Positive progression-free survival (PFS) results from the RADIANT-4 and NETTER-1 trials extend the armamentarium for physicians treating patients with neuroendocrine tumours (NETs).
The studies, indicating efficacy for the mTOR inhibitor everolimus and the peptide receptor radionuclide therapy lutetium (Lu)177-dotatate, respectively, were presented at the European Cancer Congress held in Vienna, Austria.
The primary endpoint of PFS in the RADIANT-4 trial, as determined by central radiological review, was 11.0 months in the 205 patients with non-functional NETs of the gastrointestinal tract or lung who were randomly assigned to receive everolimus 10 mg/day compared with 3.9 months in the 97 patients given placebo, with a significant hazard ratio (HR) of 0.48.
The “robust benefit” was confirmed by investigator assessment, with PFS of 14.0 months versus 5.5 months in the everolimus and placebo groups, and a significant HR of 0.39.
The first planned interim overall survival analysis showed a 36% reduction in the risk of death in favour of everolimus and, although this was not statistically significant, the researchers believe that analysis of mature data in 2016 may show a significant result.
“Although we knew from previous studies that everolimus could delay the growth of pancreatic NETs, this is the first time we have been able to conclusively show that it is effective in other NET sites”, said James Yao, from the University of Texas MD Anderson Cancer Center in Houston, USA, and RADIANT-4 co-investigators in a press release.