Older Adult Data Underreported in DLBCL Registration Trials Worldwide
Key Clinical Summary
- A systematic review of 12 US Food and Drug Administration (FDA) and European Medicines Agency (EMA) registration trials (2017-2023) in diffuse large B-cell lymphoma (DLBCL) found incomplete reporting of outcomes for adults aged 65 years or older .
- While 83.4% of primary endpoints were fully reported in older subgroups, more than half (53.1%) of secondary endpoints were not reported.
- Baseline characteristics, toxicity, and quality-of-life data for older adults were largely missing across trials.
Incomplete reporting of clinical outcomes in older adults remains a persistent gap in DLBCL trials, according to a systematic review evaluating FDA and EMA registration studies from 2017 to 2023.
Study Findings
Investigators analyzed 12 registration trials supporting 10 approved therapies in DLBCL, including chimeric antigen receptor (CAR) T-cell therapies, antibody-drug conjugates, bispecific antibodies, and monoclonal agents. A total of 2655 patients were enrolled, with 45.8% aged 65 years or older.
Across 92 publications, subgroup reporting for older adults was assessed for completeness. Among 12 primary endpoints, 10 (83.4%) were fully reported, 1 (8.3%) partially reported, and 1 (8.3%) not reported. In contrast, among 66 secondary endpoints, only 25 (37.9%) were fully reported, 6 (9.1%) partially reported, and 35 (53.1%) not reported.
Overall survival was included as a secondary endpoint in all trials, yet 41.7% of studies did not report survival outcomes specifically for older adults. Similarly, progression-free survival and duration of response were inconsistently reported.
Baseline patient characteristics were incompletely reported in older subgroups, with 58.3% of trials lacking such data. No trial included a formal geriatric assessment. Quality-of-life outcomes were assessed in 8 trials but were unreported in 62.5% of cases, and toxicity data were never fully reported for older adults.
Clinical Implications
DLBCL disproportionately affects older adults, with more than half of patients diagnosed at age 65 years or older. Despite this, subgroup reporting in clinical trials remains insufficient to fully inform treatment decisions in this population.
Older adults often have greater comorbidity burden, reduced organ function, and increased vulnerability to treatment-related toxicities. The lack of detailed reporting on efficacy, safety, and quality-of-life outcomes limits clinicians’ ability to assess the benefit-risk profile of newer therapies in real-world settings.
Although enrollment of older adults was relatively high in many trials, the absence of granular subgroup data—particularly for patients aged 75 years or older—may obscure clinically meaningful differences in outcomes. Dedicated subgroup analyses were associated with improved reporting completeness, suggesting a potential strategy for addressing this gap.
The authors noted that “older adults are not just a unique group but also a very heterogeneous group of patients,” emphasizing that incomplete reporting may mask important differences in efficacy and toxicity. They also highlight that “standardization of subpopulation analysis…will better enable benefit-risk profiling” for older adults.
Conclusion
In DLBCL registration trials, primary endpoints are generally reported for older adults, but secondary outcomes, toxicity, and quality-of-life data remain largely incomplete. Improved standardized reporting—including dedicated subgroup analyses—may better support evidence-based treatment decisions for older patients with DLBCL.
Reference
Neuendorff NR, Pugh K, Juthani R, Soudant C, et al. Inclusion, characteristics, and reporting of older patients in recent registration trials for DLBCL. Blood Adv. 2026;10(4):1194-1203. doi:https://doi.org/10.1182/bloodadvances.2025017530
