Drug combination may treat advanced kidney cancer

Washington: An investigator from Dana-Farber Cancer Institute now says that a combination of two drugs – one of them an immunotherapy agent – could become a new standard, first-line treatment for patients with metastatic kidney cancer. The investigator made the claims after the release of results from a phase 3 clinical trial.

The study found that patients who received the immunotherapy drug avelumab plus axitinib, a targeted agent, had 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 kidney cancer.

Speaking about it, senior and co-corresponding author of the report Toni K. Choueiri said, “Patients receiving the drug combination also had a higher response rate – meaning their tumours shrank – than the sunitinib-only group.”

While progression-free survival was improved with the combination treatment, additional follow-up is needed 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.

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 from this study showed that the median progression-free survival (PFS) – the length 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 per cent with avelumab plus axitinib and 25.5 per cent with sunitinib in the patients who were positive for PD-L1.

According to Choueiri, the analysis showed that all subgroups benefited from the combination treatment.
However, nearly all patients in both treatment groups experienced some side effects.

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.”