Impact of the Extent of Weight Loss before Administration on the Efficacy of Anamorelin in Advanced Pancreatic Cancer Patients with Cachexia

Objective Anamorelin, a novel selective ghrelin receptor agonist, was approved in Japan for the treatment of cachexia in pancreatic cancer (PC), albeit with limited evidence. This study evaluated the efficacy and safety of anamorelin in PC and examined the impact of the extent of weight loss on the efficacy of anamorelin. Methods We retrospectively investigated consecutive PC patients with cachexia who received anamorelin at our institution between June 2021 and January 2022. Patients were divided into two groups: moderate-weight-loss group (5-10%) and severe-weight-loss group (>10%). The primary outcome was changes in body weight. The secondary outcomes were changes in appetite and laboratory measures as well as treatment-related severe adverse events. Results A total of 24 patients were included (moderate/severe weight loss: 8/16). The moderate-weight-loss group showed significantly more weight gain than the severe-weight-loss group. Improvements in appetite were consistently observed in each weight-loss group. Changes in laboratory markers were not significantly different between groups. Hyperglycemia (four patients) was the most common cause of severe adverse events, followed by abdominal distension, nausea, elevated liver function tests, and bulimia. Conclusion The efficacy of anamorelin was associated with the extent of weight loss. Although anamorelin improved appetite in each weight-loss group, it increased body weight only in the moderate-weight-loss group. Anamorelin was well-tolerated among advanced PC patients, although caution must be practiced when it is used in patients with concomitant diabetes mellitus.