meaningful Clinical Improvement (MCI; ≥ 2- and ≥ 3-point), Substantial Improvement (SI; ≥ 3- and ≥ 4-point), Considerable Improvement (CIP; ≥ 4- and ≥ 5), Composite Response (CR; MG-ADL improvement ≥ 2-points plus QMG improvement ≥ 3-points), and Minimal Symptom Expression (MSE; MG-ADL 0 or 1).

RESULTS

Significantly higher percentages of nipocalimab-treated than placebo-treated participants achieved MG-ADL MCI, SI, and CIP, sustained for ≥ 12 consecutive weeks; achievement of these outcomes occurred as early as week 1 among nipocalimab-treated participants. Similar results were observed for QMG MCI, SI, and CIP. Significantly higher percentages of nipocalimab-treated participants achieved CR, sustained for ≥ 8 consecutive weeks versus placebo; the likelihood of achieving sustained CR for ≥ 8 weeks was higher with nipocalimab (odds ratio = 6.3). Nipocalimab-treated participants were 4-fold more likely to achieve MSE, sustained for ≥ 8 consecutive weeks versus placebo (p = 0.022). MSE and CR were achieved earlier among nipocalimab-treated participants.

CONCLUSIONS

Nipocalimab treatment improves gMG symptoms earlier than placebo and provides meaningful and long-term sustained disease control over 24 weeks among participants with gMG.