Loading
CD47 is the 'don't eat me' signal: it binds SIRP-alpha on macrophages to stop them engulfing the cell, and over 90% of AML blasts and large B-cell lymphoma cells display it. Blocking it should let macrophages eat tumour cells, but red cells carry CD47 too, so anaemia is built in, and the lead antibody magrolimab was dropped after failed trials.
CD47 is the 'don't eat me' signal: it binds SIRPα on macrophages to inhibit phagocytosis, and tumour cells display it broadly, with more than 90 percent of AML blasts and DLBCL cells carrying it. Blocking CD47 should let macrophages engulf tumour cells, particularly when combined with an opsonising antibody such as rituximab or with azacitidine. Because CD47 is also ubiquitous on red cells, anaemia is the built-in on-target toxicity. Magrolimab, the lead antibody, was discontinued after failed trials in MDS and AML (ENHANCE), with excess deaths. The macrophage checkpoint concept persists through SIRPα-targeted agents and bispecifics designed to spare red cells and lower haematological toxicity. For a newcomer: it looked like a promising immune brake on macrophages, but the first drug against it failed.
In plain words · CD47 is the 'don't eat me' signal: it binds SIRP-alpha on macrophages to stop them engulfing the cell, and over 90% of AML blasts and large B-cell lymphoma cells display it. Blocking it should let macrophages eat tumour cells, but red cells carry CD47 too, so anaemia is built in, and the lead antibody magrolimab was dropped after failed trials.
CD47 is the 'don't eat me' signal: it binds SIRP-alpha on macrophages to stop them engulfing the cell, and over 90% of AML blasts and large B-cell lymphoma cells display it. Blocking it should let macrophages eat tumour cells, but red cells carry CD47 too, so anaemia is built in, and the lead antibody magrolimab was dropped after failed trials.
Binds SIRPα on macrophages to inhibit phagocytosis; ubiquitous on red cells, causing anaemia.
4 products aim at CD47: antibodies and bispecific antibodies. Checkpoint drugs are antibodies that cover one side of an immune ‘stand down’ handshake so T cells stay active.
Immune or microenvironment target: the record's class is immune checkpoint. HPA CD47: RNA low tissue specificity; high antibody staining in 5 normal tissues; highest cancer staining ovarian cancer (6 of 11 high). Distribution: 2 cancer families in the corpus carry a prevalence row, label threshold or catalogue link for it (Leukaemia, Lymphoma); Open Targets associates it with 0 specific cancer types at or above 0.5. (Rule 1 of scripts/fetch-target-specificity.ts.)
Sources: Human Protein Atlas CD47 tissue; UniProt Q08722; Open Targets ENSG00000196776 associations
First described 1992. Earliest sequence paper UniProt cites for the protein: Campbell I.G. et al, Cancer Res, 1992, "An ovarian tumor marker with homology to vaccinia virus contains an IgV-like region and multiple transmembrane domains". Source.
Binds SIRPα on macrophages to inhibit phagocytosis; ubiquitous on red cells, causing anaemia.
RNA: low tissue specificity, detected in all normal tissues.
Medium: Breast, Bronchus, Cervix, Colon, Epididymis, Placenta, Rectum, Salivary gland.
Medium only: breast cancer, colorectal cancer, head and neck cancer, liver cancer.
HPA CD47 tissue · HPA CD47 pathology · HPA protein class: CD markers
Human Protein Atlas version 25.1, antibody staining at reliability approved, enhanced or supported; used under CC BY-SA 3.0. Staining counts are patients per level in the atlas cohort, not population prevalence.
| Cancer | Prevalence | Measure | Note | Source |
|---|---|---|---|---|
| Acute myeloid leukaemia | >90% | Surface expression on blasts | Magrolimab discontinued | Wikipedia |
| Diffuse large B-cell lymphoma | >90% | Surface expression | Wikipedia |
Approximate, population-level figures; the measure column says what was counted. Ranges show the midpoint as a bar.
AK117 is an experimental investigational agent whose form is not stated in the registry from Akeso in phase 3 trials for head and neck squamous cell carcinoma, colorectal cancer and non-small-cell lung cancer, with its target not yet stated publicly.
The first 'don't eat me' signal blocker. Gilead paid $4.9B for it; it was stopped in 2024 after trials showed more deaths, not fewer.
Peluntamig is an experimental bispecific antibody from Phanes Therapeutics in phase 2 trials for non-small-cell lung cancer and neuroendocrine tumours, aimed at CD47 and DLL3.
Spevatamig is an experimental bispecific antibody from Phanes Therapeutics in phase 2 trials for gastric & gastro-oesophageal junction cancer, pancreatic ductal adenocarcinoma and biliary tract cancer, aimed at Claudin 18.2 and CD47.
Query for this target: (TITLE:"CD47" OR ABSTRACT:"CD47") 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 CD47, not a curated reading list.
Shares Checkpoint (two meanings), Cold tumours and the immunosuppressive microenvironment and the tags checkpoint, failed-so-far.
Shares Checkpoint (two meanings), Cold tumours and the immunosuppressive microenvironment and the tag checkpoint.
Shares Tumour microenvironment (TME), Checkpoint (two meanings), Cold tumours and the immunosuppressive microenvironment and the tag checkpoint.
Shares Tumour microenvironment (TME), Checkpoint (two meanings), Cold tumours and the immunosuppressive microenvironment and the tag checkpoint.
Shares Tumour-associated macrophages (TAMs), Myeloid suppression: TAMs, MDSCs & don't-eat-me signals, Tumour microenvironment (TME), Checkpoint (two meanings) and the tag checkpoint.
Shares Can MYC be drugged directly, and will patients tolerate it?, Engineered bacteria that live in tumours and manufacture drugs there, Make every cold tumour hot: a coordinated programme to reprogramme immune-excluded tumours.
Shares CD24, Macrophage, Checkpoint (two meanings).
Shares Inhaled immune therapy to make the lung hostile to arriving tumour cells, Engineered bacteria that live in tumours and manufacture drugs there, Make every cold tumour hot: a coordinated programme to reprogramme immune-excluded tumours, Cold tumours and the immunosuppressive microenvironment.