Real-World Data Support Outpatient Tarlatamab for Community SCLC Care

Real-world findings from a retrospective study of 90 patients with relapsed/refractory small cell lung cancer (SCLC) suggest that tarlatamab-dlle (Imdelltra) can be feasibly administered in outpatient community oncology settings, with predominantly low-grade cytokine release syndrome (CRS), limited immune effector cell-associated neurotoxicity syndrome (ICANS), and low intensive care unit (ICU) utilization.^1,2

The analysis, presented at the 2026 European Society for Medical Oncology (ESMO) Congress, compared safety outcomes among patients receiving tarlatamab through outpatient, inpatient, and hybrid administration models. CRS occurred in 30%, 47%, and 60% of patients in each respective cohort, while ICANS occurred in 13%, 7%, and 23%.

Tarlatamab is a bispecific T-cell engager targeting delta-like ligand 3 (DLL3) and CD3. Although the therapy has demonstrated clinical benefit in relapsed/refractory SCLC, its potential to cause CRS and ICANS has historically required extended monitoring during treatment initiation, creating logistical considerations for community oncology practices.

“The real-world results give us greater confidence that tarlatamab can be delivered outside the traditional inpatient setting in appropriately selected patients,” Trevor Feinstein, MD, of Piedmont Cancer Institute and lead author of the abstract, stated in a news release.

Study Design and Patient Characteristics

Investigators conducted a retrospective analysis of 90 patients with SCLC treated with tarlatamab across OneOncology partner practices. Patients were equally distributed among 3 administration models: outpatient (n = 30), inpatient (n = 30), and hybrid (n = 30). The hybrid model involved administration in an outpatient infusion center followed by hospital observation.

Baseline performance status was similar across cohorts, with ECOG scores of 0 or 1 reported in approximately three-quarters of patients in each group. However, the hybrid cohort had a higher prevalence of brain metastases (67%) and liver metastases (77%) than the other cohorts.

Safety Outcomes Across Administration Settings

All CRS events in the outpatient cohort were grade 1. In comparison, grade 2 CRS occurred in 10% of inpatient patients, while 40% of hybrid patients experienced grade 2 or higher CRS, including 1 grade 4 event.

Two patients (7%) in the hybrid cohort required ICU care for CRS, compared with none in the outpatient or inpatient cohorts. ICANS occurred in 13%, 7%, and 23% of patients in the outpatient, inpatient, and hybrid groups, respectively. One outpatient patient (3%) required ICU care for ICANS.

Treatment for CRS was more frequently administered in the hybrid cohort (60%) than in the outpatient (27%) or inpatient (47%) cohorts. Corticosteroids and tocilizumab (Actemra) were the primary interventions reported.

Disease Control and Clinical Implications

Disease control rates (DCRs), defined by complete response, partial response, or stable disease, were similar across the 3 administration settings. The outpatient cohort had a complete response rate of 3%, partial response rate of 30%, and stable disease rate of 13%. Corresponding rates were 7%, 30%, and 17% in the inpatient cohort and 7%, 23%, and 13% in the hybrid cohort.

The findings highlight the potential for community oncology practices to administer tarlatamab without requiring routine inpatient monitoring for every patient. The low incidence of severe CRS and limited ICU utilization in the outpatient cohort suggest that selected patients may be candidates for outpatient treatment, potentially reducing the need for hospital-based administration and expanding access to bispecific T-cell engager therapies.

However, the differences in CRS severity across cohorts underscore the importance of patient selection and individualized monitoring. The hybrid cohort had a higher prevalence of brain and liver metastases, which investigators suggested may have contributed to the greater CRS severity observed in this group. These findings raise the possibility that patients with greater disease burden or other risk factors may benefit from more intensive observation during treatment initiation.

Although the retrospective design and small cohort size limit direct comparisons between administration models, the results provide real-world evidence supporting further evaluation of risk-adapted outpatient treatment strategies. Prospective studies are needed to establish which patients can safely receive tarlatamab in outpatient settings and what monitoring protocols are appropriate across community oncology practices.

REFERENCES

1. Feinstein T, et al. Real-World Safety and Outcomes of Outpatient, Inpatient, and Hybrid Tarlatamab Administration in Relapsed/Refractory Small Cell Lung Cancer. Abstract 3852P. Presented at: 2026 European Society for Medical Oncology Congress; 2026.

2. Real-World Data from OneOncology Practices Show Tarlatamab Can Be Administered Safely in the Outpatient Community Oncology Setting. News release. OneOncology. October 27, 2026. Accessed October 30, 2026. https://tinyurl.com/yftnyhmp