August 11th, 2009
The National Heart, Lung and Blood Institute (NHLBI) has halted a clinical trial involving drug treatment tests for pulmonary hypertension in adults who suffer from sickle cell disease. The trial comes to a premature end after only one year of study, due to safety concerns. These concerns come after a 16 week interim review was conducted of the 33 participants. Researchers discovered that participants actively taking sildenafil (Revatio), were experiencing an increase in consequential medical problems, versus the placebo participants. The most common effect were episodes of severe pain (sickle cell crisis), which required hospitalization for the participants. No deaths has occurred during the clinical trial.
Sickle cell disease is one of the most prevalent genetic blood disorders in the U.S. Pulmonary hypertension is an immobilizing high blood pressure condition that effects the arteries, potentially leading to heart failure and death. Approximately, 30 percent of sickle cell patients are expected to develop pulmonary hypertension.
The study coined walk-PHaSST, was the first of its kind to involve a multi-center, randomized clinical trial, intent on testing the the safety and effectiveness of sildenafil for sickle cell disease patients who have also developed pulmonary hypertension.
NHLBI Director Elizabeth Nabel M.D., reminds the public that because the walk-PHaSST medical problems were individually specific to sickle cell disease patients, these findings “should not be applied to other groups of patients with pulmonary hypertension where the drug has been found to be safe and effective.”
