BACKGROUND: Octreotide has been used for decades in the United States (US) and Europe to treat patients with advanced neuroendocrine tumors (NETs). Lanreotide was approved in 2014 to improve progressionfree survival (PFS) in patients with unresectable, well- or moderately-differentiated, locally advanced or metastatic gastroenteropancreatic NETs. Therefore, clinicians and patients may consider sequencing therapy from octreotide to lanreotide. However, current real-world outcomes data on patients who have made this transition is limited.
METHODS: We conducted a multicenter, noninterventional, retrospective medical record review of patients with locally advanced or metastatic gastroenteropancreatic NETs (NCT03112694). Included patients had been treated with long-acting octreotide monotherapy for ≥90 days before transitioning to lanreotide monotherapy and continued on lanreotide for ≥90 days. Abstractors entered patient demographic and clinical data into a customized, web-based case report form. We assessed clinically defined PFS and other tumorrelated outcomes while patients were treated with lanreotide. Outcomes were analyzed according to level of response at the time of transition from octreotide to lanreotide: progressive disease, nonprogressive disease, or unknown. Statistical analyses were descriptive. Clinically defined PFS and duration of treatment with lanreotide were estimated using the Kaplan-Meier method.
RESULTS: Data were abstracted for 91 patients with gastroenteropancreatic NETs who received long-acting octreotide followed by lanreotide at six US based sites. At initial diagnosis, 71.4% of patients had stage IV disease. Small intestine (63.7%) and pancreas (14.3%) were the most common primary tumor sites. Mean [standard deviation (SD)] duration of follow-up from diagnosis was 70.6 (41.3) months. Patients received long-acting octreotide for a mean (SD) of 38.4 (32.8) months. When patients transitioned to lanreotide, 57.1% had nonprogressive disease on octreotide, 30.8% had progressive disease, and the remainder had unknown disease status. The most common reasons for switching from octreotide to lanreotide were progressive disease (22.0%), formulary change (15.4%), and patient preference (9.9%). Patients received lanreotide for a median (95% CI) duration of 24.7 (16.7–59.9) months. At the end of follow-up, 74% of patients remained on lanreotide monotherapy. Progression occurred in 24.2% of patients during lanreotide treatment. Overall median (95% CI) clinician-defined PFS following the transition to lanreotide was estimated to be 23.7 months [20.2 months–NE (not estimable)]. Patients with nonprogressive disease when they transitioned to lanreotide experienced a median clinician-defined PFS of 24.7 (17.0–NE) months. Among patients reported to have progressive disease when they transitioned to lanreotide, median (95% CI) clinician-defined PFS was estimated to be 15.2 (11.4–NE) months. There were no material differences in adverse events recorded during the long-acting octreotide and lanreotide treatment periods.
CONCLUSIONS: Our study suggests that lanreotide monotherapy is well tolerated and may contribute to stabilization of disease in a subset of patients with locally advanced or metastatic gastroenteropancreatic NETs previously treated with long-acting octreotide.
