OBJECTIVES:

While many studies have investigated compliance with omalizumab (OMA) in asthma patients, questions remain about exposure patterns. We aimed to identify clusters of OMA exposure patterns in asthma patients, identifying OMA long-term discontinuation (≥ 1 year), separately for adults and children.

METHODS:

The French Healthcare Database System (SNDS) was used to select asthma patients who initiated OMA (T₀) between Jan-2009 and Dec-2019, aged ≥ 6 years at T₀, treated for ≥ 16 weeks, with ≥ 2 years of follow-up.

OMA exposure was modelled individually using dispensing records. Clusters were identified through optimal matching and Hierarchical Ascending Classification (HAC). Variables explaining patient distribution within the different clusters were identified using multinomial logistic regression (p-value=0.10).

RESULTS:

A total of 8,726 adults and 1,483 children were selected, with a median follow-up of 53.7 months. Three clusters were identified, for adults and children respectively: Cluster1-Continuous exposure (63.4% - 54.6%), Cluster2-OMA long term discontinuation without resumption (26.7% - 41%), Cluster3-OMA long term discontinuation with resumption (9.9% - 4.4%). For Cluster2 and Cluster3, median persistence – before long-term discontinuation - was 44.0 and 16.3 months for adults, and 45,0 and 19,7 months for children. Patients with continuous exposure (Cluster1) were significantly older, were more often male, more had allergic ground and obesity, less had markers of asthma control (OCS, hospitalization for asthma) before T₀.

Same explanatory variables were found for children, excepted for obesity and asthma markers.

CONCLUSIONS:

The SOLAIR study is the first real-life study that characterizes OMA exposure patterns in more than 10,000 patients over a 5-year follow-up. It confirms the diversity of OMA exposure patterns, with more than two-third of patients with long-term persistence to OMA.

An analysis of markers of uncontrolled asthma available in the SNDS and comorbidities related to asthma will allow a better characterization of patients who discontinue OMA.