The ACT‐ONE trial is a randomized, double‐blind, parallel group, placebo‐controlled, phase II multicentre trial in patients (25‐80 years) with stages III or IV colorectal cancer or non‐small cell lung cancer‐related cachexia that tested two doses of espindolol (a novel non‐selective β blocker with central 5‐HT1a and partial β2 receptor agonist effects). The gene discussed is HTR1A; the disease is lung cancer.