Sildenafil for pediatric pulmonary arterial hypertension

Barst JR and associates checked in on the role of oral sildenafil citrate in the treatment of pediatric pulmonary arterial hypertension [A Randomized, Double-Blind, Placebo-Controlled, Dose-Ranging Study of Oral Sildenafil Citrate in Treatment-Naive Children with Pulmonary Arterial Hypertension. CIRCULATIONAHA.110.016667 Published online before print November 29, 2011,doi: 10.1161/?CIRCULATIONAHA.110.016667]. Sildenafil is a phosphodiesterase V (PD5) inhibitor which is known to reduce pulmonary hypertension. Two hundred and thirty five children between the ages of one to seventeen years were enrolled in the STARTS-1 trial. It was a randomized placebo controlled trial in in which sildenafil was given orally thrice daily for four months. The main comparison was the effect on peak oxygen consumption (pVO₂). Exercise testing was done in one hundred and fifteen of the children. Secondary end points were hemodynamics and functional class. Peak oxygen consumption, functional class and hemodynamics improved in those who were on medium and high doses while the low dose was found to be ineffective. Those who completed STARTS-1 could enter the STARTS-2 extension study in which patients already on sildenafil continued it in the same dose while those on placebo were randomized to low, medium or high dose sildenafil as in STARTS-1 study group. In the STARTS-2 study which is ongoing, increased mortality was observed with high dose versus lower dose groups. The authors concluded that with overall combined data, it favours medium dose therapy with sildenafil.