Adherence and long-term growth: the easypod™ connect observational study (ECOS) in children with growth disorders

OBJECTIVE: The easypod™ connect observational study (ECOS) assessed treatment adherence among paediatric patients receiving growth hormone (GH) via the easypod electronic injection device. DESIGN: ECOS was an open-label, observational, longitudinal study conducted in 24 countries between 2010 and 2016, enrolling children treated with GH. METHODS: The primary endpoint was the rate of treatment adherence during 5 years of follow-up. Impact of adherence on growth outcomes was assessed using Spearman's product-moment correlations. RESULTS AND CONCLUSIONS: 1,190 patients had easypod data available for ≥3 months; most patients had GH deficiency (75%). 606 of these patients were GH-naïve at baseline. Over the first year of monitoring, the median rate of adherence was 93.7% among patients overall and >93.0% in GH-naïve patients, irrespective of the treatment indication. Clinically meaningful improvements in growth rates were observed after 1 year of treatment across all GH indications. Adherence decreased with increasing treatment duration, but the overall median adherence rate remained high after 3 years of follow-up: 87.2% (n=409), 75.5% after 4 years (n=143) and 70.2% after 5 years (n=43). Statistically significant correlations between adherence and 1-year change in height standard deviation score (