NeurAxis has built a small but real revenue base (over 80% year-over-year growth) around a single cleared indication, functional abdominal pain in adolescents, before expanding label scope, a narrower commercialization path than most neuromodulation companies attempt at this stage. Its PENFS technology targets brain pain-processing regions like the amygdala via cranial nerve stimulation, giving it a gut-brain mechanism distinct from vagus-nerve-focused peers like Aurenar.