Doctors have hailed the results of a major international clinical trial after a triple-action cancer injection demonstrated an unprecedented ability to shrink, and in some cases completely eliminate, tumours in patients whose disease had stopped responding to existing treatments.
The study involved patients whose cancer had either spread or returned and who had exhausted standard treatment options, including chemotherapy and immunotherapy. Researchers reported that the injection, known as amivantamab, reduced tumour size in more than one-third of participants, with some patients experiencing dramatic improvements within weeks.
Strong responses in difficult-to-treat patients
According to researchers, the treatment produced especially encouraging outcomes among patients with advanced head and neck cancer, a disease that is often challenging to treat once conventional therapies fail.
Among 102 patients enrolled in the trial, tumours either shrank significantly or disappeared entirely in 43 individuals. Of these, 28 experienced substantial tumour reduction, while 15 saw their tumours eradicated completely.
Professor Kevin Harrington, a specialist in biological cancer therapies at the Institute of Cancer Research in London and a consultant oncologist at the Royal Marsden NHS Foundation Trust, described the findings as unprecedented.
He said the responses were particularly striking because the patients had already developed resistance to both chemotherapy and immunotherapy, leaving them with very limited treatment options.
He added that the treatment could potentially benefit many thousands of patients each year.
The findings are scheduled to be presented at the annual meeting of the American Society of Clinical Oncology in Chicago, the world’s largest cancer conference.
Triple-action approach targets cancer on multiple fronts
Researchers explained that amivantamab attacks cancer through three distinct mechanisms. The drug blocks EGFR, a protein that helps tumours grow, and MET, a pathway often used by cancer cells to evade treatment. It also helps activate the body’s immune system to attack cancer cells.
The treatment has also shown similar results in patients with lung cancer. Developed by Johnson & Johnson, amivantamab is currently being assessed in around 60 clinical trials involving several cancer types, including lung, colorectal, brain and gastric cancers.
Unlike many cancer therapies that require intravenous infusions, amivantamab is administered through a small injection under the skin. This makes treatment faster and more convenient for patients while simplifying delivery in outpatient settings.
The injection is given once every three weeks, and most side effects reported during the trial were mild to moderate. Fewer than one in ten patients discontinued treatment because of side effects.
Patient reports significant improvement in quality of life
One of the earliest participants to benefit from the treatment was 56-year-old Carl Walsh, who was diagnosed with tongue cancer in May 2024 before joining the OrigAMI-4 trial at the Royal Marsden in July 2025.
Walsh said chemotherapy and immunotherapy had initially failed to control his disease, leading doctors to recommend enrolment in the clinical trial.
He is currently undergoing his 17th treatment cycle and reported significant improvements in his condition. Before joining the study, he struggled with speech difficulties and eating because of pain and swelling. Following treatment, both symptoms improved substantially.
Walsh also said the severe side effects he experienced during chemotherapy were no longer affecting his daily life.
At the worst stage of his illness, his diet consisted mainly of soft foods and nutritional supplements, and he lost a considerable amount of weight. However, after only two treatment cycles, his eating habits began returning to normal. Within six months, he had resumed a full diet.
He also reported that his speech had returned to normal, allowing him to communicate comfortably at work.
Researchers noted that the trial focused on patients with head and neck cancers that excluded HPV-positive oropharyngeal squamous cell carcinoma. They highlighted the significance of this distinction, as cancers not linked to HPV are generally more difficult to treat.
Patients receiving amivantamab survived for a median of 12.5 months after beginning treatment, despite facing a form of cancer associated with poor outcomes once standard therapies cease to be effective.
Professor Kristian Helin, chief executive of the Institute of Cancer Research, said the study demonstrated how rigorous cancer research could lead to meaningful advances for patients with very limited treatment options.
He said the level of tumour response achieved, together with encouraging survival outcomes, represented a significant step forward for a particularly difficult-to-treat patient group.
