Top KOLs Discussing DeLLphi-305
DeLLphi-305 Key Slides & Visuals
DeLLphi-305 Top Tweets
𝕏🚨Hot off the press! In #SCLC, tarlatamab plus durvalumab in 1L ES-SCLC shows OS improvement! Looking forward to the full data! @LungCancerRx https://t.co/H4sBvgIkm0
𝕏🚨🔥‼️@OncoAlert Hot off the press. #BigNews #PressRelease by @Amgen ⭐️ #DeLLphi305 phase 3 trial of: ❇️1st line maintenance #Tarlatamab + #Durvalumab) vs #Durvalumab alone in patients with #ExtensiveStage #SmallCell #LungCancer after initial induction Tx with Chemo + Durvalumab. Showed: ✅Statistically Significant & Clinically meaningful ⬆️#OverallSurvival (#OS) Benefit. 👇🏻 https://t.co/qOh6UPlvaU
𝕏Dellphi-305 trial of Imfinzi + Imdelltra in 1L ES-SCLC maintenance toplined positive. What are the odds this'll be at ESMO? $AZN $AMGN https://t.co/6YObwpSGZ3 https://t.co/rWA8SmpDJw
𝕏🚨 Landmark development in ES-SCLC! Phase 3 DeLLphi-305 has shown a statistically significant and clinically meaningful OS benefit with tarlatamab (IMDELLTRA) + durvalumab versus durvalumab alone as 1L maintenance after platinum–etoposide + durvalumab. PFS and ORR also improved. A potentially important new chapter in ES-SCLC maintenance therapy. Looking forward to full data @StephenVLiu @TejasPatilMD @LauraAlderMD @IASLC
𝕏The kind of news we’ve been waiting for in ES-SCLC: an OS benefit ✅️ First-line maintenance tarlatamab + durvalumab 🔥 https://t.co/yDa6acdBeT
𝕏Just one word - starlatamab! A star was born last year at #ASCO25 and looks like now found a steady partner in durvalumab! https://t.co/7YSywJwf60 https://t.co/DAHOJUitwq
𝕏JUST IN: DeLLphi-305 study met its primary endpoint of overall survival combining tarlatamab (DLL3 BiTE) with PDL1 inhibitor Durvalumab as maintenance after 1L chemotherapy for extensive-stage small cell lung cancer ! Also RR/PFS significant Trial led by @DanaFarber @sands_jacob ! Via @PRNews https://t.co/mbVxkzeAmz
𝕏📢Very exciting news for ES-SCLC! 🔥 DeLLphi-305 meets its primary OS endpoint with tarlatamab + durvalumab as first-line maintenance, with significant improvements also reported in PFS and ORR. Looking forward to seeing the full results! 👀 @OncoAlert @ManuelDomine @GlopesMd @weoncologists @MedwatchHQ @OpenMedKate
𝕏Just received this. The golden era in SCLC! The DeLLphi-305 (Phase 3 Study in First-Line ES-SCLC Following Platinum, Etoposide and Durvalumab) OS Interim Analysis has been conducted. The analysis has demonstrated a statistically significant and clinically meaningful improvement in overall survival with IMDELLTRA® (tarlatamab-dlle) in combination with AstraZeneca's Imfinzi® (durvalumab) compared to durvalumab alone. https://t.co/DXLmkDT5Yz
About the DeLLphi-305 Trial
Extensive-stage small cell lung cancer almost always relapses after first-line platinum–etoposide plus a PD-L1 inhibitor, and frontline survival gains have been rare. DeLLphi-305 tests whether introducing tarlatamab — a DLL3-targeted Bispecific T-cell Engager (BiTE) — during the maintenance phase, in combination with continued durvalumab, extends survival before relapse occurs.
On September 8, 2026, Amgen announced the study met its primary endpoint at a pre-specified interim analysis, with a statistically significant and clinically meaningful overall survival benefit plus significant PFS and ORR improvements — the first Phase 3 BiTE result in the 1L maintenance setting. The program builds on DeLLphi-301 (accelerated approval, May 2024), the confirmatory DeLLphi-304 (full FDA approval in 2L+, Nov 2025), and the Phase 1b DeLLphi-303, which reported median OS of 25.3 months for tarlatamab plus anti–PD-L1 maintenance at WCLC 2025 — Phase 1b data reported separately from this Phase 3 readout. Physicians on this page framed the readout as a landmark for a disease where, as trial lead Jacob Sands' colleagues note, substantial survival improvements are rare.
Trial Methodology & Results
Study Design
Global (international), randomized (1:1), open-label Phase 3; 563 patients randomized; design slide planned ~275 per arm.
Population
Adults with ES-SCLC who completed 3–4 cycles of platinum/etoposide with concurrent durvalumab as first-line treatment without disease progression; no symptomatic CNS metastases; ECOG PS 0–1.
Interventions
Tarlatamab IV every 2 weeks + durvalumab IV every 4 weeks vs durvalumab IV every 4 weeks, until progression or unacceptable toxicity.
Endpoints
Primary: overall survival. Secondary: PFS, ORR, DCR, DoR, TTP, safety, quality of life.
Mechanism
Tarlatamab directs cytotoxic T cells to DLL3-expressing SCLC cells (BiTE platform); durvalumab maintains PD-L1 checkpoint blockade from induction.
Sponsors
Amgen (tarlatamab); durvalumab supplied as AstraZeneca’s Imfinzi.
Efficacy — topline only
Tarlatamab plus durvalumab delivered a statistically significant and clinically meaningful improvement in overall survival (primary endpoint) at a pre-specified interim analysis, plus statistically significant improvements in PFS and ORR versus durvalumab alone. No hazard ratios, medians, or response rates have been disclosed yet; full data will be presented at an upcoming medical congress and shared with regulators.
First Phase 3 BiTE OS benefit in 1L maintenance ES-SCLCSource: Amgen press release, Sept 8, 2026
Safety
Per the topline announcement, the combination’s safety profile was consistent with the known profiles of the individual medicines, with no new or unexpected safety signals. The trial design used post-infusion monitoring of 1–2 hours (6–8 hours in certain regions including Europe) on Cycle 1 Day 1 and Day 8 — shorter than the 22–24 hour monitoring in tarlatamab’s current second-line US label. Quantitative safety data (CRS/ICANS rates, discontinuations) have not yet been disclosed.
Source: Amgen press release, Sept 8, 2026Clinical Implications
⚠ Investigational in 1L maintenance: the combination is not approved in this setting; Amgen will engage regulators with the interim data. ✅ Tarlatamab is already a fully FDA-approved, NCCN Category 1 preferred standard in 2L+ ES-SCLC (DeLLphi-304: OS 13.6 vs 8.3 months, HR 0.60). If registered on DeLLphi-305, DLL3-targeted BiTE therapy would move a line earlier — changing 1L maintenance from passive checkpoint continuation to active immune redirection, with the rest of the DeLLphi program (306 in LS-SCLC, 312 in 1L induction+maintenance) testing even earlier use.
Source: Amgen, full approval (DeLLphi-304), Nov 19, 2025DeLLphi-305 in the News
DeLLphi-305 FAQ
What is the DeLLphi-305 trial?
DeLLphi-305 (NCT06211036) is a global, randomized, open-label Phase 3 trial testing tarlatamab (IMDELLTRA, Amgen) plus durvalumab (Imfinzi, AstraZeneca) versus durvalumab alone as first-line maintenance treatment for extensive-stage small cell lung cancer (ES-SCLC) in patients whose disease had not progressed after initial treatment with durvalumab, platinum-based chemotherapy and etoposide. 563 patients were randomized 1:1. The primary endpoint is overall survival; secondary endpoints include PFS, ORR, DCR, DoR, TTP, safety and quality of life.
What did the DeLLphi-305 topline results show?
Per Amgen's September 8, 2026 announcement, the study met its primary endpoint at a pre-specified interim analysis: tarlatamab plus durvalumab demonstrated a statistically significant and clinically meaningful improvement in overall survival versus durvalumab alone, with statistically significant improvements also in progression-free survival and objective response rate. Numeric results (hazard ratios, medians) have not yet been disclosed; detailed data will be presented at an upcoming medical congress. It is the first Phase 3 study of a bispecific T-cell engager to show an overall survival benefit in the first-line maintenance setting for ES-SCLC.
Is tarlatamab plus durvalumab FDA approved for first-line ES-SCLC?
No. The first-line maintenance combination is investigational. Tarlatamab (IMDELLTRA) itself holds full FDA approval (granted November 19, 2025, converting the May 2024 accelerated approval) for ES-SCLC with disease progression on or after platinum-based chemotherapy, based on the DeLLphi-304 trial, and is the NCCN Category 1 preferred option in that second-line setting. Amgen plans to share the DeLLphi-305 data with regulators.
How is tarlatamab given in DeLLphi-305, and what about safety monitoring?
Tarlatamab was given IV every two weeks with durvalumab IV every four weeks, continuing until progression or unacceptable toxicity. Per Amgen, the combination's safety profile was consistent with the known profiles of each medicine with no new or unexpected safety signals; the study design included healthcare-setting monitoring for 1 to 2 hours (6 to 8 hours in certain regions, including Europe) after tarlatamab infusion on Cycle 1 Day 1 and Day 8 - notably shorter than the 22-24 hour monitoring in the current second-line label.
Why does DeLLphi-305 matter for small cell lung cancer?
ES-SCLC almost always relapses after first-line chemo-immunotherapy, and survival gains in the frontline setting have been rare and incremental. DeLLphi-305 is the first Phase 3 trial to show that adding a DLL3-targeted bispecific T-cell engager during maintenance extends overall survival before relapse occurs - physicians on this page called it a landmark and a potential new chapter for 1L maintenance therapy, building on the Phase 1b DeLLphi-303 experience (median OS 25.3 months at WCLC 2025, reported separately).