Novartis has reported findings of a final analysis of data from the Phase III Netter trial, showing that its radioligand therapy Lutathera (INN: lutetium (177Lu) oxodotreotide / USAN: lutetium Lu 177 dotatate) extended overall survival in patients with midgut neuroendocrine tumours.

The drugmaker previously published a primary analysis of data from the trial, which compared Lutathera plus 30mg octreotide LAR to 60mg of octreotide LAR, showing a statistically significant improvement in progression free survival (PFS).

In the final analysis of overall survival, a secondary objective of the trial, treatment with Lutathera resulted in a clinically relevant prolongation in median overall survival of 11.7 months.

While this analysis did not reach statistical significance, the analyses of overall survival may have been impacted by multiple factors, including the crossover of patients from the control arm receiving subsequent radioligand therapy (36% of patients) as well as heterogenous subsequent anti-cancer treatments in both study arms, the firm noted.

"Lutathera plus long-acting octreotide was associated with a nearly 12-month difference in median overall survival compared to high-dose long-acting octreotide in these difficult to treat patients with inoperable midgut NETs progressing under standard dose octreotide LAR treatment. While not statistically significant, I consider this difference to be clinically relevant for these patients,” said Jonathan Strosberg, principal investigator and associate professor, Section Head, Neuroendocrine Tumor Program at Moffitt Cancer Center.

“It is also important to emphasise that PFS was the primary endpoint of this study. Moreover, 36% of patients in the control arm crossed over to receive subsequent radioligand treatment, which may have impacted the comparison of survival between both study arms.”

The results will be presented later during the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting on June 4.