Nivolumab, an immunotherapy drug, has been described as a potential “game-changer” in promising results presented at the European Cancer Congress.

In a study of head and neck cancer, more patients taking the drug survived for longer compared with those who were treated with chemotherapy.

In another study, combining nivolumab with another drug shrank tumors in advanced kidney cancer patients.

Immunotherapy works by harnessing the immune system to destroy cancer cells.

Advanced head and neck cancer has very poor survival rates.

In a trial of more than 350 patients, published in the New England Journal of Medicine, 36% treated with nivolumab (Opdivo) were alive after one year compared with 17% who received chemotherapy.

Patients also experienced fewer side effects from immunotherapy.

The benefits were more pronounced in patients whose tumors had tested positive for HPV (human papillomavirus). These patients survived an average of 9.1 months with nivolumab and 4.4 months with chemotherapy.

Normally, this group of patients are expected to live less than six months.

Early data from a study of 94 patients with advanced kidney cancer showed that the double hit of nivolumab and ipilimumab resulted in a significant reduction in the size of tumors in 40% of patients.

Of these patients, one in 10 had no sign of cancer remaining.

This compares with 5% of patients showing tumor reduction after standard therapy.

Nivolumab and ipilimumab both work by interrupting the chemical signals that cancers use to convince the immune system they are healthy tissue.