LONDON, July 10 — The technical reality of cancer immunotherapy is that it harnesses the body’s immune system to fight cancer. Under the hood, that means drugs that release the molecular brakes on T-cells, and the results, as of 2024, have been striking enough to reshape the oncology landscape. The detail that matters is that the U.S. Food and Drug Administration has approved more than 20 immunotherapy drugs since 2011.
The two that have set the pace are pembrolizumab, sold as Keytruda and approved in 2014, and nivolumab, sold as Opdivo and also approved in 2014. Both are checkpoint inhibitors, the class of drug that Dr. James Allison pioneered — work that won him the 2018 Nobel Prize in Physiology or Medicine.
In late-stage clinical trials reported in 2023, combination therapies pairing these checkpoint inhibitors with other agents achieved a 40% higher overall survival rate compared with standard chemotherapy for certain cancers. The specific cancers that showed this improvement were advanced melanoma and non-small cell lung cancer. That is not a marginal gain; it is the kind of signal that changes clinical practice.
The global immunotherapy market was valued at approximately $126 billion in 2022 and is projected to reach $196 billion by 2027, according to a 2023 report by Grand View Research. Those numbers reflect both the scientific momentum and the commercial reality: these are expensive biologics, and the patient population that can benefit is growing.
The American Cancer Society estimates that immunotherapy now benefits about 15% of cancer patients in the United States. That figure, as ever, cuts both ways. It represents real progress for a significant minority, but it also means the majority of patients still do not respond to these drugs.
The field is not done. For patients with previously untreatable cancers, these advances have opened options where none existed. The side-effect profile remains a concern: immune-related adverse events, where the unleashed immune system attacks healthy tissue, can be severe and require careful management.
It is not a free lunch. Checkpoint inhibitors work by blocking proteins on T-cells that act as off-switches.
Tumours exploit these switches to evade attack. By disabling the brake, the drugs allow the immune system to recognise and kill cancer cells. The elegance of the mechanism is also its vulnerability — the same precision that makes the therapy effective can also trigger autoimmune-like inflammation in the colon, lungs, skin, or endocrine system.
Pembrolizumab and nivolumab were both approved by the FDA in 2014, initially for advanced melanoma. Their approval for non-small cell lung cancer followed, and the list of indications has expanded steadily since.
The 2023 trial data showing a 40% survival advantage for combination regimens in these two cancers is the kind of evidence that drives guideline changes. The $126 billion valuation of the global immunotherapy market in 2022, with a projected climb to $196 billion by 2027, reflects a pipeline that is dense with new candidates and combination strategies. The FDA’s approval of more than 20 immunotherapy drugs since 2011 is a measure of how fast the field has moved from laboratory discovery to standard-of-care.
Key organisations involved include the FDA, which regulates the drugs, and the American Cancer Society, which tracks patient benefit. Dr. James Allison’s Nobel Prize in 2018 remains the single most prominent recognition of the science behind checkpoint inhibition. His discovery provided the mechanistic foundation for the entire class.
The 15% of U.S. cancer patients currently benefiting from immunotherapy is a figure that researchers are working to increase. Combination therapies — pairing checkpoint inhibitors with chemotherapy, radiation, or other immunomodulators — are the most active area of clinical investigation.
The 2023 trial data for advanced melanoma and non-small cell lung cancer suggests that the combination approach can extend survival beyond what either drug class achieves alone. The side-effect profile remains the limiting factor. Immune-related adverse events can be unpredictable and, in rare cases, fatal.
Managing them requires specialist teams and protocols that are still being refined. As ever, the technical challenge is to widen the therapeutic window — to boost the immune attack on tumours while keeping collateral damage to normal tissue within acceptable bounds.
The detail that matters for patients is that immunotherapy is no longer experimental. It is a registered, reimbursed, and increasingly standard option for several cancers. The wry observation is that the body’s own defences, once unleashed, do not always follow orders.
But for the 15% who respond, the difference can be transformative. Consult your doctor for medical advice.
