In a study published in The American Journal of Respiratory Critical Care Medicine, investigators compared intravenous reslizumab (Cinqair) and mepolizumab (Nucala). Both of them are used for moderate to severe persistent asthma and they both neutralize IL-5, which produces blood eosinophilia and leads to severe eosinophilic asthma.
A randomized, placebo controlled trial was used to assess the efficacy of intravenous Cinqair in 10 patients with eosinophilic asthma whom a 1 year trial of subcutaneous Nucala (100 mg every 4 weeks) failed. All patients received 2 IV infusions of placebo followed by 4 infusions of Cinqair (3 mg/kg) or placebo.
Compared with placebo, Cinqair decreased sputum eosinophil counts, blood eosinophil counts and sputum eosinophil peroxidase levels. Patients on Cinqair had greater improvements in Asthma Control Questionnaire scores. The investigators summarized that intravenous reslizumab (Cinqair) is superior to subcutaneous mepolizumab (Nucala) in controlling severe asthma.
This was a very, very small study with only 10 patients, so it is probably best not to draw too many conclusions from it. There are other parameters that also need to be taken into account which were not mentioned in the study, such as rate of exacerbations, albuterol usage, ER visits, hospitalizations to name a few. Although Cinqair did reduce sputum eosinophils more than Nucala, a clinical correlation is still needed.
It is important to speak to your asthma doctor to see which biologic asthma medication is right for you if you have severe asthma. There are many on the market and more are coming out in the near future. The field of biologics for asthma is becoming very personalized and if you do have severe asthma that is not controlled by conventional asthma medication, it is important to find the right one which is best for you.