OnCo

The first immune brake ever targeted for cancer; releasing it won a Nobel Prize and cures a fraction of melanomas. This dossier gathers the 3 products (3 approved), 15 trials, 3 pathways and 0 resistance routes in the corpus that involve it, with external identifiers so it can be joined to UniProt, ChEMBL, Open Targets and the rest of biology.

Biology

Competes with CD28 for B7 ligands during T-cell priming; also depletes regulatory T cells via Fc effector function.

Where it is found
  • Activated and regulatory T cells
Class: checkpoint · Gene: CTLA4 · Facts checked 2026-09-04 · Target page
Technologies aimed at it

Elsewhere: identifiers and databases

Built from HGNC, Ensembl, UniProt and ChEMBL ids

How common it is, by cancer

Full matrix →
CancerPrevalenceSource
Melanoma
n/a
Wikipedia

Approximate, population-level figures; the measure column says what was counted. Ranges show the midpoint as a bar.

Products by modality and phase

Browse products →
ModalityApproved
Antibody
2
Bispecific antibody
1
TrialPhaseStatus
EMERALD-3
NCT05301842
3Positive
CheckMate 8HW
NCT04008030
3Positive
CheckMate 9DW
NCT04039607
3Positive
COMPASSION-16 / AK104-303
NCT04982237
3Positive
NADINA
NCT04949113
3Positive
COSMIC-313
NCT03937219
3Mixed
HIMALAYA
NCT03298451
3Positive
CheckMate 648
NCT03143153
3Positive
DREAMseq (ECOG-ACRIN EA6134)
NCT02224781
3Positive
CheckMate 743
NCT02899299
3Positive
CASPIAN
NCT03043872
3Positive
CheckMate 214
NCT02231749
3Positive
CheckMate 067
NCT01844505
3Positive
KEYNOTE-006
NCT01866319
3Positive
NICHE-2
NCT03026140
2Positive

Resistance routes that involve this target

Unaddressed routes →

The resistance atlas has no route that names this target.

Pathways where it is a node

Pathway-to-drug matrix →
  • PD-1 / PD-L1 immune checkpoint & T-cell activation
    Node: CTLA-4 (stop) · 4 druggable nodes

    How T cells decide to attack. A T cell needs to see the target (TCR-MHC) and get a 'go' signal (CD28). PD-1 and CTLA-4 are 'stop' signals; tumours exploit them. Checkpoint inhibitors remove the stop.

    Which nodes have drugs →
  • The cancer-immunity cycle
    Node: 3 Priming (CD28 / CTLA-4) · 3 druggable nodes

    Seven steps the immune system must complete to kill a tumour: release of antigens, pick-up by dendritic cells, priming of T cells in lymph nodes, travel, entry into the tumour, recognition, and killing. Every immunotherapy pushes on one step; every escape blocks one.

    Which nodes have drugs →
  • Tumour microenvironment (TME)
    Node: Tregs (CTLA-4) · 5 druggable nodes

    A tumour is not just cancer cells. It is a neighbourhood of fibroblasts, immune cells, blood vessels, nerves, and scaffolding that the cancer recruits and corrupts, and that decides whether drugs and immune cells can get in.

    Which nodes have drugs →

Companion diagnostics and assays

Assay registry →
AssayPlatformCut-off
MSI by PCR (Promega MSI Analysis System and equivalents)
Promega and others · LDT
PCRInstability at two or more of five markers (MSI-high); NGS panels report MSI from hundreds of loci

Preclinical models

All models →

No model entry for this target yet; check the cancer entries on the models page.

No open questions recorded for this target yet. Suggest one.

Ideas and companies

Companies with products against it · 3

Key papers and the live literature

Preprints →
Latest papers · live from Europe PMC
Open in Europe PMC

Query for this target: (TITLE:"CTLA-4" OR ABSTRACT:"CTLA-4" OR TITLE:"CTLA4" OR ABSTRACT:"CTLA4") 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 CTLA-4, not a curated reading list.

Export

The dossier as machine-readable JSON: identifiers from HGNC, Ensembl, UniProt and ChEMBL, products with status, trials, pathways, hotspots, open questions and assays. The full entity record is in the open API at /api/v1/entities/ctla4.json. Licence CC BY 4.0.