Soliris® is a late complement inhibitor approved by the US Food and Drug Administration (FDA) for the treatment of adult patients who have refractory, generalized myasthenia gravis (MG) that is positive for anti-acetylcholine receptor antibodies (anti-AChR-Abs). Soliris is also FDA-approved for the treatment of paroxysmal nocturnal hemoglobinuria to reduce hemolysis and in atypical hemolytic uremic syndrome to inhibit complement-mediated thrombotic microangiopathy.1

Soliris is available in a single-dose vial containing 300 mg/30 mL for intravenous administration.1

Dosing for Generalized Myasthenia Gravis

The recommended dose for patients who have generalized MG with anti-AChR-Abs is 900 mg weekly for the first 4 weeks, followed by 1200 mg for the fifth dose 1 week later, then 1200 mg every 2 weeks thereafter. The dose needs to be adjusted for patients undergoing supplemental plasma exchange (PLEX) therapy in the following manner1

  • If the patient’s last dose was 300 mg, a supplemental dose of 300 mg must be given with each PLEX session within 60 minutes after the treatment. 
  • If the patient’s last dose was 600 mg or higher, a supplemental dose of 600 mg must be given with each PLEX session within 60 minutes after the treatment. 
Soliris (eculizumab) for NMOSD
Credit: Getty Images


The efficacy of eculizumab was determined in a randomized placebo-controlled trial in which 62 patients who had generalized MG with anti-AChR-Abs received eculizumab and 63 received placebo. A greater improvement in clinical responsiveness, defined as a 3-point decrease in the Quantitative Myasthenia Gravis (QMG) total score and a 5-point decrease in the Myasthenia Gravis Activities of Daily Living (MG-ADL) score at week 26, was observed in the patients in the eculizumab group. The mean decrease in the MG-ADL score from baseline to week 26 among patients in the treatment arm was -4.2 points, compared with -2.3 points in the placebo group, a statistically significant difference  (P=0.006). Additionally, the mean reduction in the MG-ADL score in participants in the treatment arm was -4.6 points, compared with -1.6 points in the placebo group (P=0.001). Data suggest that clinical responsiveness appears by week 12 of treatment.1

Access the Soliris monograph page at MPR for full prescribing information.


Soliris limits the ability of the immune system to combat infection with Neisseria and other encapsulated bacteria. It should not be used in patients with serious, unresolved Neisseria meningitidis infection or those who are not currently vaccinated against N meningitidis. Immunization with meningococcal vaccines at least 2 weeks before administration of the first dose is recommended. In unvaccinated patients, Soliris should be withheld unless the risks of delaying Soliris treatment outweigh the risks of developing a meningococcal infection.1

Other bacteria that may cause serious infections include Streptococcus pneumoniae and Haemophilus influenzae. Infusion reactions including anaphylaxis are rare but possible with Soliris. Use should be discontinued if any signs of cardiorespiratory compromise develop.1

Common, non-life-threatening reactions occurring in more than 5% of patients with generalized MG include musculoskeletal pain (15%), abdominal pain (8%), peripheral edema (8%), fever (7%), herpes simplex infection (8%), and contusion (8%).1

The safety of Soliris in pediatric patients and in pregnant or lactating women has not been established. According to the results of animal studies, Soliris may cause fetal harm.1 


1. Soliris. Highlights of prescribing information. Alexion Pharmaceuticals; 2017. 

Reviewed by Harshi Dhingra, MD, on 2/18/2022.