Evidence for earlier prescription of rituximab in adult generalized myasthenia gravis

At a time when new therapeutic families are emerging in autoimmune myasthenia, an “old” treatment (rituximab) could play a new role. Indicated until now in refractory forms of the disease, it has just been evaluated in recent generalised myasthenia (12 months or less) by the phase III clinical trial Rinomax, conducted in Sweden in 47 adults:

• 25 received an intravenous infusion of 500mg rituximab, 22 received a placeboLe placebo est un produit dont la présentation est identique à celle d’un médicament, mais qui ne contient pas de principe actif. Dans un essai clinique, un placebo est utilisé pour mesurer l’action réelle du médicament testé, en comparant les effets du médicament testé contenant le principe actif et ceux du placebo. infusion;
• 16 weeks later, 71% of participants in the rituximab group and 29% of those in the placebo group had an MGQ score of 4 or less on prednisone 10mg/day or less, without the need for additional treatment (primary endpoint of the trial);
• 4% of participants in the rituximab group and 36% of those in the placebo group required additional treatment (IVIG, other biotherapies, etc.) within 24 weeks after injection;
• all three hospitalizations due to myasthenia exacerbations occurred in the placebo group.

These results suggest that rituximab may be effective when started earlier and that a single, reduced dose is sufficient.

Efficacy and Safety of Rituximab for New-Onset Generalized Myasthenia Gravis: The RINOMAX Randomized Clinical Trial. Piehl F, Eriksson-Dufva A, Budzianowska A et al. JAMA Neurol. 2022 Sep 19:e222887.

 

Rituximab in Newly Diagnosed Generalized Myasthenia Gravis: A New Treatment Paradigm? Chuquilin M, Barohn R. JAMA Neurol. 2022 Sep 19.