# Immuno-oncology (IO) and checkpoint blockade

Source: https://onco.cc/terms/immuno-oncology/  
OnCo record `immuno-oncology` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Treatments that take the brakes off the patient's own immune system so it attacks the cancer, chiefly antibodies against PD-1, PD-L1 and CTLA-4. 'IO' is industry shorthand; 'chemo-IO' means chemotherapy plus a checkpoint inhibitor, the commonest first-line combination.

## Summary

Since ipilimumab (2011) and pembrolizumab/nivolumab (2014), checkpoint inhibitors have become standard in melanoma, lung, kidney, bladder, head and neck, liver, gastric, oesophageal, cervical, endometrial, triple-negative breast and MSI-high cancers, and in curative settings before and after surgery. Benefit tracks PD-L1 expression, tumour mutational burden and MSI status but imperfectly; 'cold' tumours (pancreatic, prostate, MSS colorectal, most glioblastoma) remain resistant, and roughly 40% of responders eventually progress. Immune-related adverse events affect any organ. Next steps include LAG-3, TIGIT (mixed), PD-1×VEGF bispecifics (ivonescimab), and combining IO with ADCs.

## Fields

- Kind: Term
- Last checked: 2026-09-09
- Also known as: I-O; immuno-oncology; checkpoint blockade; immune checkpoint blockade; ICB; ICI; ICIs; PD-1 blockade; PD-(L)1; PD-(L)1 blockade; PD-1/PD-L1; anti-PD-1; anti-PD-L1; anti-CTLA-4; anti-PD(L)1; chemo-IO; chemo-immunotherapy; chemoimmunotherapy; IO-based; IO-naive; post-IO; IO-refractory; immunotherapy-refractory; immunotherapy-resistant; dual checkpoint blockade; dual immune checkpoint blockade; IO combination; IO + chemo

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Immune_checkpoint_inhibitor
- Wikipedia: https://en.wikipedia.org/wiki/Immune_checkpoint_inhibitor

## Connected records

- terms: [Checkpoint (two meanings)](https://onco.cc/terms/checkpoint/), [Hot vs cold tumours](https://onco.cc/terms/cold-vs-hot/), [Immune-related adverse events (irAEs)](https://onco.cc/terms/irae/), [Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR)](https://onco.cc/terms/msi/), [Microsatellite-stable (MSS) / mismatch-repair proficient (pMMR)](https://onco.cc/terms/mss-pmmr/), [PD-L1 expression testing (22C3, SP142, SP263)](https://onco.cc/terms/pd-l1-testing/), [Tumour mutational burden (TMB)](https://onco.cc/terms/tmb/)
- fronts: [Immunotherapy](https://onco.cc/fronts/immunotherapy/)
- technologies: [Bispecific antibodies](https://onco.cc/technologies/bispecific-antibody/), [Immune checkpoint inhibitors](https://onco.cc/technologies/checkpoint-inhibitor/)
- drugs: [Atezolizumab](https://onco.cc/drugs/atezolizumab/), [Durvalumab](https://onco.cc/drugs/durvalumab/), [Ipilimumab](https://onco.cc/drugs/ipilimumab/), [Nivolumab](https://onco.cc/drugs/nivolumab/), [Pembrolizumab](https://onco.cc/drugs/pembrolizumab/)
- cancers: [PD-L1-high non-small-cell lung cancer without a driver mutation](https://onco.cc/cancers/pdl1-high-nsclc/)

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JSON: https://onco.cc/api/v1/entities/immuno-oncology.json