The successful treatment of a patient with pulmonary arterial hypertension who contracted COVID-19 with self-administered inhaled nitrous oxide from a tankless device at home has caught the imagination of researchers investigating treatments for other patients.
It is not clear whether the team was treating the COVID or “some manifestation of her pulmonary hypertension exacerbation,” said Roham Zamanian, MD, a pulmonologist at Stanford Health in Palo Alto, California.
This is why a clinical trial is needed, he told Medscape Medical News.
“In this case, the COVID-19 respiratory infection led to a pulmonary hypertension exacerbation,” he explained. And the 34-year-old woman, who is also a physician, had demonstrated a response to nitric oxide before contracting the COVID-19 virus.
Zamanian and his colleagues describe the case in a letter published online in the American Journal of Respiratory and Critical Care. It will be discussed at the upcoming American Thoracic Society 2020 International Conference.
COVID-19 was confirmed in the patient, who had stable vasoreactive idiopathic pulmonary arterial hypertension, after she returned from a trip to Egypt. She did not want to travel the 350 miles from her home to the hospital for treatment, potentially infecting others, unless it was absolutely necessary.
“We had to make sure we were doing the right thing treating her at home, and we had to do it quickly,” Zamanian said. The patient was put on a remote routine – with vital monitoring in place – that included 6-minute walk tests twice daily and video conferencing. She also completed the EmPHasis-10 questionnaire, which is used to assess the status of patients with pulmonary hypertension.
The care team filed an Emergency Investigational New Drug application for the off-label at-home use of the tankless inhaled nitric oxide system (GENOSYL DS, VERO Biotech), which was approved by the US Food and Drug Administration. The system has so far been approved only for the treatment of newborns with persistent pulmonary hypertension.
Off-label inhaled nitric oxide has never been used in an outpatient setting. “That’s where this case is unique,” Zamanian explained.
“This case was very specific. We knew she was vasoreactive, and she knew how to use the device,” he said. “And we know nitric oxide is a quick-acting medication when it works, showing results in minutes, if not seconds.”
Within 24 hours of approval, the tankless system arrived at her home.
The patient’s therapy consisted of nitric oxide at a dose of 20 ppm plus supplemental oxygen delivered by nasal cannula at a dose of 2 L/min for 12 to 14 hours a day. After symptomatic improvement, a stepwise reduction in nitric oxide was implemented from day 13 to 17, with the dose dropping to 10 ppm, 5 ppm, and then 0 ppm.
“We quickly knew she was responding and feeling better. Without the medication, she would very likely have needed to be hospitalized,” Zamanian said.
“The real novelty of this case is demonstrating use in an outpatient system,” he pointed out. “My perspective is that this particular case was very specific, in a person who had been formally evaluated and known to be responsive to this treatment.”
The team is now preparing to launch a clinical trial of inhaled nitric oxide in COVID-19 patients without pulmonary hypertension, Zamanian reported.