Background: Cancer anorexia-cachexia is a debilitating condition frequently observed in NSCLC patients, characterized by decreased body weight, reduced food intake, and impaired quality of life. Anamorelin, a novel selective ghrelin receptor agonist, has anabolic and appetite-enhancing activities. Patients and methods: ROMANA 3 was a safety extension study of two phase 3, double-blind studies that assessed safety and efficacy of anamorelin in advanced NSCLC patients with cachexia. Patients with preserved Eastern Cooperative Oncology Group ≤ 2 after completing 12 weeks (w) on the ROMANA 1 or ROMANA 2 trials (0-12 weeks) could enroll in ROMANA 3 and continue to receive anamorelin 100 mg or placebo once daily for an additional 12w (12-24 weeks). The primary endpoint of ROMANA 3 was anamorelin safety/tolerability (12-24 weeks). Secondary endpoints included changes in body weight, handgrip strength (HGS), and symptom burden (0-24 weeks). Results: Of the 703 patients who completed ROMANA 1 and ROMANA 2, 513 patients entered ROMANA 3 (anamorelin, N = 345, mean age 62.0 years; placebo, N = 168; mean age 62.2 years). During ROMANA 3, anamorelin and placebo groups had similar incidences of treatment-emergent adverse events (TEAEs; 52.2% versus 55.7%), grade ≥ 3 TEAEs (22.4% versus 21.6%), and serious TEAEs (12.8% versus 12.6%). There were 36 (10.5%) and 23 (13.8%) deaths in the anamorelin and placebo groups, respectively; none were drug-related. Improvements in body weight and anorexia-cachexia symptoms observed in the original trials were consistently maintained over 12-24 weeks. Anamorelin, versus placebo, significantly increased body weight from baseline of original trials at all time points (P < 0.0001) and improved anorexia-cachexia symptoms at weeks 3, 6, 9, 12, and 16 (P < 0.05). No significant improvement in HGS was seen in either group. Conclusion: During the 12-24 weeks ROMANA 3 trial, anamorelin continued to be well tolerated. Over the entire 0-24w treatment period, body weight and symptom burden were improved with anamorelin.