Two researchers who study the debilitating sleep disorder have won a prestigious Lasker Award. Their research in animals laid the groundwork for a new drug that addresses the condition’s root cause. In the late 1990s, Dr. Masashi Yanagisawa at the University of Texas Southwestern Medical Center discovered two brain chemicals in rodents that seemed to be instrumental in stimulating hunger.

He called them “orexins,” a play on “orexis” the Greek word for appetite. At the same time, Dr. Emmanuel Mignot at Stanford University School of Medicine was hunting for the root cause of an inherited form of narcolepsy in Doberman pinschers, Labrador retrievers and Dachshunds. In back-to-back studies published in the summer of 1999, these two lines of research unexpectedly converged, breaking open the neurobiology of sleep and identifying a root cause of the sleep disorder narcolepsy, which affects an estimated one in every 2,000 people in the United States.

A new narcolepsy drug based on these insights was approved in August. On Wednesday, Dr. Yanagisawa, now at the University of Tsukuba in Japan, shared the Albert Lasker Basic Medical Research Award with Dr. Mignot, for their work into the nature of sleep. The prestigious prizes are often called “America’s Nobel.”.