Nov. 16, 2005 -- A drug called Revatio may help treat an aggressive condition called pulmonary arterial hypertension.
Patients with pulmonary hypertension have elevated blood pressure in the pulmonary (lung) blood vessels. The condition often arises from lung problems, but some cases are without a known cause. It can result in heart failure and early death.
Unfortunately, most of the medications that are used to treat this serious condition are not easy to take and are given by IV, injection, or inhalation -- with real risks of unwanted side effects.
Revatio has the same active ingredient -- sildenafil -- as Viagra. Revatio and Viagra are made by Pfizer.
Pfizer funded the new study, which appears in The New England Journal of Medicine. Pfizer is a WebMD sponsor.
The researchers included Nazzarene Galie, MD, of the cardiology institute at Italy's University of Bologna.
The study lasted for 12 weeks. It included 278 patients with pulmonary hypertension. The patients lived in the U.S., Mexico, South America, Europe, Asia, Australia, South Africa, and Israel.
Three times daily, the patients took Revatio (20, 40, or 80 milligrams) or an empty drug (placebo) orally. That was in addition to any other standard pulmonary hypertension medications.
The big question was how far patients could walk in six minutes. That's an important exercise test for patients with pulmonary hypertension. The farther patients can walk, the better.
All of the patients taking Revatio walked farther at the end of the study:
- 20-milligram group: Walked about 148 extra feet (a 13% increase).
- 40-milligram group: Walked about 151 extra feet (a 13% increase).
- 80-milligram group: Walked about 164 extra feet (nearly a 15% increase).
Higher doses didn't bring a notable increase in distance walked, the researchers report.
Patients were then allowed to take Revatio for up to a year; 230 did so. The researchers looked at the walking tests of 222 of those who were only taking Revatio as treatment. After a year, they walked about 167 extra feet, on average, compared with the beginning of the study.
How Patients Fared
Most of the patients included in the study had milder stages of pulmonary hypertension. Few cases worsened, regardless of treatment type, the study shows.
Patients taking Revatio weren't any more or less likely to have their symptoms worsen during the trial.
The study wasn't designed to see if Revatio helped patients live longer. Four died during the study. No deaths were judged to be linked to the treatments, write the researchers.