Epidemiology and patient journey of Rett syndrome in the United States: a real-world evidence study.

Background: Rett syndrome (RTT) is a neurodevelopmental disorder that almost exclusively affects females and is associated with high clinical burden. However, literature characterizing the real-world journey of patients with RTT is limited. This study provided an overview of the epidemiology, patient characteristics, clinical manifestations, healthcare resource utilization (HRU), costs, and treatment patterns of patients with RTT in the US.

Methods: IQVIA™ Medical Claims Data and Longitudinal Prescription Data (11/01/2016-10/31/2019) were used to identify female patients with RTT, with the first observed diagnosis defined as the index date. Annual incidence and prevalence of RTT were assessed over the entire study period; clinical manifestations, all-cause and RTT-related HRU and costs, and treatment patterns were evaluated during the observation period-from the index date to end of clinical activity or end of data availability, whichever occurred first. Results were further stratified into pediatric (< 18 years) and adult (≥ 18 years) subgroups.

Results: In 2019, prevalence and incidence of RTT was 0.32 and 0.23 per 10,000 enrollees, respectively. Among 5,940 female patients (pediatric: 3,078; adult: 2,862) with mean observation period of 2.04 years, the most prevalent clinical manifestations were neurological disorders (72.8%), gastrointestinal/nutritional disorders (41.9%), and orthopedic disorders (34.6%). The incidence rate of all-cause HRU was 44.43 visits per-patient-per-year and RTT-related HRU comprised 47% of all-cause HRU. Mean all-cause healthcare costs were $40,326 per-patient-per-year, with medical costs driven by home/hospice care visits, therapeutic services, outpatient visits, and inpatient visits. RTT-related healthcare costs comprised 45% of all-cause healthcare costs. The most prevalent supportive therapy and pharmacologic agent were feeding assistance (37.9%) and antiepileptic drugs (54.8%), respectively. Trends were similar by subgroup; although, rates of HRU were generally higher among pediatric patients relative to adult patients (all-cause: 52.43 and 35.86, respectively), which translated into higher mean healthcare costs (all-cause: $45,718 and $34,548, respectively).

Conclusions: Patients with RTT have substantial disease burden, including prevalent clinical manifestations, high rates of HRU and annual healthcare costs, and reliance on pharmacologic and supportive therapies. These findings underscore the unmet need for effective therapies to target the multifactorial manifestations of RTT.