Breakthrough DLL3-Targeting Therapy Regimen for a Major Solid Tumor

IMDELLTRA Demonstrated Impressive 40% Objective Response Rate, 9.7 Month Median Duration of Response and 14.3 Month Median Overall Survival in Pivotal DeLLphi-301 Study

THOUSAND OAKS, CA, USA I May 16, 2024 I Amgen (NASDAQ:AMGN) today announced that the U.S. Food and Drug Administration (FDA) has approved IMDELLTRA™ (tarlatamab-dlle) for the treatment of adult patients with extensive-stage small cell lung cancer (ES-SCLC) with disease progression on or after platinum-based chemotherapy. IMDELLTRA has received accelerated approval based on the encouraging response rate and duration of response (DoR) observed in clinical studies. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).

Experience the full interactive Multichannel News Release here:

“The FDA’s approval of IMDELLTRA marks a pivotal moment for patients battling ES-SCLC. This DLL3-targeting therapy in ES-SCLC comprises a transformative option demonstrating long-lasting responses in pretreated patients,” said Jay Bradner, M.D., executive vice president, Research and Development, and chief scientific officer at Amgen. “This approval further demonstrates our commitment to addressing aggressive cancers through our second FDA-approved Bispecific T-cell Engager (BiTE®) molecule. IMDELLTRA offers these patients who are in urgent need of new innovative therapies hope, and we’re proud to deliver this long-awaited effective treatment to them.”

“Lung cancer is a complex and devastating disease, and less than 3% of patients with ES-SCLC live longer than five years,” said David P. Carbone, M.D., Ph.D., professor of internal medicine and director of the James Thoracic Oncology Center at the Ohio State University Medical Center.1 “In the DeLLphi-301 trial, the median overall survival was 14.3 months, with 40% of patients responding to treatment with tarlatamab. These responses were remarkably durable, representing a major advancement in the SCLC treatment paradigm.”

IMDELLTRA is the first and only DLL3-targeting Bispecific T-cell Engager therapy that activates the patient’s own T cells to attack DLL3-expressing tumor cells.2 

“After decades of minimal advancements in the SCLC treatment landscape, there is now an effective and innovative treatment option available,” said Laurie Fenton Ambrose, co-founder, president, and CEO of GO2 for Lung Cancer. “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.”

The FDA accelerated approval of IMDELLTRA is based on results from the Phase 2 DeLLphi-301 clinical trial that evaluated IMDELLTRA in patients with SCLC who had failed two or more prior lines of treatment, and who had received the 10 mg every two weeks dosing (Q2W) regimen. Results from the study found that IMDELLTRA at the 10 mg Q2W dose (N=99) demonstrated a robust objective response rate (ORR) of 40% (95% Confidence Interval [CI]: 31, 51) and median DoR of 9.7 months (CI: 2.7, 20.7+). The median overall survival (mOS) was 14.3 months, with final and complete survival data yet to mature.3

The IMDELLTRA label includes a Boxed Warning for cytokine release syndrome (CRS) and neurologic toxicity, including immune effector cell-associated neurotoxicity syndrome (ICANS), in addition to warnings and precautions for cytopenias, infections, hepatotoxicity, hypersensitivity, and embryo-fetal toxicity. The most common (> 20%) adverse reactions reported among patients were CRS (55%), fatigue (51%), pyrexia (36%), dysgeusia (36%), decreased appetite (34%), musculoskeletal pain (30%), constipation (30%), anemia (27%), and nausea (22%). Permanent discontinuations due to treatment-emergent adverse events (TEAEs) were infrequent (7%). CRS was largely confined to the first and second dose, predominantly grade 1 or 2, and was generally managed with supportive care. Details of the Important Safety Information are included below. 

Amgen’s Commitment to Patient Support
Amgen is committed to supporting patients with ES-SCLC and to helping ensure appropriate patients with access to IMDELLTRA. Patients, caregivers, and physicians who need support, tools, or resources can contact Amgen® SupportPlus. Amgen also provides patient assistance for its medicines marketed in the U.S. in a variety of ways, including for uninsured or under-insured patients through the Amgen Safety Net Foundation, a nonprofit patient assistance program sponsored by Amgen that helps qualifying patients access Amgen medicines at no cost.

Amgen to Webcast Investor Call on IMDELLTRA FDA Approval
Amgen will host a webcast call for the investment community on Monday, May 20, 2024 at 1:00 p.m. PT (4:00 p.m. ET). Jay Bradner, M.D., executive vice president, Research and Development, and chief scientific officer at Amgen, Murdo Gordon, executive vice president of Global Commercial Operations, and other members of the Amgen team will participate.

Live audio of the investor call will be simultaneously broadcast over the internet and will be available to members of the news media, investors, and the general public.

The webcast, as with other selected presentations regarding developments in Amgen’s business given by management at certain investor and medical conferences, can be found on Amgen’s website,, under Investors. Information regarding presentation times, webcast availability, and webcast links are noted on Amgen’s Investor Relations Events Calendar. The webcast will be archived and available for replay for at least 90 days after the event.

About IMDELLTRA™ (tarlatamab-dlle)
IIMDELLTRA is a first-in-class immunotherapy engineered by Amgen researchers that binds to both DLL3 on tumor cells and CD3 on T cells, activating T cells to kill DLL3-expressing SCLC cells. This results in the formation of a cytolytic synapse with lysis of the cancer cell.2,4 DLL3 is a protein that is expressed on the surface of SCLC cells in ~85-96% of patients with SCLC, but is minimally expressed on healthy cells, making it an exciting target.3,5

IMDELLTRA™ (tarlatamab-dlle) U.S. Indication
IMDELLTRA™ (tarlatamab-dlle) is indicated for the treatment of adult patients with extensive-stage small cell lung cancer (ES-SCLC) with disease progression on or after platinum-based chemotherapy.

This indication is approved under accelerated approval based on overall response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).

Please see IMDELLTRA™ full Prescribing Information, including BOXED WARNINGS.

About Small Cell Lung Cancer (SCLC)
SCLC is one of the most aggressive and devastating solid tumor malignancies, with a median survival of approximately 12 months following initial therapy and a 3% five-year relative survival rate for ES-SCLC.1,6,7 Current second-line treatments impart a short duration of response (median DoR: 3.3–5.3 months) and limited survival (median OS: 5.8-9.3 months), while current third-line treatments for SCLC, which consist primarily of chemotherapy, yield a short median DoR of 2.6 months and a median OS of 4.4-5.3 months.8-12 SCLC comprises ~15% of the 2.4 million plus patients diagnosed with lung cancer worldwide each year.13-15 Despite initial high response rates to first-line platinum-based chemotherapy, most patients quickly relapse within months and require subsequent treatment options.13

About Tarlatamab Clinical Trials
Amgen’s robust tarlatamab development program includes the DeLLphi clinical trials, which evaluate tarlatamab as both a monotherapy and in combination regimens in earlier lines of SCLC, and DeLLpro clinical trials, which evaluate the efficacy and safety of tarlatamab in neuroendocrine prostate cancer.

In the Phase 1 DeLLphi-300 study, tarlatamab showed responses in 23.4% of patients with encouraging durability in heavily pre-treated patients with SCLC.16 In the Phase 2 DeLLphi-301 study, tarlatamab administered as 10 mg dose every two weeks demonstrated an ORR of 40% in patients with advanced SCLC who had failed two or more prior lines of treatment. In the DeLLphi-301 Phase 2 trial, the most frequent treatment-related adverse events seen with 10 mg Q2W dosing regimen were CRS (51%), pyrexia (32%), and decreased appetite (23%). CRS events were predominantly grade 1 or 2 and occurred most often after the first or second dose.2 Treatment discontinuation for adverse events occurred in 4-7% of patients in the two trials.3,16

Tarlatamab is being investigated in multiple studies including DeLLphi-303, a Phase 1b study investigating tarlatamab in combination with standard of care therapies in first-line ES-SCLC; DeLLphi-304, a randomized Phase 3 trial comparing tarlatamab monotherapy with standard of care chemotherapy in second-line treatment of SCLC; DeLLphi-305, a randomized Phase 3 trial comparing tarlatamab in combination with durvalumab versus durvalumab alone as first-line maintenance treatment in ES-SCLC; DeLLphi-306, a randomized placebo-controlled Phase 3 trial of tarlatamab following concurrent chemoradiotherapy in limited-stage SCLC; and DeLLpro-300, a Phase 1b study of tarlatamab in de novo or treatment-emergent neuroendocrine prostate cancer.17

For more information, please visit

About Bispecific T-Cell Engager (BiTE®) Technology
BiTE technology is a targeted immuno-oncology platform that is designed to engage a patient’s own T cells to any tumor-specific antigen, activating the cytotoxic potential of T cells to eliminate detectable cancer. The BiTE immuno-oncology platform has the potential to treat different cancer types through tumor-specific antigens. The BiTE platform has a goal of leading to off-the-shelf solutions, which have the potential to make innovative T cell treatment available to all providers when their patients need it. For more than a decade, Amgen has been advancing this innovative technology, which has demonstrated strong efficacy in hematological malignancies and now a solid tumor with the approval of IMDELLTRA. Amgen remains committed to progressing multiple BiTE molecules across a broad range of hematologic and solid tumor malignancies, paving the way for additional applications in more tumor types. Amgen is further investigating BiTE technology with the goal of enhancing patient experience and therapeutic potential. To learn more about BiTE technology, visit BiTE® Technology 101.

About Amgen 
Amgen discovers, develops, manufactures and delivers innovative medicines to help millions of patients in their fight against some of the world’s toughest diseases. More than 40 years ago, Amgen helped to establish the biotechnology industry and remains on the cutting-edge of innovation, using technology and human genetic data to push beyond what’s known today. Amgen is advancing a broad and deep pipeline that builds on its existing portfolio of medicines to treat cancer, heart disease, osteoporosis, inflammatory diseases and rare diseases.

In 2024, Amgen was named one of the “World’s Most Innovative Companies” by Fast Company and one of “America’s Best Large Employers” by Forbes, among other external recognitions Amgen is one of the 30 companies that comprise the Dow Jones Industrial Average®, and it is also part of the Nasdaq-100 Index®, which includes the largest and most innovative non-financial companies listed on the Nasdaq Stock Market based on market capitalization.

For more information, visit and follow Amgen on X, LinkedIn, Instagram, TikTok, YouTube and Threads.


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