June 13, 2003

Zapol and former colleague receive Inventor of the Year award

Warren M. Zapol, MD, (right), chief of MGH Anesthesia and Critical Care, and Claes Frostell, MD, PhD, of theKarolinska Institute in Sweden, received the 2003 Inventor of the Year award June 4 in Washington. The researchers were honored for their invention of a system to safely deliver inhaled nitric oxide gas to treat a number of dangerous lung conditions.

"I was stunned to learn that we had received this year's award," says Zapol. "I regard myself as a clinician-scientist rather than an inventor. But I can certainly see why they chose to recognize inhaled nitric oxide. It has saved the lives of thousands of "blue" babies and others with pulmonary hypertension in this country and around the world, which has been rewarding enough for me."

The award has been presented annually since 1974 by the Intellectual Property Owners Association (IPO). Among previous recipients of the award are Paul Macready for the "Gossamer Condor," a human-powered flying device; Robert Jarvik for the Jarvik Seven artificial heart; James L. Fergason for liquid crystal displays; and Amar G. Bose for a folded waveguide loudspeaker system.

For many years, nitric oxide (NO) gas — not to be confused with the anesthetic nitrous oxide — was considered a dangerous pollutant. Then in the mid-1980s three U.S. researchers discovered that the human body naturally uses NO to transmit key signals in the pulmonary, cardiovascular and other systems, a discovery that led to the 1998 Nobel Prize in Medicine or Physiology. Subsequent NO studies showed that among its many functions was to relax the muscles surrounding blood vessels and reduce blood pressure. Because many serious medical conditions are characterized by constriction of blood vessels in the lungs, Zapol and several MGH colleagues began to study its potential as a treatment.

Zapol worked with Frostell, at the time a postdoctoral research fellow at the MGH, to develop a system to continuously administer a low concentration of NO in oxygen. Once this equipment was perfected, animal studies showed that inhaled NO opened only constricted lung vessels and had no effect on vessels that were normal.

Zapol, left, and Frostell, far right, with families of children saved by NO treatment.

The first clinical application studied at the MGH was the treatment of a rare, potentially fatal disease — persistent pulmonary hypertension of the newborn (PPHN) — in which blood vessels in infants' lungs do not expand soon after birth. Several MGH studies led by Jesse Roberts, MD, showed that inhaled NO could rapidly and effectively treat PPHN, turning babies that were blue from lack of oxygen to a healthy pink in a matter of minutes.

In 1999 the U.S. Food and Drug Administration approved inhaled NO for the treatment of PPHN and other hypoxic respiratory failure in newborns. The treatment also is used to improve lung circulation in infants after surgery for congenital heart disease and to help diagnose pulmonary hypertension in adults. Ongoing NO research at the MGH and other centers includes investigating its use in infants with pulmonary vascular disease and to treat painful sickle cell crisis.