Daily Injections Linked to Caregiver Desire for Weekly Pediatric Growth Hormone Regimens

A nationwide cross-sectional survey conducted across Japan has revealed that caregivers administering once-daily growth hormone injections to children with pediatric growth hormone deficiency express a markedly stronger desire to alter injection schedules compared to caregivers using once-weekly alternatives. Published in Drugs – Real World Outcomes, the observational investigation evaluated real-world treatment perceptions, unmet management needs, and reported satisfaction among 187 eligible family caregivers caring for pediatric patients aged 3 to 14 years. The research team identified that nearly half of the respondents in the daily injection group sought a change in administration frequency, a rate more than double that observed among caregivers whose children received once-weekly injections. While overall treatment satisfaction and caregiver-assessed injection pain scores appeared statistically comparable across the two cohorts in cross-sectional comparisons, daily administration independently predicted an increased caregiver desire to transition to alternative dosing schedules.

Epidemiological investigations in European pediatric cohorts have previously estimated the condition’s annual incidence between one in 28,800 and one in 46,700 individuals, while national pediatric registries in Japan document approximately 1,400 to 2,000 newly diagnosed pediatric cases every year. Established Japanese clinical guidelines recommend the subcutaneous administration of recombinant somatropin at a weekly dosage of 0.175 milligrams per kilogram of body weight, conventionally divided into equal doses administered across six or seven days each week. However, clinicians and researchers have long recognized that the demanding nature of daily injections poses chronic adherence challenges for families.

The therapeutic landscape for pediatric growth hormone deficiency in Japan underwent a significant shift following regulatory approvals of long-acting, once-weekly recombinant formulations, beginning with somapacitan in 2021 and somatrogon in 2022. Emerging clinical literature published after 2022 suggested that moving from daily administration to weekly dosing could alleviate overall treatment burden, support enhanced compliance, and elevate overall health-related quality of life for young patients and their families. In pediatric endocrinology, reduced injection frequency and minimized procedural pain consistently rank among the most prominent factors governing treatment preferences for both pediatric patients and their guardians. Within Japan, this clinical decision occurs under unique structural conditions: universal health insurance coverage and municipal subsidy initiatives for specific chronic pediatric diseases effectively eliminate significant out-of-pocket financial disparities for families. Because these national programs allow households to select treatments based primarily on individual values, clinical needs, and procedural preferences rather than household income, evaluating real-world caregiver experiences following the introduction of once-weekly options became essential.

To investigate these evolving real-world dynamics, the researchers designed an observational, nationwide online survey implemented between June 14 and June 24, 2024. Study participants were identified and screened from extensive nationwide consumer research panels maintained by INTAGE Inc. and Rakuten Insight Global, Inc., which collectively include hundreds of thousands of individuals sharing personal health and medical information. The study authors adopted a natural allocation sampling method without predefined quotas or stratified restrictions, inviting all respondents who satisfied the strict inclusion criteria to complete the comprehensive questionnaire. Eligible participants were parents or guardians of children aged 3 to 14 years diagnosed with pediatric growth hormone deficiency, had primary responsibility for administering injections, and reported an ongoing therapy duration of at least three months. To maintain robust data integrity, all survey questions were mandatory, eliminating missing entries across analyzed records, while data validation protocols removed duplicate households and illogical response sets. The final analyzed population comprised 187 verified caregivers.

The resulting study cohort included 137 caregivers administering once-daily injections and 50 caregivers administering once-weekly injections, reflecting the ongoing clinical transition toward newer long-acting formulations. Among the combined respondents, 57.2 percent were female, with a mean caregiver age of 41.5 years, and 61.0 percent were employed in full-time occupations. Notably, full-time employment was significantly more prevalent among caregivers in the once-weekly cohort than in the once-daily cohort, reaching 76.0 percent versus 55.5 percent, while unemployment was considerably higher in the daily cohort at 18.2 percent versus 2.0 percent. The treated pediatric patients had a mean age of 8.3 years, and 59.9 percent were male. Overall mean duration of growth hormone therapy was 3.6 years, with daily users reporting significantly longer treatment histories than weekly users. Most children received medical care within pediatrics departments, but clinic visit patterns differed significantly: 76.0 percent of weekly cohort patients visited clinics at least monthly, compared to only 47.4 percent of daily cohort patients.

Caregivers identified clinical effectiveness as their leading priority when selecting a growth hormone therapy, cited by 74.3 percent of the overall cohort, followed closely by safety and low side-effect risks at 58.3 percent and procedural convenience at 52.4 percent. However, prioritizing a low injection frequency differed sharply between the two groups, chosen by 40.0 percent of once-weekly caregivers but only 19.7 percent of once-daily caregivers. When asked to evaluate their primary unmet clinical needs regarding ongoing injection therapy, caregivers across the entire cohort most frequently highlighted procedural pain at 35.8 percent, therapeutic effectiveness at 29.4 percent, and injection frequency at 26.2 percent. The once-daily cohort exhibited statistically significantly higher levels of unmet needs across several critical domains compared to the once-weekly group, including a greater desire for less injection pain at 40.9 percent versus 22.0 percent, less injection frequency at 30.7 percent versus 14.0 percent, and enhanced flexibility in injection timing at 19.7 percent versus 6.0 percent.

The survey demonstrated a pronounced divergence between cohorts regarding their satisfaction with their current injection schedule and their motivations for continuing it. When asked why their child received their current injection frequency, 27.7 percent of daily caregivers stated they had experienced no chance to switch formulations, compared to only 10.0 percent in the weekly group. Furthermore, 47.4 percent of daily caregivers expressed an explicit desire to alter their child’s injection frequency, compared with 22.0 percent of weekly caregivers. To isolate variables independently driving this desire to switch regimens, researchers executed a multivariable logistic regression analysis controlling for potential confounding factors. Current once-daily administration emerged as the strongest independent predictor, conferring more than a fivefold increase in the likelihood of desiring a schedule change, with an adjusted odds ratio of 5.30 and a 95 percent confidence interval spanning 2.22 to 13.7. Additional independent predictors included preschool status relative to elementary school attendance, male patient sex, and having previous experience altering injection schedules.

Exploration of injection scheduling demonstrated that 73.8 percent of children in the overall study population received their growth hormone administration immediately before bedtime. However, while virtually all daily cohort respondents adhered to a strict schedule, 16.0 percent of weekly caregivers reported maintaining no specified injection time during the day, highlighting the unique operational flexibility offered by long-acting regimens. Across the entire sample, 67.9 percent of caregivers acknowledged having missed or forgotten an injection dose at least once since initiating therapy, with reported missed administrations reaching 78.8 percent in the daily cohort compared to 38.0 percent in the weekly cohort. Notably, all nine caregivers who reported having no specified injection time indicated that they had never missed an injection. Detailed analyses of caregivers seeking schedule changes revealed divergent priorities: daily users desiring weekly dosing prioritized frequency reductions, whereas the small subset of weekly users seeking daily regimens cited injection site discomfort and safety monitoring concerns as primary motivators.

Assessment of perceived procedural pain using a standard numeric rating scale from zero to ten revealed identical subjective ratings between cohorts, averaging 4.45 in the daily group and 4.42 in the weekly group. Similarly, between-group evaluations utilizing the validated Treatment Satisfaction Questionnaire for Medication version II showed no statistically significant differences in global satisfaction, effectiveness, convenience, or side effects when respondents evaluated only their current medication. However, the study authors emphasized that these cross-sectional comparisons evaluated distinct patient groups and remained subject to status-quo bias and post-hoc rationalization. In contrast, an exploratory within-subject analysis examining caregivers with direct experience using both formulations revealed striking differences. Among families who had transitioned from daily to weekly therapy, satisfaction scores were significantly superior for the weekly regimen in both the side effects and convenience domains. These experienced caregivers also reported meaningful reductions in overall caregiver burden, aligning with earlier clinical trials demonstrating the tangible lifestyle advantages of reducing procedural frequency.

Interpreting these findings, the study authors concluded that many Japanese families managing pediatric growth hormone deficiency on daily injection protocols may be missing critical opportunities to re-evaluate their therapeutic choices. Because stable patients on established daily regimens frequently attend fewer clinic visits and experience shorter consultations, discussions regarding newly introduced long-acting options are often unintentionally bypassed. The researchers emphasized that bridging this communication gap requires the active promotion of shared decision-making, an evidence-based clinical process wherein physicians and families collaboratively align therapeutic plans with patient lifestyle, emotional needs, and acceptable procedural burdens. Nevertheless, the investigators acknowledged several methodological limitations, including the cross-sectional observational design that establishes statistical associations rather than causal effects, potential self-selection bias within commercial consumer panels, reliance on caregiver proxy reports for child pain experiences, and unmeasured clinical nuances such as pubertal development stages. They advocated for future confirmatory investigations incorporating treating physicians to further advance patient-centered pediatric endocrinology.

Subject of Research: Caregiver treatment experiences and injection frequency preferences in pediatric growth hormone deficiency

Article Title: Caregiver Experiences with Daily and Weekly Growth Hormone Injections in Japanese Children: A Cross-sectional Survey

Article References: Takasawa, K., Sato, T., Ebata, N., Sonohara, Y., & Nishi, R. (2026). Caregiver Experiences with Daily and Weekly Growth Hormone Injections in Japanese Children: A Cross-sectional Survey. Drugs – Real World Outcomes. https://doi.org/10.1007/s40801-026-00595-1

Image Credits: AI Generated

DOI: 10.1007/s40801-026-00595-1

Keywords: Pediatric Growth Hormone Deficiency, Growth Hormone Injections, Caregiver Burden, Shared Decision-Making, Treatment Satisfaction, Somatropin, Pediatric Endocrinology, Real-World Evidence, Caregiver, Experiences, Daily, Weekly