Amgen's Imdelltra Shows Promising Results in Small Cell Lung Cancer Treatment

Amgen has unveiled groundbreaking phase 3 results for its T-cell engager Imdelltra in previously treated small cell lung cancer (SCLC), marking a significant advancement in the field of oncology. The data, presented at the 2025 American Society of Clinical Oncology (ASCO) annual meeting and simultaneously published in The New England Journal of Medicine, demonstrate Imdelltra's potential to transform the treatment landscape for SCLC patients.

Impressive Survival Benefits and Safety Profile

The DeLLphi-304 trial results show that Imdelltra significantly reduced the risk of death by 40% compared to chemotherapy in SCLC patients who had undergone one line of platinum-based chemotherapy. Patients treated with Imdelltra achieved a median overall survival of 13.6 months, surpassing the 8.3 months observed in the chemotherapy arm.

Notably, the benefits of Imdelltra were consistent across various patient subgroups, regardless of prior PD-1/L1 exposure, presence of brain or liver metastases, or type of previous chemotherapy. The drug demonstrated a 39% reduction in death risk for patients with prior PD-1/L1 inhibitor exposure and a 35% reduction for PD-1/L1-naïve patients.

In addition to survival benefits, Imdelltra exhibited a more favorable safety profile compared to chemotherapy. The incidence of grade 3 or higher treatment-related adverse events was significantly lower in the Imdelltra group (27%) than in the chemotherapy group (62%). Only 3% of patients discontinued Imdelltra due to adverse events, compared to 6% in the control arm.

Impact on Quality of Life and Future Directions

Imdelltra treatment resulted in significantly better outcomes for cancer-related symptoms, particularly shortness of breath and cough, as evidenced by patient-reported changes at Week 19. Although the difference in chest pain scores between the two arms was not significant, the overall impact on patients' quality of life appears promising.

Amgen is currently conducting or planning three phase 3 trials to explore Imdelltra's potential in first-line SCLC treatment. These include studies evaluating Imdelltra in combination with AstraZeneca's Imfinzi as a first-line maintenance treatment for extensive-stage SCLC, as well as investigations into its efficacy in first-line maintenance for limited-stage SCLC.

The success of Imdelltra has sparked interest in DLL3 as a target for cancer therapy. At ASCO 2025, Legend Biotech reported preliminary efficacy results from a phase 1 study of LB2102, a DLL3-targeted CAR-T candidate being developed in partnership with Novartis. While the data are limited, researchers suggest that further exploration of higher dose levels is warranted.

As the pharmaceutical industry continues to make strides in oncology, Imdelltra's promising results in SCLC treatment represent a significant step forward in addressing the unmet needs of patients with this aggressive form of lung cancer.