OnCo
drugsProductPhase 3

Fianlimab

Fianlimab is Regeneron's LAG-3 blocker. Promising early data with cemiplimab did not hold up against pembrolizumab in a first-line phase 3 in 2026.

Phase 1 with cemiplimab reported ORR ~60% in first-line melanoma, prompting phase 3 trials versus pembrolizumab in metastatic disease (missed PFS, 2026) and in the adjuvant setting (ongoing). Also being tested in NSCLC. The result narrows the LAG-3 story to the specific nivolumab-relatlimab pairing so far.

Schematic of the modality · Monoclonal antibody (anti-LAG-3) · not a molecule; see the Immune checkpoint inhibitors page
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Immune checkpoint inhibitors
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1.Blocks LAG-3 on exhausted T cells

Modality
Monoclonal antibody (anti-LAG-3)
Mechanism
Fully human IgG4 blocking LAG-3 binding to MHC class II and FGL1.
Brand / code
REGN3767

Regulatory

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  1. 2026DesignationUS

    First-line metastatic phase 3 missed its primary PFS endpoint (Regeneron release)

Trials

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Recruiting now (live from ClinicalTrials.gov)

Recruiting trials near you · live from ClinicalTrials.gov
Fianlimab
intervention: Fianlimab
Open on ClinicalTrials.gov →

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Landmark trials in OnCo

Latest papers

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Literature trend3 papers in the last 12 monthsHow this is computed
Latest papers · live from Europe PMC
Open in Europe PMC

Query for this drug: (TITLE:"Fianlimab" OR ABSTRACT:"Fianlimab" OR TITLE:"REGN3767" OR ABSTRACT:"REGN3767") AND (cancer OR tumor OR tumour OR oncology OR carcinoma OR lymphoma OR leukemia OR leukaemia OR myeloma OR sarcoma OR melanoma OR glioma). Results are unfiltered search hits about Fianlimab, not a curated reading list.

Connected

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