Suboptimal adherence to prescribed daily growth hormone regimen among medicaid beneficiaries in the United States.

OBJECTIVE: The objective of this retrospective cohort study was to describe the adherence and discontinuation patterns of somatropin over 3 years among children with pGHD insured by Medicaid across the United States. METHODS: Eligible children were aged ≥3 and <16 years with Medicaid coverage, diagnosed with pGHD, and had ≥2 new prescriptions for somatropin between 1 July 2014 and 31 December 2018. Four non-exclusive patient cohorts were constructed (≥3, 12, 24, and 36 months of continuous enrollment after initial prescription). Suboptimal adherence was defined as medication possession ratio <0.80, and discontinuation as a gap of >60 days between somatropin fills. Logistic and proportional hazards regression methods were used to estimate odds of suboptimal adherence and time to discontinuation, respectively. RESULTS: In the 12-month cohort (n = 3623), mean age was 10.5 ± 3.2 years, 70.8% were male, 44.4% White, 29.1% Hispanic, 7.1% Black, and 1.7% Asian. At months 12, 24, and 36, the proportion with suboptimal adherence was 40.9, 50.4, 54.4%, respectively, and 49.2% of patients with ≥3 months of follow-up discontinued therapy. At 12 months, lower age and race/ethnicity (Black vs. White referent) had greater odds of suboptimal adherence. Discontinuation was associated with Black (vs. White referent) race and geographic region. CONCLUSIONS: Sociodemographic characteristics may be risk factors for suboptimal adherence and/or discontinuation of prescribed somatropin therapy. Improving GH regimen adherence among this at-risk population, and specifically among subgroups at highest risk, is warranted to improve clinical outcomes.

A 4-Year, Open-Label, Multicenter, Randomized Trial of Genotropin® Growth Hormone in Patients with Idiopathic Short Stature: Analysis of 4-Year Data Comparing Efficacy, Efficiency, and Safety between an Individualized, Target-Driven Regimen and Standard Dosing.

BACKGROUND/AIMS: Growth hormone (GH) treatment regimens for children with non-GH-deficient, idiopathic short stature (ISS) have not been optimized. To compare the efficacy, efficiency, and safety of an individualized, target-driven GH regimen with standard weight-based dosing after 4 years of treatment. METHODS: This is a 4-year, open-label, multicenter, randomized trial comparing individualized, formula-based dosing of Genotropin® versus a widely used ISS dose of Genotropin®. Subjects were prepubertal, had a bone age of 3-10 years for males and 3-9 years for females, were naive to GH treatment, and had a height standard deviation score (Ht SDS) of -3 to -2.25, a height velocity <25th percentile for their bone age, and peak stimulated GH >10 ng/ml. After the first 2 years, the individualized-dosing group was further randomized to either 0.18 or 0.24 mg/kg/week. RESULTS: At 4 years, subjects in all treatment regimens achieved similar average height gains of +1.3 SDS; however, the individualized dosing regimen utilized less GH to achieve an equivalent height gain. CONCLUSION: Individualized, formula-based GH dosing, followed by a dose reduction after 2 years, provides a more cost-effective growth improvement in patients with ISS than currently employed weight-based regimens.