mRNA intramuscular vaccination produces a robust IgG antibody response in advanced neuromuscular disease.

SARS-CoV-2 vaccines protect against symptomatic and severe COVID-19. The BNT162b2/Pfizer and mRNA-1273/Moderna vaccines represent new vaccine technology relying on administration of mRNA encoding SARS-CoV-2 viral spike protein encased in lipid nanoparticles. The vaccines are administered as two doses into muscle, which elicits a strong response, typically within 14 days after the second dose. Neuromuscular diseases are characterized by the progressive loss of muscle and are often treated with chronic glucocorticoid steroids, both of which may contribute to a blunted immune response to vaccination. Here, we measured IgG antibody content and neutralizing antibody response after mRNA COVID-19 vaccination in non-ambulatory neuromuscular disease patients. After two doses of mRNA COVID-19 vaccine, median anti-receptor binding domain IgG and percent surrogate viral neutralization in non-ambulatory neuromuscular disease samples were significantly elevated similar to healthy vaccinated controls. As in healthy controls, COVID-19 vaccines produce greater antibody levels compared to those with a history of outpatient COVID-19 infection. This data documents that non-ambulatory neuromuscular disease patients respond well to two doses of mRNA COVID-19 vaccine despite low muscle mass and even chronic steroid use.