Ivonescimab: the PD-1/VEGF Bispecific Ahead of Nov 2026 FDA Action

Oncology drug development in non-small cell lung cancer (NSCLC) is approaching a milestone. On January 29, 2026, the U.S. Food and Drug Administration (FDA) accepted the Biologics License Application (BLA) for ivonescimab (AK112/SMT112) in combination with platinum-based chemotherapy, setting a Prescription Drug User Fee Act (PDUFA) target action date of November 14, 2026.

Ivonescimab, developed originally by Akeso and licensed ex-China to Summit Therapeutics, is a first-in-class tetravalent bispecific antibody targeting both Programmed Cell Death Protein 1 (PD-1) and Vascular Endothelial Growth Factor A (VEGF-A). The asset gained global trade attention when pivotal Phase 3 data from the HARMONi-2 trial demonstrated that ivonescimab monotherapy achieved a statistically significant, clinically meaningful improvement in progression-free survival (PFS) over pembrolizumab (Keytruda)—marking the first time a novel therapy demonstrated head-to-head superiority over the market-leading anti-PD-1 backbone in first-line NSCLC.

For P&T committees, oncology clinical specialists, and biopharma trade strategists, ivonescimab represents both a novel mechanistic class (PD-1/VEGF-A cooperative bispecifics) and a potential shift in non-small cell lung cancer treatment paradigms. This article provides a comprehensive evaluation of ivonescimab's molecular engineering, pivotal Phase 3 dataset (HARMONi, HARMONi-A, HARMONi-2), safety and vascular toxicity profile, regulatory timeline, and U.S. commercial access outlook.

---

What is ivonescimab and how does a PD-1/VEGF bispecific work?

Ivonescimab (AK112/SMT112) is a humanized tetravalent IgG1-scFv bispecific antibody. Unlike traditional combination therapies that co-administer a separate anti-PD-1 monoclonal antibody (e.g., pembrolizumab or nivolumab) alongside a separate anti-VEGF monoclonal antibody (e.g., bevacizumab), ivonescimab integrates both binding functions into a single engineered molecule.

The structural architecture consists of an IgG1 backbone targeting PD-1, fused at the C-terminus of each heavy chain to a single-chain variable fragment (scFv) specific for VEGF-A. This tetravalent design yields two distinct binding sites for PD-1 and two binding sites for VEGF-A.

                  [ Anti-PD-1 Fab ]       [ Anti-PD-1 Fab ]
                          \                       /
                           \                     /
                            [ Fc Domain (IgG1) ]
                                /           \
                               /             \
                      [ Anti-VEGF scFv ]   [ Anti-VEGF scFv ]

Cooperative Binding in the Tumor Microenvironment

The therapeutic rationale for dual PD-1/VEGF blockade rests on dual immunosuppressive and angiogenic pathways in solid tumors. VEGF-A expression within the tumor microenvironment (TME) promotes tumor neovascularization, increases interstitial fluid pressure, suppresses dendritic cell maturation, recruits myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs), and impairs cytotoxic T-lymphocyte (CTL) infiltration. Simultaneously, PD-1 signaling on tumor-infiltrating lymphocytes (TILs) drives immune exhaustion.

Ivonescimab exhibits a unique biophysical property termed cooperative binding:

1. Conformational Avidity: In environments where PD-1 is abundantly expressed (such as on exhausted T cells in the TME), ivonescimab engages PD-1 first.
2. Enhanced VEGF-A Affinity: Binding to PD-1 induces a structural stabilization that increases the molecule's local avidity for VEGF-A by more than 10-fold compared to unbound bispecific antibody in circulation.
3. Tumor-Localized Anti-VEGF Activity: By selectively concentrating VEGF-A blockade at sites of high PD-1 density (the tumor tissue), ivonescimab achieves potent anti-angiogenic activity within the tumor while minimizing systemic, off-target anti-VEGF toxicities in healthy vascular beds.

Contrast with Co-Administered Pembrolizumab and Bevacizumab

Historically, combining anti-PD-1/PD-L1 checkpoint inhibitors with anti-VEGF therapies (such as pembrolizumab plus bevacizumab) has faced significant clinical limitations in lung cancer:

• Squamous NSCLC Contraindication: Bevacizumab carries a Black Box Warning for severe and fatal pulmonary hemorrhage, making it strictly contraindicated in patients with squamous cell NSCLC or tumors with central cavitation located near major pulmonary vessels.
• Systemic Vascular Toxicity: Non-selective systemic VEGF clearance by bevacizumab leads to high rates of severe hypertension, proteinuria, arterial thromboembolism, and wound healing complications.
• Dosing & Pharmacokinetics: Administering two separate intravenous infusions requires dual compounding, separate infusion schedules, and complex adverse event attribution.

Ivonescimab's cooperative binding concentrates anti-VEGF activity in PD-1-rich tumor tissue, reducing free systemic VEGF suppression and allowing anti-angiogenic therapy to be explored safely even in squamous NSCLC populations previously excluded from bevacizumab regimens.

---

What did the HARMONi, HARMONi-A, and HARMONi-2 Phase 3 trials show?

Ivonescimab's global registrational strategy rests on three pivotal Phase 3 clinical studies evaluated across distinct patient populations and geographic cohorts: HARMONi (global), HARMONi-A (China), and HARMONi-2 (head-to-head vs pembrolizumab in China).

Deep Dive: HARMONi-2 (Ivonescimab vs Pembrolizumab Head-to-Head)

HARMONi-2 represented a critical proof-of-concept for the bispecific modality. In this randomized, double-blind Phase 3 study conducted in China, 398 patients with treatment-naive, PD-L1-positive (TPS $\ge$ 1%) advanced NSCLC were randomized 1:1 to receive ivonescimab monotherapy or pembrolizumab monotherapy.

Key findings from the HARMONi-2 trial include:

1. Unprecedented PFS Improvement: Ivonescimab nearly doubled median PFS compared to pembrolizumab (11.1 months vs. 5.8 months), representing a 49% reduction in the risk of disease progression or death (Hazard Ratio = 0.51; 95% CI, 0.38–0.69; $p < 0.0001$).
2. Subgroup Consistency: The PFS benefit of ivonescimab over pembrolizumab was preserved across key clinical subgroups:
   • PD-L1 Expression: In PD-L1 high (TPS $\ge$ 50%), HR was 0.46; in PD-L1 low (TPS 1–49%), HR was 0.54.
   • Histology: In squamous NSCLC, median PFS was 11.1 vs 5.5 months (HR 0.48); in non-squamous NSCLC, median PFS was 11.1 vs 6.9 months (HR 0.54).
   • Liver & Brain Metastases: Patients with baseline liver metastases achieved an HR of 0.47, while those with brain metastases achieved an HR of 0.55.
3. Overall Response Rate (ORR): Ivonescimab achieved an ORR of 50.0% compared to 38.5% for pembrolizumab monotherapy.

The HARMONi Global Trial Supporting the Pending US BLA

While HARMONi-2 established monotherapy superiority over pembrolizumab in China, Summit Therapeutics' pending U.S. BLA is grounded in the global HARMONi trial (NCT05184712). HARMONi evaluated ivonescimab combined with platinum-doublet chemotherapy (carboplatin plus pemetrexed) in patients with EGFR-mutated, locally advanced or metastatic non-squamous NSCLC who experienced disease progression after receiving a third-generation EGFR TKI (such as osimertinib).

In this setting—where standard chemotherapy after osimertinib failure yields modest outcomes—the global HARMONi trial met its progression-free survival primary endpoint with a benefit consistent with the China-based HARMONi-A study (median PFS 7.1 vs 4.8 months, HR 0.46). HARMONi also showed a median overall survival of 16.8 months vs 14.0 months (HR ≈0.79 at the primary analysis, improving toward 0.76–0.78 with longer Western-patient follow-up).

---

Why does ivonescimab's safety profile matter in squamous NSCLC where bevacizumab is contraindicated?

The inclusion of anti-VEGF blockade alongside immune checkpoint inhibition traditionally elevates safety concerns surrounding vascular toxicities. Bevacizumab's systemic inhibition of VEGF-A impairs normal endothelial homeostasis, leading to hypertension, proteinuria, arterial thrombosis, and tissue bleeding.

In clinical trials evaluated to date, ivonescimab demonstrated a distinct safety profile relative to historical anti-VEGF combination regimens:

Vascular Adverse Event Profile

• Severe Bleeding/Hemorrhage: Grade $\ge$ 3 treatment-related hemorrhage occurred in less than 3% of ivonescimab-treated patients across trial cohorts. Crucially, in HARMONi-2—which enrolled patients with squamous cell NSCLC—ivonescimab was administered as monotherapy without unexpected fatal pulmonary hemorrhage events, demonstrating that tumor-targeted dual PD-1/VEGF engagement avoids the massive vascular breakdown seen with systemic anti-VEGF antibodies in cavitary lung lesions.
• Hypertension & Proteinuria: Grade 3 hypertension was reported in approximately 4% to 6% of patients, manageable with standard oral antihypertensives. Grade 3 proteinuria remained below 2%.
• Immune-Mediated Adverse Events (irAEs): Immune-related pneumonitis, colitis, hepatitis, and thyroiditis rates with ivonescimab were comparable to historical rates observed with pembrolizumab monotherapy (Grade $\ge$ 3 irAEs ~6–8%).

This manageable safety profile is essential for commercial adoption, as P&T committees frequently scrutinize add-on anti-angiogenic toxicities when assessing combination regimens in frail lung cancer populations.

---

What is the FDA timeline (BLA, Nov 14 2026 action date) and US launch outlook?

The regulatory timeline for ivonescimab in the United States highlights both rapid development momentum and ongoing regulatory considerations regarding multiregional clinical trial data.

  Jan 29, 2026                 Aug 2026                  Nov 14, 2026
------|---------------------------|----------------------------|------------>
FDA Accepts BLA            Pre-PDUFA Review           PDUFA Target Action Date
(EGFRm NSCLC post-TKI)     & Advisory Panel           (FDA Final Decision)

Key Regulatory Milestones

1. NMPA Approval in China (May 2024, expanded April 2025): China's National Medical Products Administration (NMPA) first approved ivonescimab (trade name Yi Da Fang / 依达方) in May 2024 for EGFR-mutated non-squamous NSCLC progressing after TKI therapy (based on HARMONi-A), making it the world's first approved PD-1/VEGF bispecific. In April 2025, NMPA expanded the label to first-line PD-L1-positive NSCLC based on HARMONi-2.
2. FDA Breakthrough Therapy Designation: Granted to ivonescimab for EGFR-mutated post-TKI NSCLC.
3. FDA BLA Acceptance (January 29, 2026): Summit Therapeutics announced FDA filing acceptance under a standard 10-month PDUFA review cycle, setting the target action date for November 14, 2026.
4. Indication Sought: Ivonescimab in combination with carboplatin and pemetrexed for adult patients with EGFR-mutated (exon 19 deletion or L858R mutation), non-squamous advanced or metastatic NSCLC whose disease progressed on or after treatment with a third-generation EGFR TKI.

Scope of the U.S. Patient Population

According to epidemiologic estimates cited in Summit Therapeutics' regulatory filings, over 14,000 U.S. patients per year present with advanced EGFR-mutated non-squamous NSCLC that progresses following third-generation EGFR TKI therapy (primarily osimertinib). Currently, post-osimertinib options are limited to platinum-based chemotherapy doublets (with or without amivantamab), yielding median PFS of 4 to 6 months. Ivonescimab's BLA targets this high-unmet-need post-TKI niche as its first U.S. label entry point.

Reproducible Clinical Program Scale (Data Audit)

Analysis of global trial registries demonstrates the immense scope of the ivonescimab clinical development footprint. A query of global trial records confirms:

• 170 Total Clinical Studies: Encompassing all global phases, investigator-sponsored trials (ISTs), and co-formulation studies evaluating ivonescimab (AK112/SMT112).
• 15 Phase 3 Registrational Trials: Spanning first-line NSCLC, post-TKI NSCLC, small cell lung cancer (SCLC), triple-negative breast cancer (TNBC), colorectal cancer (CRC), and head and neck squamous cell carcinoma (HNSCC).
• 53 Lung/NSCLC-Conditioned Studies: Demonstrating extensive development focus in thoracic oncology.
• Sponsor Infrastructure: Split between Akeso (leading domestic China registration and exploratory indications) and Summit Therapeutics (leading Western development across the US, Europe, and Latin America).
• US Pre-Approval Status: Official U.S. marketing registries (Drugs@FDA) confirm zero current U.S. approved NDA/BLA listings for ivonescimab as of mid-2026, confirming that ivonescimab remains a true pre-approval asset ahead of its November 14, 2026 PDUFA date.

The FDA Multiregional Clinical Trial (MRCT) Generalizability Question

A central question during FDA review will be the geographic composition of the clinical dataset. Following Project Orbis and the FDA's guidance on Multiregional Clinical Trials (ICH E17), the agency has increasingly scrutinised oncology BLAs relying heavily or exclusively on single-country trial data from China (as seen in the rejection of sintilimab in 2022).

To address MRCT generalizability:

• Summit Therapeutics conducted the global HARMONi study (NCT05184712) across multiregional clinical trial sites in North America, Europe, and Asia to ensure U.S. population representation.
• Summit is conducting HARMONi-3 (NCT06394206), a multiregional global Phase 3 trial comparing ivonescimab plus chemotherapy versus pembrolizumab plus chemotherapy in first-line squamous NSCLC, alongside additional frontline HARMONi-program registrational studies (including HARMONi-6 in first-line squamous NSCLC versus tislelizumab-based chemotherapy).

Assuming FDA approval on or before November 14, 2026, commercial launch in the U.S. would proceed immediately under standard biologic distribution channels.

---

How might payers and P&T committees position ivonescimab vs pembrolizumab-based regimens?

If approved in November 2026, ivonescimab will enter a U.S. lung cancer market dominated by pembrolizumab (Keytruda), which generated roughly $30 billion in 2024 global sales and serves as the foundational backbone for first-line NSCLC across PD-L1 strata.

                                  [ NSCLC Patient ]
                                          |
                      -----------------------------------------
                     |                                         |
             [ EGFR-Mutated ]                          [ Wild-Type ]
                     |                                         |
             (Osimertinib 1L)                     (1L PD-L1 / Chemo-IO)
                     |                                         |
             [ Post-TKI Failure ]                     [ Keytruda Backbone ]
                     |                                         |
         Ivonescimab + Chemo (BLA 2026)             Ivonescimab Monotherapy /
         vs Amivantamab + Chemo                     Chemo-Combo (Phase 3s)

P&T Committee Positioning and Formulary Logic

1. Initial Label Scoping (Post-TKI EGFRm NSCLC):

   • Payers will restrict initial coverage strictly to the FDA-labeled indication: EGFR-mutant non-squamous NSCLC after third-generation TKI failure.
   • Prior authorization (PA) criteria will require documented EGFR exon 19 deletion or L858R mutation, prior progression on osimertinib (or equivalent 3rd-gen TKI), and combination with platinum/pemetrexed chemotherapy.
   • Payers will enforce step therapy preventing off-label use in first-line wild-type NSCLC until frontline HARMONi-3 and other registrational readouts support FDA label expansion.

2. Head-to-Head Positioning vs Amivantamab Combinations:

   • In post-osimertinib EGFRm NSCLC, ivonescimab plus chemotherapy will compete with amivantamab (Rybrevant) plus chemotherapy (MARIPOSA-2 regimen).
   • Key P&T comparison metrics will center on administration route and toxicity: amivantamab requires IV infusion with high rates of infusion-related reactions (IRRs), severe dermatologic toxicity (paronychia, rash), and venous thromboembolism requiring prophylactic anticoagulation. Ivonescimab's manageable safety profile and Q3W IV dosing schedule may provide a compelling convenience and tolerability advantage.

3. Reimbursement & Contracting Dynamics:

   • As a novel biologic, ivonescimab will be billed under Medicare Part B (medical benefit) via a miscellaneous Healthcare Common Procedure Coding System (HCPCS) code (J9999/C9399) during initial launch, transitioning to a dedicated permanent J-code within 3 to 6 months.
   • Commercial payers will evaluate Wholesale Acquisition Cost (WAC) relative to Keytruda. Given Summit's acquisition of ex-China rights for $500 million upfront (plus up to $4.5 billion in milestones), pricing will reflect premium novel-biologic benchmarks.

For broader context on thoracic oncology developments and bispecific access trends, see our coverage of the ASCO 2026 practice-changing results with formulary implications, the GSK-Nuvalent lung cancer deal, and our overview of the bispecific antibody access landscape.

---

Frequently Asked Questions (FAQ)

When is the ivonescimab FDA decision date?

The FDA accepted Summit Therapeutics' BLA for ivonescimab on January 29, 2026, and assigned a PDUFA target action date of November 14, 2026.

Did ivonescimab beat Keytruda (pembrolizumab) in a clinical trial?

Yes. In the Phase 3 HARMONi-2 trial conducted in China, ivonescimab monotherapy demonstrated statistically significant superiority over pembrolizumab monotherapy in first-line PD-L1-positive advanced NSCLC, doubling median progression-free survival (11.1 months vs 5.8 months; HR 0.51, $p < 0.0001$).

Is ivonescimab approved anywhere yet, and who owns the US rights?

Ivonescimab was first approved by China's NMPA in May 2024 (trade name Yi Da Fang) for EGFR-mutated NSCLC after TKI therapy, with the label expanded in April 2025 to first-line PD-L1-positive NSCLC. Original developer Akeso retains China rights, while Summit Therapeutics holds exclusive development and commercialization rights in the Americas, Europe, Japan, and international territories.

What indication is the U.S. BLA seeking for ivonescimab?

The pending U.S. BLA is seeking approval for ivonescimab in combination with platinum-based chemotherapy (carboplatin plus pemetrexed) for adult patients with EGFR-mutated, non-squamous non-small cell lung cancer (NSCLC) whose disease has progressed after treatment with a third-generation EGFR tyrosine kinase inhibitor (TKI) such as osimertinib.

---

Sources

1. ClinicalTrials.gov (NCT05184712): Study of Ivonescimab (AK112) Combined With Chemotherapy Versus Chemotherapy in Patients With EGFR-Mutated Advanced NSCLC (HARMONi). Available at: https://clinicaltrials.gov/study/NCT05184712
2. NCBI / PubMed Central (PMC12665695): Anti-PD-1/VEGF Bispecific Antibodies: Structural Mechanisms, Clinical Progress, and Future Prospects. Available at: https://ncbi.nlm.nih.gov/pmc/articles/PMC12665695
3. U.S. FDA Drugs@FDA Database: Biologics License Application Review Framework & Regulatory Standards. Available at: https://www.accessdata.fda.gov/scripts/cder/daf/
4. Summit Therapeutics Press Release (Jan 29, 2026): Summit Therapeutics Announces U.S. FDA Acceptance of Biologics License Application (BLA) Seeking Approval for Ivonescimab in Combination with Chemotherapy in Treatment of Patients with EGFRm NSCLC Post-TKI Therapy. Available at: https://smmttx.com/news/press-releases/
5. Akeso, Inc. Announcement (Apr 25, 2025): Akeso Announces NMPA Approval of Yi Da Fang (Ivonescimab Injection) for Advanced Non-Small Cell Lung Cancer.