Background: Cancer cachexia is characterized by the loss of body weight (BW) and anorexia. Anamorelin (ANAM) is a selective ghrelin receptor agonist with appetite-enhancing anabolic action. The ONO-7643-05 trial demonstrated that ANAM increased lean body mass and improved anorexia in a Japanese population. However, the clinical outcomes of patients on ANAM have not yet been reported.
Patients and methods: We investigated the clinical outcomes of patients with unresectable, advanced, or recurrent gastrointestinal cancer (colorectal, gastric, or pancreatic cancer) who were treated with ANAM between April 2017 and August 2022. Cachexia was defined as the presence of anorexia and a loss of ≥ 5% of BW within 6 months. To evaluate the response to ANAM, the patients who had discontinued ANAM within 3 weeks were excluded. Response to ANAM was defined as maintenance of or increase in BW and improved appetite from baseline at every 3-week evaluation. We also collected data on the reasons for the discontinuation of ANAM and the correlation between clinical factors and ANAM response. Safety analysis of ANAM was performed for all patients who received ANAM.
Results: Seventy-four patients were included in this study (49 males and 25 females), with a median age of 67.1 years (range, 36-83). The primary tumors were colorectal cancer in 27 (36.5%), gastric cancer in 20 (27.0%), and pancreatic cancer in 27 (36.5%). The Eastern Cooperative Oncology Group performance status was 0 in 10 (13.5%), 1 in 44 (59.5%), and ≥ 2 in 20 (27.0%). The number of previous chemotherapy regimens was 0 in 20 (27.0%), 1 in 22 (29.7%), and ≥ 2 in 32 (43.2%). ANAM was discontinued within 3 weeks in 28 patients for the following reasons: low-grade (grade 1 or 2) adverse events in 15 patients, ileus in three, grade 3 fatigue in one, progressive disease in one, censored follow-up in six, and unknown reasons in three. The proportion of ANAM responders was 63.6% (95% confidence interval, 47.8-77.6%). Among baseline characteristics, age ≥ 75 attenuated the ANAM response (p = 0.03). ANAM responders showed better disease control with chemotherapy than non-responders (75.0% vs. 37.5%, p = 0.02).
Conclusions: ANAM may improve the outcomes of patients with gastrointestinal cancer cachexia in clinical practice.