According to researchers from Dana-Farber Cancer Institute, USA, a drug combination could potentially become the first-line treatment for patients with advanced kidney cancer.
Patients who received the drug combination of the immunotherapy drug avelumab and axitinib, a targeted agent, showed to have a significant advantage in progression-free survival compared with those who received sunitinib (Sutent), a targeted drug that has been a standard treatment for advanced clear cell renal cell carcinoma – the most common form of advanced kidney cancer.
Let’s talk drug combinations
Toni K. Choueiri, Professor of Medicine at Harvard Medical School, USA, explains: “Patients receiving the drug combination also had a higher response rate – meaning their tumours shrank – than the sunitinib-only group.”
“This is certainly better than sunitinib – hopefully this will lead to Food and Drug Administration approval soon.”
While progression-free survival was improved with the drug combination treatment, supplementary follow-up will be required to show whether the two-drug therapy extends overall survival compared to the standard regimen.
The trial is the first pivotal study to combine avelumab with a drug that targets the vascular endothelial growth factor receptor (VEGFR).
VEGFR blockers like sunitinib and axitinib are designed to starve tumours by disrupting their blood supply. Immunotherapy drugs such as avelumab – which blocks an immune checkpoint called PD-L1 – work by activating ‘exhausted’ immune T cells so they can more effectively attack cancer cells.
Details of the study
The clinical trial involved 886 patients with previously untreated, advanced renal cell carcinoma who were randomised to receive the drug combination or sunitinib alone.
The results presented that the median progression-free survival (PFS) – the period of time before the cancer began to worsen – was 13.8 months in the combination group and 7.2 months in patients receiving only sunitinib.
These results specifically applied to patients whose cancer cells tested positive for the PD-L1 checkpoint that is blocked by avelumab. The PFS for the overall population (PD-L1 positive or negative) was similar – 13.8 months versus 8.4 months.
The proportion of patients whose tumours shrank was 55.2% with avelumab plus axitinib and 25.5% with sunitinib in the patients who were positive for PD-L1.
Are patients benefitting from the drug combination treatment?
Nearly all patients in both treatment groups experienced some side effects. In the combination treatment group, 38.2% of patients experienced immune-related adverse events, the most frequent being thyroid disorders, observed in 107 patients.
Choueiri said that for patients with advanced disease, “this is an important option. What we’re doing in advanced kidney cancers is pushing the envelope – these treatments may not be curative, but patients are living longer, and the disease is becoming more chronic.”
Nevertheless, Choueiri adds: “Interestingly, the analysis showed that all subgroups – good, intermediate, and poor-risk patient – benefited from the combination treatment.”