First-line Advanced/Metastatic Squamous NSCLC: HARMONi-6 based Treatment Selection

Authored by Open Medicine, published on 2026-06-07 12:19:05.0

The algorithm is broadly aligned with current first-line management of advanced/metastatic squamous NSCLC: universal biomarker testing, PD-L1–informed selection, and chemoimmunotherapy as the dominant standard for most patients without actionable drivers. The emphasis on intensified chemoimmunotherapy for PD-L1–negative or high-burden disease is consistent with guideline-based practice and pivotal chemo-IO trials. Positioning ivonescimab + chemotherapy as an “emerging preferred” option is directionally supported by HARMONi-6 (PFS benefit vs tislelizumab + chemo), but its role as a new standard is contingent on regulatory approval, OS/maturity of data, and regional availability.

  1. KEY PRINCIPLES
    Perform molecular profiling before selecting therapy. Base treatment on PD-L1 TPS, disease burden, and patient factors. Use shared decision-making: efficacy goals, toxicity tolerance, patient preference, access/reimbursement. HARMONi-6 full ASCO 2026 data pending.
  2. Advanced / Metastatic Squamous NSCLC
    Stage IV or recurrent not amenable to curative therapy
    • Comprehensive molecular profiling when feasible (particularly important in never/light smokers, mixed histology, or limited tissue samples)
      Comprehensive NGS is not universal in all patients with Squamous Cell NSCLC. However for select patients with mixed histology, light or never smokers, and small biopsies a broad NGS (tissue or plasma) is recommended. Includes: EGFR, ALK, ROS1, BRAF, METex14 skipping, RET, NTRK, KRAS G12C, HER2, etc.
      • Actionable driver detected => Follow approved targeted therapy
        Yes → Use approved targeted therapy (Not part of HARMONi‑6 population)
      • No actionable driver detected => Tumor & Disease Factors / Patient Factors
        Tumor & Disease Factors: PD‑L1 TPS Disease burden (bulky disease, liver mets, extensive nodal disease) Pace of disease (rapidly progressive?) Symptom burden Patient Factors: ECOG performance status Organ function & comorbidities Autoimmune disease history Prior immune‑related toxicity Patient goals & preferences
        • Contraindication to immunotherapy or combination therapy?
          Active autoimmune disease Prior severe ICI toxicity / irAE Uncontrolled comorbidities Organ transplant
          • Non-IO option (platinum-doublet chemotherapy)
            If PD‑1/VEGF inhibitors are contraindicated or not appropriate: Platinum‑doublet chemotherapy (e.g., carboplatin + paclitaxel or nab‑paclitaxel) Maintenance: Observation or continuation of chemotherapy per clinical judgment
        • PD‑L1 TPS < 1% or High Disease Burden / Need for Rapid Response (Any PD‑L1)
          • Maximal upfront systemic therapy recommended
            Is standard PD-1-based chemoimmunotherapy enough? Standard chemoimmunotherapy: platinum-doublet + PD-(L)1 Can stronger immune activation improve outcomes? Dual checkpoint strategy: platinum-doublet with CTLA4 + PD-(L)1 inhibitor Can immune activation plus microenvironment modification improve outcomes? Bispecific/VEGF strategy: platinum-doublet + ivonescimab
            • Emerging bispecific/VEGF strategy: Ivonescimab + platinum-doublet chemotherapy (HARMONi-6)
              Ivonescimab + Platinum‑Doublet Chemotherapy (e.g., carboplatin + paclitaxel or nab‑paclitaxel). Contraindication: ivonescimab should not be used in patients with imaging evidence of tumor invasion of major blood vessels. These patients were excluded from HARMONi-6 due to concerns for respiratory hemorrhage. Alternative: Tislelizumab + Platinum‑Doublet Chemotherapy IO monotherapy (e.g., pembrolizumab) may be considered only in carefully selected patients with low tumor burden, minimal symptoms, and high likelihood of durable response
              • Induction systemic therapy (typically 4–6 cycles platinum-doublet–based therapy)
                Ivonescimab or tislelizumab + platinum‑doublet chemotherapy per selected regimen
                • Maintenance phase (continue assigned immunotherapy-based regimen until progression or unacceptable toxicity)
                  Continue ivonescimab (HARMONi‑6 regimen) or tislelizumab as single‑agent maintenance until disease progression, unacceptable toxicity, up to 2 years (per product label and clinical judgment) or completion of planned duration.
        • PD‑L1 TPS 1–49% or Intermediate Disease Burden
          • Chemoimmunotherapy recommended; consider enhanced upfront strategy in selected patients
            Is standard PD-1-based chemoimmunotherapy enough? Standard chemoimmunotherapy: platinum-doublet + PD-(L)1 Can stronger immune activation improve outcomes? Dual checkpoint strategy: platinum-doublet with CTLA4 + PD-(L)1 inhibitor Can immune activation plus microenvironment modification improve outcomes? Bispecific/VEGF strategy: platinum-doublet + ivonescimab
            • Emerging bispecific/VEGF strategy: Ivonescimab + platinum-doublet chemotherapy (HARMONi-6)
              Ivonescimab + Platinum‑Doublet Chemotherapy (e.g., carboplatin + paclitaxel or nab‑paclitaxel). Contraindication: ivonescimab should not be used in patients with imaging evidence of tumor invasion of major blood vessels. These patients were excluded from HARMONi-6 due to concerns for respiratory hemorrhage. Alternative: Tislelizumab + Platinum‑Doublet Chemotherapy IO monotherapy (e.g., pembrolizumab) may be considered only in carefully selected patients with low tumor burden, minimal symptoms, and high likelihood of durable response
              • Induction systemic therapy (typically 4–6 cycles platinum-doublet–based therapy)
                Ivonescimab or tislelizumab + platinum‑doublet chemotherapy per selected regimen
                • Maintenance phase (continue assigned immunotherapy-based regimen until progression or unacceptable toxicity)
                  Continue ivonescimab (HARMONi‑6 regimen) or tislelizumab as single‑agent maintenance until disease progression, unacceptable toxicity, up to 2 years (per product label and clinical judgment) or completion of planned duration.
        • PD‑L1 TPS ≥ 50% and Lower Disease Burden
          low-volume disease minimally symptomatic disease frail patients patients wishing to avoid chemotherapy toxicity
          • IO monotherapy
            PD-(L)1 monotherapy recommended. In PD-L1 TPS ≥50%, pembrolizumab monotherapy is evidence-based and guideline-endorsed for selected patients, while chemoimmunotherapy remains widely used to maximize response probability, particularly when disease burden/symptoms are present.
            • Continue IO until progression/toxicity
              Consider chemoimmunotherapy or emerging intensified approaches when greater upfront disease control is desired.
        • PD‑L1 TPS ≥ 50% and High Disease Burden
          High Disease burden gets ChemoIO.
          • Chemoimmunotherapy remains standard
            Platinum-doublet + PD-(L)1 => current standard escalation Platinum-doublet + ivonescimab => emerging intensified biologic approach informed by HARMONi-6. Still awaiting data from the ongoing HARMONi-3 study which includes a global population. Randomized squamous NSCLC data support PD-1 + platinum/taxane as a standard first-line option across PD-L1 strata, and guidelines list such chemo-IO regimens as preferred options.
            • Emerging bispecific/VEGF strategy: Ivonescimab + platinum-doublet chemotherapy (HARMONi-6)
              Ivonescimab + Platinum‑Doublet Chemotherapy (e.g., carboplatin + paclitaxel or nab‑paclitaxel). Contraindication: ivonescimab should not be used in patients with imaging evidence of tumor invasion of major blood vessels. These patients were excluded from HARMONi-6 due to concerns for respiratory hemorrhage. Alternative: Tislelizumab + Platinum‑Doublet Chemotherapy IO monotherapy (e.g., pembrolizumab) may be considered only in carefully selected patients with low tumor burden, minimal symptoms, and high likelihood of durable response
              • Induction systemic therapy (typically 4–6 cycles platinum-doublet–based therapy)
                Ivonescimab or tislelizumab + platinum‑doublet chemotherapy per selected regimen
                • Maintenance phase (continue assigned immunotherapy-based regimen until progression or unacceptable toxicity)
                  Continue ivonescimab (HARMONi‑6 regimen) or tislelizumab as single‑agent maintenance until disease progression, unacceptable toxicity, up to 2 years (per product label and clinical judgment) or completion of planned duration.
  3. HOW HARMONi‑6 INFORMS PRACTICE
    Population: untreated advanced squamous NSCLC without actionable drivers HARMONi-6: ivonescimab + chemo improved PFS vs tislelizumab + chemo Pembrolizumab-chemo remains a major global standard. Ivonescimab + chemo may become an emerging new standard Individualize based on disease biology and patient factors
tosprivacyIvonescimab plus chemotherapy versus tislelizumab plus chemotherapy as first-line treatment for advanced squamous non-small-cell lung cancer (HARMONi-6): a randomised, double-blind, phase 3 trial