Varicella-zoster Virus

The primary objective of this study is to evaluate the vaccine efficacy, safety and immunogenicity of 2 injections (approximately 2 months apart) of ABO1108 in adults aged 40 years or above.

Immunocompromised individuals, such as patients with multiple sclerosis (MS) or diseases of the neuromyelitis optica spectrum (NMOSD) treated with an anti-CD20 monoclonal antibody, present an increased risk of shingles. The immunogenicity - and therefore the clinical effectiveness - of the recombinant vaccine against the varicella zoster virus based on glycoprotein E, recently recommended according to two-dose schedule two months apart in immunocompromised patients aged ≥ 18 years, could be significantly decreased when administered one month before and one month after the infusion of anti-CD20. We hypothesize that, in patients with MS or NMOSD treated with anti-CD20 administered every six months, a two-dose M0-M6 vaccination schedule consisting of deferring the second dose six months after the first infusion, that is, five months after the anti-CD20 infusion, could improve vaccine immunogenicity and, consequently, the effectiveness of the vaccine.