(SLC-033) Establishing standing cohorts of refractory lupus patients in the fit-for-purpose Real-World Data (RWD) sources to facilitate contextualization of upcoming clinical trial safety data: A feasibility project

Background: Phase I and II clinical trials for cell therapies in rare or niche indications often involve single arm trials with small sample sizes or unblinded control arm trials with potential differences in the follow-up period between standard of care and investigational product. Building standing cohorts in existing RWD sources could mimic the trial populations and provide benchmarks for potential rare or long-term events during the development phase.

Objectives: To explore the feasibility of establishing standing cohorts specific to refractory lupus patients within a RWD source thereby the incidence of T-cell malignancy is evaluated in a pilot study.

Methods: This project is an observational cohort study using secondary US data from the Optum’s de-identified Clinformatics® Data Mart (CDM) database. The population of interest included adult severe refractory systemic lupus erythematosus (SLE) patients with or without lupus nephritis (LN) (Cohort 1) and SLE patients with severe refractory LN (Cohort 2). The Structured Process to Identify Fit-for-Purpose Data (SPIFD) framework for conducting feasibility assessments was followed to predefine the required study elements at the dataset level.
Existing patient identification algorithms were adapted by combining diagnostic codes and treatment episodes. The analysis period was from 01 Jan 2007 to 31 March 2024. The index date was defined specific to each cohort. Patients were required to have continuous enrollment or continuously recorded healthcare activity in their respective health plan for ≥6 months prior to and post index date. The main outcome was the number of eligible patients per cohort in the dataset. Descriptive statistics were used to describe patient characteristics (e.g., age, gender and race), time since SLE diagnosis, total FU time from index date and selected comorbidities.

Results: The final sample size for cohort 1 exceeded the target number of > 500 patients with 1955 eligible patients in Optum CDM. The final sample size for cohort 2 was below expectation with 235 eligible patients in Optum CDM.

Conclusions: It was feasible to establish standing cohorts within the selected RWD source that mimic rare trial populations. The identified RWD source with ongoing data collection can be queried to contextualize the safety outcome(s) of interest from the clinical trial with the existing patient population receiving standard of care in the RWD sources. This project also provided a roadmap for exploring other fit-for-purpose RWD sources (e.g., SLE registries) for potential post-marketing commitment feasibility and planning.