2. Academic Validation
  3. Ifinatamab Deruxtecan in Patients With Extensive-Stage Small Cell Lung Cancer: Primary Analysis of the Phase II IDeate-Lung01 Trial

Ifinatamab Deruxtecan in Patients With Extensive-Stage Small Cell Lung Cancer: Primary Analysis of the Phase II IDeate-Lung01 Trial

  • J Clin Oncol. 2026 Feb;44(4):261-273. doi: 10.1200/JCO-25-02142.
Charles M Rudin 1,  Melissa L Johnson 2,  Luis Paz-Ares 3,  Makoto Nishio 4,  Christine L Hann 5,  Nicolas Girard 6,  Pedro Rocha 7,  Hidetoshi Hayashi 8,  Tetsuya Sakai 9,  Yu Jung Kim 10,  Haichuan Hu 11,  Meng Qian 12,  Jasmeet Singh 12,  Juliette Godard 13,  Mei Tang 12,  Myung-Ju Ahn 14
Affiliations

Affiliations

  • 1 Memorial Sloan Kettering Cancer Center, New York, NY.
  • 2 Sarah Cannon Research Institute, Nashville, TN.
  • 3 Hospital Universitario 12 de Octubre, Madrid, Spain.
  • 4 The Cancer Institute Hospital of the Japanese Foundation for Cancer Research, Tokyo, Japan.
  • 5 Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD.
  • 6 Institut Curie, Paris, France.
  • 7 Vall d'Hebron University Hospital and Vall d'Hebron Institute of Oncology, Barcelona, Spain.
  • 8 Kindai University, Osaka, Japan.
  • 9 National Cancer Center Hospital East, Kashiwa, Japan.
  • 10 Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Republic of Korea.
  • 11 Merck & Co, Inc, Rahway, NJ.
  • 12 Daiichi Sankyo, Inc, Basking Ridge, NJ.
  • 13 Daiichi Sankyo SAS, Paris, France.
  • 14 Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
PMID: 41086386 DOI: 10.1200/JCO-25-02142
Abstract

Purpose: Treatment options for patients with recurrent or progressive extensive-stage small cell lung Cancer (ES-SCLC) are limited. This phase II trial evaluated the efficacy and safety of ifinatamab deruxtecan (I-DXd), a B7 homolog 3-directed antibody-drug conjugate, in patients with previously treated ES-SCLC.

Methods: Patients were randomly assigned to receive I-DXd 8 or 12 mg/kg intravenously once every 3 weeks in part 1 (dose optimization) and received I-DXd 12 mg/kg in part 2 (extension). The primary end point was objective response rate (ORR) by blinded independent central review per RECIST, version 1.1.

Results: Overall, 183 patients received I-DXd: 88 in part 1 (8 mg/kg, n = 46; 12 mg/kg, n = 42) and 95 in part 2. The median number of previous lines of treatment was two. In the total 12-mg/kg group from parts 1 and 2 (n = 137), the confirmed ORR was 48.2% (95% CI, 39.6 to 56.9), median duration of response was 5.3 (95% CI, 4.0 to 6.5) months, median time to response was 1.4 (range, 1.0-8.1) months, median progression-free survival was 4.9 (95% CI, 4.2 to 5.5) months, and the 9-month overall survival estimate was 59.1%. Any-grade treatment-related adverse events (TRAEs) occurred in 89.8% of patients (grade ≥3, 36.5%). The most common TRAEs were nausea (43.1%), anemia (34.3%), and neutropenia (34.3%). TRAEs associated with treatment discontinuation and death were reported in 9.5% and 4.4% of patients, respectively. Treatment-related interstitial lung disease (ILD) as determined by the ILD adjudication committee was reported in 12.4% of patients (grade ≥3, 4.4%).

Conclusion: I-DXd 12 mg/kg once every 3 weeks showed promising efficacy in patients with previously treated ES-SCLC. The observed safety profile was consistent with previous reports, with no new safety signals identified.

Figures
Products