NEW YORK (Reuters Health) – A study from China indicates that vardenafil has favorable effects in patients with pulmonary arterial hypertension (PAH).
Dr. Zhi-Cheng Jing, at Tongji University School of Medicine in Shanghai, and colleagues note in their report in the American Journal of Respiratory and Critical Care Medicine online March 11 that sildenafil and tadalafil both produce improvements in PAH, but the benefits of monotherapy with these phosphodiesterase-5 inhibitors are uncertain.
The team investigated the effects of vardenafil monotherapy vs placebo in 66 patients with PAH. “No PAH-specific treatments (prostanoids, endothelin receptor antagonists or phosphodiesterase type 5 inhibitors) were allowed for at least 3 months prior to enrollment,” according to the report.
The participants were randomized 2-to-1 to receive 5 mg vardenafil once daily for the first 4 weeks, increasing to the target dosage of 5 mg twice daily (barring drug-related adverse events) or to matching doses of placebo.
After 12 weeks, the median 6-minute walking distance increased by 59 meters in the vardenafil group but decreased by 10 meters in the placebo group, the researchers found.
Vardenafil also increased the mean cardiac index at 12 weeks, with a difference of 0.39 L/min per m² between the active treatment and placebo groups. Mean pulmonary arterial pressure decreased, with a between-group difference of -5.3 mm Hg.
The mean Borg dyspnea index improved (-0.4) in the vardenafil group but deteriorated (+1.8) in the placebo group, the investigators report.
After 12 weeks, the 59 patients remaining in the trial entered a further 12-week extension trial of open-label vardenafil 5 mg BID. At 24 weeks, the improvement in 6-minute walking distance in the original vardenafil group was maintained (69 m increase from baseline), and a significant increase of 49 m from baseline was seen in the former placebo group.
A similar pattern was seen with the dyspnea index at 24 weeks.
The team found that headache and flushing were the most frequent side effects of vardenafil, but all adverse events were generally mild and transient.
“In conclusion,” Dr. Jing and colleagues write, “the favorable effects of vardenafil therapy on symptoms, exercise capacity, hemodynamics, and clinical outcome in treatment-naive patients with PAH and the relatively low cost of this medication suggest its usefulness as a first-line treatment in developing countries.”
Vardenafil in Pulmonary Arterial Hypertension: A Randomized, Double-blind, Placebo-controlled Study
Am J Respir Crit Care Med 2011.