FDA Approves Tarlatamab for Extensive-Stage SCLC

FDA Approves Tarlatamab for Extensive-Stage SCLC

The FDA granted accelerated approval to the bispecific T-cell engager tarlatamab-dlle (Imdelltra) for the treatment of extensive-stage small cell lung cancer (SCLC) whose disease progressed on or after platinum-based chemotherapy.¹

This marks the first and only DLL3-targeting bispecific T-cell engager therapy, according to a press release from Amgen, the manufacturer of the therapy.²

"The FDA's approval of Imdelltra marks a pivotal moment for patients battling [extensive-stage] SCLC," Jay Bradner, MD, executive vice president of research and development and chief scientific officer at Amgen, said in the release. "This DLL3-targeting therapy in [extensive-stage] SCLC comprises a transformative option demonstrating long-lasting responses in pretreated patients."

This approval is based on efficacy findings from the DeLLphi-301 (NCT05060016) trial, according to a release from the FDA.¹ In this open-label, multicenter, multicohort study, researchers analyzed data from 99 patients with relapsed/refractory extensive-stage SCLC who received tarlatamab until disease progression or unacceptable toxicity. Of note, patients with interstitial lung disease, symptomatic brain metastases, or non-infectious pneumonitis were excluded from the trial.

The major efficacy outcome measures for this trial were overall response rate (ORR) per RECIST 1.1 and duration of response (DOR), as determined by blinded independent central review.

The ORR in the trial was 40% (95% CI, 31%-51%) with a median DOR of 9.7 months (range, 2.7-20.7+).

"Lung cancer is a complex and devastating disease, and less than 3% of patients with [extensive-stage] SCLC live longer than 5 years," David P. Carbone, MD, PhD, professor of internal medicine and director of the James Thoracic Oncology Center at the Ohio State University Medical Center, said in Amgen's release.² "I the DeLLphi-201 trial, the median overall survival was 14.3 months, with 40% of patients responding to treatment with tarlatamab. These responses were remarkable durable, representing a major advancement in the SCLC treatment paradigm."

There were 69 patients who had available data on their platinum sensitivity status.¹ The ORR was 52% (95% CI, 32%-71%) in the 27 patients with platinum-resistant SCLC, which was defined as progression in fewer than 90 days after the last dose of platinum therapy. For patients with platinum-sensitive SCLC (n = 42), defined as progression at least 90 days after the last dose of platinum therapy, the ORR was 31% (95%, 18%-47%).

The FDA noted that the prescribing information for tarlatamab includes a Boxed Warning for serious or life-threatening cytokine release syndrome (CRS) and neurologic toxicity including immune effector cell-associated neurotoxicity syndrome (ICANS).

The most common adverse reactions, occurring in at least 20% of patients, included fatigue, CRS, dysgeusia, pyrexia, musculoskeletal pain, decreased appetite, anemia, constipation, and nausea. In addition, the most common grade 3 or 4 laboratory abnormalities, occurring in at least 5% of patients, included decreased sodium, decreased lymphocytes, increased uric acid, decreased hemoglobin, decreased total neutrophils, decreased potassium, and increased activated partial thromboplastin time.

Treatment-emergent adverse events leading to permanent discontinuations of tarlatamab were infrequent, occurring in 7% of patients, according to the release from Amgen.² CRS often occurred during the first and second dose of tarlatamab, was mainly grade 1 and 2, and was typically managed with supportive care.

The recommend dose of tarlatamab, according to the FDA’s release, is an initial dose of 1 mg administered via intravenous infusion over 1 hour on Cycle 1 Day 1, followed by 10 mg on Cycle 1 Day 8 and Day 15, then every 2 weeks after that until unacceptable toxicity or disease progression. C

"After decades of minimal advancements in the SCLC treatment landscape, there is now an effective and innovative treatment option available," Laurie Fenton Ambrose, cofounder, president, and CEO of GO2 for Lung Cancer, said in the release from Amgen.² "Today's FDA approval marks a significant milestone for the SCLC community, as the availability of a targeted bispecific therapy brings forward new possibilities to those living with this aggressive disease."

References

1. FDA grants accelerated approval to tarlatamab-dlle for extensive stage small cell lung cancer. News release. FDA. May 16, 2024. Accessed May 16, 2024. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-tarlatamab-dlle-extensive-stage-small-cell-lung-cancer
2. FDA Approves Imdelltra (Tarlatamab-dlle), The First and Only T-Cell Engager Therapy for the Treatment of Extensive-Stage Small Cell Lung Cancer. News release. Amgen. May 16, 2024. Accessed May 17, 2024. https://www.amgen.com/newsroom/press-releases/2024/05/fda-approves-imdelltra-tarlatamabdlle-the-first-and-only-tcell-engager-therapy-for-the-treatment-of-extensivestage-small-cell-lung-cancer