In 2001, CNTF was reported that in a human study examining the usefulness of CNTF for treatment of motor neuron disease, CNTF produced an unexpected and substantial weight loss in the study subjects. Further investigation revealed that CNTF could reduce food intake without causing hunger or stress, making it a candidate for weight control in leptin resistant subjects, as CNTF is believed to operate like leptin, but by a non-leptin pathway.