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How Nucala works

Nucala is indicated as an add-on treatment for severe refractory eosinophilic asthma in adults, adolescents and children aged 6 years and older. Only Nucala 100mgs SC is licensed for use.1

Human interleukin-5 (IL-5) is the major cytokine responsible for the growth and differentiation, recruitment, activation and survival of eosinophils. Mepolizumab is a humanised monoclonal antibody, which targets IL-5 with high affinity and specificity.1

Nucala reduces blood eosinophils to normal levels2-4

Reduction to normal levels in nucala treated patients

*The normal range is based on 5th – 95th percentile values from the general population3
**geometric mean value from COSMOS study. This is a 52 week, open label extension study which evaluated the long term safety and efficacy of mepolizumab. (n=590; SD logs 0.934)2

The evolution of eosinophils

Explore efficacy data

Nucala is indicated as an add-on treatment for severe refractory eosinophilic asthma in adults, adolescents and children aged 6 years and older. Only Nucala 100mg SC is licensed for use1

Nucala is generally well tolerated. Very commonly or commonly reported adverse reactions in clinical trials included: headache; back pain; local injection site reactions; systemic administration-related and hypersensitivity reactions (which can occur after a long duration of treatment); LRTI; UTI; pharyngitis; nasal congestion; upper abdominal pain; eczema and pyrexia.1

The recommended dose of Nucala is 100mg SC once every 4 weeks in adults and adolescents 12 years and older, available in a pre-filled pen, pre-filled syringe or lyophilised powder. The licensed dose of Nucala in children aged 6-11 years is 40mg SC regardless of weight and available in lyophilised powder.1


  1. Nucala SmPC, 2021. Available from Last accessed April 2023.
  2. Lugogo N et al. Long-term efficacy and safety of mepolizumab in patients with severe eosinophilic asthma: a multi-center, open-label, Phase IIIb study. Clin Ther 2016; 38:2058–2070.
  3. Hartl S et al. Blood eosinophil count in the general population: typical values and potential confounders. Eur Respir J 2020; pii: 1901874. doi: 10.1183/13993003.01874-2019 [Epub ahead of print].
  4. Yancey et al. 2017, J Allergy Clin Immunol, 140 (6), 1509-1518
  5. Khurana S et al. Long-term safety and clinical benefit of mepolizumab in patients with the most severe eosinophilic asthma: the COSMEX study. Clin Ther 2019; 41:2041–2056.
  6. Heredia JE;Cell;2013;153;376-388.
  7. Wu D;Science;2011;332;243-7.
  8. Zhu L;PloS one;2013;8;e67613;1-6.
  9. Yang Y, et al. Am J Pathol 1997;151:813-819.
  10. Ramirez GA, et al. Biomed Res Int. 2018;2018:9095275.
  11. Wenzel SE, et al. Am J Respir Crit Care Med. 1999;160:1001–1008.
  12. de Carvalho-Pinto RM, et al. Resp Med. 2012;106:47–56.
  13. Haldar P, et al. Am J Respir Crit Care Med. 2008;178:218–224.
  14. Albers FC, et al. J Asthma. 2018;55:152–160
  15. Wen T, Rothenberg ME. The regulatory function of eosinophils. Microbiol Spectr 2016; 4 doi: 10.1128/microbiolspec. MCHD-0020-2015.
  16. Weller PF, Spencer LA. Functions of tissue-resident eosinophils. Nat Rev Immunol 2017; 17:746–760.

Adverse events should be reported directly to the Health Products Regulatory Authority (HPRA) on their website: Adverse events should also be reported to GlaxoSmithKline on 1800 244 255.

© 2023 GSK group of companies or its licensor.
Trade marks are owned by or licensed to the GSK group of companies.

PM-IE-MPL-WCNT-200013 | April 2023