Top KOLs Discussing DeLLphi-305
DeLLphi-305 Key Slides & Visuals
DeLLphi-305 Top Tweets
𝕏📣 Changes and progress for tarlatamab in SCLC! ✅ FDA has approved REDUCED monitoring time for the first two doses: 22–24h on C1D1 and C1D8 ➡️ 6–8h. Easing this lowers a key barrier to outpatient and community administration. 🔜 Coming soon: positive overall survival results from the phase III maintenance DeLLphi-305 trial ➡️ soon moving into 1L. 📄 To help teams operationalize all of this, our recent multi-institutional perspective on tarlatamab administration and management of CRS/ICANS provides practical, real-world guidance for safe delivery. 👀 Stay tuned for outpatient-focused delivery and risk management strategies. https://t.co/zXL70ok6Gj @BZhangMD @ADesaiMD @alissajcooper @MehmetAltanMD @Annechiangmd @LaurenByersMD @Sonampuri
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 tarlatamab’s US label originally required. On September 11, 2026 (BLA 761344/S-002) the FDA reduced the label’s routine monitoring for Cycle 1 Day 1 and Day 8 to 6–8 hours, with patients remaining within 1 hour of an appropriate healthcare setting for 48 hours total; 22–24-hour monitoring is retained after certain Grade ≥2 CRS/ICANS events (FDA label, Sept 2026). Quantitative safety data (CRS/ICANS rates, discontinuations) have not yet been disclosed. Source: IMDELLTRA USPI s002 (Sept 11, 2026) →
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
WCLC 2026: Live KOL Reaction
Physician posts about this trial captured live during the IASLC 2026 World Conference on Lung Cancer (Seoul, September 12–15). Quotes are verbatim; each card links to the original post. Last updated 2026-09-22.
📣 Big news in Small Cell Lung Cancer! #DeLLphi305, a Phase 3 study of #tarlatamab maintenance with chemo-IO + durvalumab in #SCLC 🫁, met its primary endpoint. Bringing tarlatamab to the frontline could improve survival in a disease long marked by therapeutic nihilism. ❓🙋🏽♀️how to improve access and ease of administration ( check out #WCLC26 abstract ) ❓how to improve patient selection and minimize toxicity
Thank you Dr. Anne Chiang @Annechiangmd @YaleCancer here at @IASLC #WCLC26 for highlighting our recent biomarker research on durable responders of lurbinectedin that identified ISL1 dependency as a novel neuroendocrine subtype in SCLC that predicts response, published in @MCT_AACR. Given the following growing evidence: 1) the press release with positive OS outcomes with DeLLphi-305 in the 1LM 2) negative confirmatory study with LAGOON (although multiple study design concerns existed, including pts with hx of tx brain mets) 3) sponsor withdrawal of lurbinectedin in the relapsed/refractory setting of ES-SCLC 4) risk for relapsed SCLC treatment gap while awaiting ADC approvals that are limited by ILD, myelosuppression, GI toxicity and acquired resistance development. … the prospective need to apply proposed biomarkers like ISL1 is important to understand who ultimately will benefit from lurbinectedin in their treatment of SCLC. @SclcSMASHERS @LUNGevity @lungoncdoc @weldeiry @OTtheScientist @PareshKumaaar @ktgminton @IUCancerCenter @MoffittNews @OncLive @OncoAlert @oncodaily @LungCancerRx @triparnasen @AparGanti @StephenVLiu
🚨 DeLLphi-305 is positive! Tarlatamab + durvalumab as 1L maintenance in ES-SCLC significantly improved: 🫁 OS (primary endpoint) 📈 PFS 🎯 ORR vs durvalumab alone, with no new safety signals. 🔥 First Phase 3 BiTE study to show an OS benefit in 1L maintenance ES-SCLC. 🔗 https://t.co/y9NRAeMirT
🔥DeLLphi-305: "Statistically significant and highly clinically meaningful improvement in overall survival (OS)" 🆙 @Amgen @AstraZeneca 👥Patients: Extensive-stage small cell lung cancer (ES-SCLC), no progression after 1st-line induction with durvalumab + platinum chemotherapy + etoposide 3⃣Phase III ⚖️Tarlatamab + durvalumab ⚖️Durvalumab alone 🔢NCT06211036 #LCSM @OncoAlert @Larvol 🔗 https://t.co/4tFnvnm3UA 🔗 https://t.co/rhf7IGZ1lN
TWO IOs. TWO MAINTENANCE STRATEGIES. ES-SCLC maintenance is evolving. IMforte: Atezolizumab → add lurbinectedin DeLLphi-305: Durvalumab → add tarlatamab Different IO backbones. Different maintenance partners. Different biology. But one emerging strategy: don’t wait for relapse — intensify while the disease is still controlled. Is maintenance becoming the new battleground in ES-SCLC? Cross-trial comparison is conceptual; these strategies were not directly compared. #MVOnco #SCLC #ES_SCLC #IMforte #DeLLphi305 #Lurbinectedin #Tarlatamab #LungCancer #ThoracicOncology
Very excited to see the full dataset - addition of tarlatamab as first-line maintenance therapy to ES-SCLC in DeLLphi-305 improves PFS and OS. Focus now has to be on implementation, patient selection, and removing barriers. https://t.co/l02noCZ3G5
🚨 DeLLphi-305: Tarlatamab enters 1L maintenance in ES-SCLC Who was treated? Patients with extensive-stage SCLC who had not progressed after platinum + etoposide + durvalumab. Phase 3 design 563 patients randomized 1:1: Tarlatamab + durvalumab vs Durvalumab alone Primary endpoint: OS Key secondary endpoints: PFS, ORR What was announced? ✅ Statistically significant and clinically meaningful OS benefit ✅ Significant improvement in PFS ✅ Significant improvement in ORR ✅ No new unexpected safety signals reported Why it matters This is the first Phase 3 study of a BiTE therapy to demonstrate an OS benefit in first-line maintenance ES-SCLC. That is a major milestone in a disease where many patients relapse early and never reach second-line therapy. But we still need the numbers • OS hazard ratio • Median OS • Median PFS • Detailed CRS/ICANS rates • Discontinuation and treatment-related mortality data Clinical verdict 🔥 Potentially practice-changing. If the magnitude of OS benefit is substantial and toxicity remains manageable, tarlatamab + durvalumab could become a new first-line maintenance standard in ES-SCLC. #SCLC #LungCancer #Oncology @ASCO @oncoalert
Potentially practice-changing phase III news in extensive-stage small cell lung cancer. * In DeLLphi-305, adding the DLL3xCD3 T-cell engager tarlatamab to durvalumab maintenance after platinum/etoposide + durvalumab significantly improved overall survival and progression-free survival versus durvalumab alone. Interesting to see T-cell engagers moving earlier in treatment, rather than being reserved for relapse. For now, these are topline results from a company announcement, so the actual hazard ratios, survival curves, and detailed safety data will matter. Looking forward to seeing the full results.
A great day for our patients and the entire #SCLC community! 👏👏👏 Thrilled to see the positive results from DeLLphi-305. A landmark achievement in #SCLC! 🎉 https://t.co/DVDlycnuQC
Visual summary of today’s phase 3 DeLLphi-305 update in ES-SCLC: tarlatamab + durvalumab maintenance improved OS vs durvalumab alone after induction durvalumab + platinum/etoposide. PFS and ORR also positive. Full data still needed. #SCLC #LCSM https://t.co/pyeQbPyoRc
🚨 Too much oncology news. Too little time. That’s where the @OncoAlert Newsletter really delivers value: filtering the noise and surfacing the data most worth knowing each week. This edition brings together: 🔴 LUNG: DeLLphi-305 with tarlatamab + durvalumab in ES-SCLC, plus new data on lazertinib resistance/ctDNA clearance and osimertinib in uncommon EGFR mutations 🟠 GI: early Phase 1 data with L-glutamine + gemcitabine/nab-paclitaxel in advanced pancreatic cancer 🔵 GU: perioperative strategies in high-risk #ProstateCancer and fracture risk with abiraterone 🟣 BREAST: pCR with neoadjuvant THP in HER2+ disease and biomarkers in stage I TNBC 🌍 And this week also features AcuVox — helping colleagues track the trials, treatments, and topics generating the most attention at major cancer congresses. What I value most is the format: high-yield, clinically relevant, and easy to scan in minutes. 👉 REGISTER TO GET IT: https://t.co/NFi1ia6FQt Stay informed. Focus on what matters. @matteolambe @aftimosp @E_de_Azambuja @DrSGraff @ErikaHamilton9 @double_whammied @maryam_lustberg @raalbany @hoperugo @stolaney1 @LoiSher @JaniceTNBCmets @montypal @DrDanielHeng @apolo_andrea @DrChoueiri @PGrivasMDPhD @TiansterZhang @neerajaiims @amerseburger @sonpavde @drenriquegrande @tompowles1 @cdanicas @nataliagandur @realbowtiedoc @Onco_Cifu88 @scocmem @FernandoOnco @ElisaAgostinett @to_be_elizabeth @Erman_Akkus @MarioBalsaMD @DrMirallas @GIMedOnc @UOzkerim @DrRishabhOnco @PaulJiL @DaisukeKotani @DraMartinezLago @p_ciracimd @BenWestphalen @CentralParkWMD @graokane @amandaNizamMD @DrVilmaPBarcia #OncoAlert #Oncology #CancerResearch #LungCancer #BreastCancer #ProstateCancer #PancreaticCancer
JUST OUT 🚨 DeLLphi-305 Update in #SCLC 🫁 To Be Presented Soon! Ping @COR2EDMedEd @gotoPER @mirrorsmed @VJOncology @high5md https://t.co/er7POxdu3m
🌟Time to move T-cell engagers to 1st-L maintenance ? A new era is dawning for our patients with #SCLC The much-awaited press-release from DeLLphi-305 confirms that analysis has demonstrated a statistically significant and clinically meaningful improvement in overall survival with tarlatamab in combination with durvalumab compared to durvalumab alone. Full data coming soon! https://t.co/IQnZmYfSuh @SclcSMASHERS @myESMO @IASLC @ASCO @LungCancerEu @OncoAlert @OncBrothers @YoungLungCancer @lcrf_org @PeerView @oncodaily
DeLLphi-305 met its overall-survival endpoint in 1L ES-SCLC maintenance. Full read: https://t.co/wbcDvWKbYi https://t.co/5l6H3fhneX
🔬 DeLLphi-305 data show tarlatamab plus durvalumab significantly improved overall survival as first-line maintenance in extensive stage small cell #LungCancer. Read more: https://t.co/UEmrS0Tcti #SCLC #Oncology #ThoracicOncology #ClinicalTrials #CancerTreatment
DeLLphi-305 — A Phase III study comparing tarlatamab + durvalumab versus durvalumab alone after chemo-IO in ES-SCLC. Per the press release, the study delivered a highly significant and clinically meaningful overall survival benefit with tarlatamab + durvalumab versus durvalumab. A big win and a major milestone for the field of lung cancer #LCSM @OncoAlert https://t.co/wXZq6IxKoS
Phase III DeLLphi-305 met its primary endpoint at interim analysis: @Amgen's Imdelltra (tarlatamab-dlle) with @AstraZeneca's Imfinzi (durvalumab) significantly improved overall survival versus durvalumab alone. https://t.co/YD4eIALIKr #Oncology #ClinicalTrials
@care_natureme @OncLive @drshieldsmd @IUCancerCenter Considering the potential introduction of #tarlatamab in the 1lm, what would be the optimal treatment regimen—particularly regarding the best use of all available therapeutic options (which are limited)? 1. #Imforte in 1lm + Tarla in 2l 2. #DeLLphi-305 in 1lm + Topotecan in 2l
🚨Oncology Breakthrough | Can a new combination change the first-line treatment landscape for extensive-stage small cell lung cancer? Phase 3 DeLLphi-305 showed that #tarlatamab-dlle (#IMDELLTRA, Amgen) + #durvalumab (#IMFINZI, AstraZeneca) significantly improved overall survival versus durvalumab alone in the first-line maintenance setting. The combination also improved progression-free survival (PFS) and objective response rate (ORR), marking the first Phase 3 study of a BiTE® therapy to demonstrate an overall survival benefit in this setting. 📰Read more: https://t.co/reOrh9YJJi #SCLC #SmallCellLungCancer #LungCancer #Oncology #CancerResearch #Immunotherapy
Clinical Intelligence | Amgen: IMDELLTRA Imfinzi Combination Delivers Landmark Survival Gain in DeLLphi-305 Trial Full data analysis on BiotechReality: https://t.co/zOsmnF0RCl #Amgen #AstraZeneca #IMDELLTRA #Tarlatamab #Imfinzi #Durvalumab #DeLLphi305 #Phase3Trial #SCLC
1/5 Amgen says tarlatamab plus durvalumab improved overall survival versus durvalumab alone in first-line extensive stage small cell lung cancer. Phase 3, DeLLphi-305. If it holds up at full presentation, it is the first T-cell engager to win on OS in frontline lung.
First OS win for a T-cell engager in first-line ES-SCLC maintenance: phase 3 DeLLphi-305, 563 randomized, primary endpoint met at a prespecified interim analysis. No median, no hazard ratio, no event count, no data cutoff. #LungCancer #ClinicalTrials https://t.co/pWKgfWSQM4
In late-stage trial results, AstraZeneca’s block-buster cancer drug Imfinzi, combined with Amgen’s targeted immunotherapy Imdelltra, demonstrated a landmark, statistically significant improvement in overall survival for patients with first-line extensive-stage small cell lung cancer. The Phase III DeLLphi-305 study tested this combo therapy as a maintenance treatment following standard chemotherapy. Results showed that the dual-action regimen significantly prolonged patient lives while boosting progression-free survival compared to Imfinzi alone. Crucially, no new safety concerns emerged. Given the historically low survival rates associated with aggressive lung cancers, this break-through marks a pivotal clinical milestone that provides fresh hope to millions worldwide.
Amgen 8 Sep: DeLLphi-305 topline — tarlatamab + durvalumab beat durvalumab on OS as 1L ES-SCLC maintenance. No numbers. Not a CHMP opinion. EU Imdylltra stays later-line monotherapy.
A striking timeline in ES-SCLC: 💉 Early 1980s: Platinum–etoposide ⏳ ~4 decades... ✨ 2018–2019: IMpower133 / CASPIAN ⌛️ only ~7–8 years 🔥 2026: DeLLphi-305 — tarlatamab + durvalumab maintenance The pace of progress in SCLC is accelerating!🚀 https://t.co/o8zZAoh6Oc
1/3 Big news in #SCLC today. Phase III DeLLphi-305: tarlatamab + durvalumab maintenance improved OS vs durvalumab alone after first-line platinum/etoposide + durvalumab in ES-SCLC. PFS and ORR also positive. Very encouraging—full data will matter.
A NEW MAINTENANCE ERA IN ES-SCLC? DeLLphi-305 brings tarlatamab earlier in the treatment journey. After platinum–etoposide + durvalumab induction, patients without progression were randomized to durvalumab alone vs tarlatamab + durvalumab maintenance. The topline result: OS improved — with PFS and ORR improving too. The key shift? Don’t wait for relapse. Target residual disease during 1L maintenance. Full numerical data awaited. #MVOnco #DeLLphi305 #Tarlatamab #SCLC #LungCancer #ThoracicOncology #MedicalOncology
MERLIN, Tarlatamab treatment for limited small cell lung cancer in patients in maintenance; a phase II clinical trial in progress. WORLD CONFERENCE ON LUNG CANCER 2026 SEOUL @gecp_org @Hospital_FJD @quironsalud @UAM_Madrid #IIS-FJD @OncoAlert @AEACaP #LCSM #WCLC26 @SCLC https://t.co/lzb9Zxatfl
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 the second-line label originally required. On September 11, 2026 the FDA reduced the label's routine monitoring for Cycle 1 Day 1 and Day 8 to 6-8 hours (patients remain within 1 hour of a healthcare setting for 48 hours total; 22-24 hour monitoring is retained after certain Grade 2 or higher CRS/ICANS events).
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).