Inlyta-Synthetic Hormone Combo Fails to Significantly Improve Survival Outcome in Pancreatic Neuroendocrine Tumors

The combination of Inlyta (axitinib) and the synthetic hormone octreotide acetate failed to significantly improve progression-free survival, compared to placebo with the synthetic hormone. However, the results indicated the Inlyta-based combination did improve disease response in patients versus the placebo-based combination.

Findings from a phase 2/3 study demonstrated that Inlyta (axitinib) combined with the synthetic hormone octreotide acetate failed to significantly improve progression-free survival (length of time during and after cancer treatment that a patient is alive but the disease does not get worse) in patients with advanced extra-pancreatic neuroendocrine tumors (NETs), compared to placebo plus octreotide acetate.

The data, which were presented during the virtual 2021 American Society of Clinical Oncology Gastrointestinal Cancers Symposium, did, however, demonstrate that that the Inlyta-based combination improved response rates.

The study authors randomized 256 patients (median age, 61 years; range, 21 to 85 years) to receive either the Inlyta and octreotide acetate combination (126 patients) or placebo plus the synthetic hormone (130 patients). Measuring progression-free survival was the main goal of the study. Secondary goals included assessing overall response rates, duration of response, overall survival and safety.

A potent and selective VEGFR inhibitor, Inlyta has been effective in treating other vascular-dependent solid tumors. However, according to the study authors, therapeutic options for patients with pancreatic NETs are limited.

Patients were eligible for study entry if they had received two previous lines of systemic therapy, but they were excluded if they had received prior antiangiogenic agents. Patients were separated into groups based on time from diagnosis to inclusion into the study (greater than 12 months versus 12 months or less) and location of primary tumor (gastrointestinal tract versus non-gastrointestinal tract).

Although investigator-assessed median progression-free survival favored the Inlyta arm (17.2 months) compared to the placebo arm (12.3 months), the authors noted that the difference was not statistically significant.

However, patients in the Inlyta arm achieved a greater overall response to therapy (17.5%) compared to those in the placebo arm (3.8%). Sixty-nine percent of patients demonstrated tumor shrinkage in the treatment arm compared with 44% of patients in the placebo arm.

Patients in both the Inlyta arm and placebo arm discontinued treatment because of disease progression (45.2% vs. 63.8%), adverse events (23.8% vs. 4.6%), consent withdrawal (4% vs. 3.1%) and death (3.2% vs. 2.3%), respectively.

The authors noted that the occurrence of all-grade adverse events in this study were similar to previous safety profiles of Inlyta. Diarrhea (63.2%), weakness (52%), hypertension (50.4%) and inflammation of the mouth or gut (28.8%). Patients in the Inlyta arm (52%) were more likely to experience more serious or severe adverse events compared to those in the placebo arm (14%). One patient in the Inlyta arm died due to heart failure and two deaths in the placebo arm occurred because of myocardial infarction (heart attack) and hepatorenal syndrome (a life-threatening condition that affects kidney function in patients with advanced liver disease).

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.

A version of this article originally appeared on OncLive® as “Axitinib/Octreotide Combo Fails to Improve PFS in Pancreatic NETs.”