Selexipag (Uptravi) does not change the level of daily activity of patients with pulmonary arterial hypertension (PAH), results from the phase 4 TRACE trial suggest.
“We had no preconceived idea if this drug would improve exercise capacity,” said Luke Howard, MD, of Imperial College Healthcare NHS Trust in London. It was clear, however, that 6-minute walk tests conducted a few times a year “don’t paint a picture of what daily life is like for patients on selexipag.”
The oral prostacyclin IP receptor agonist is prescribed to slow the progression of PAH and reduce hospital admissions, but there are no studies that show whether it improves quality of life.
Dr. Howard and his team turned to wearable technology to “capture a snapshot of everyday life,” he explained during his presentation at the annual meeting of the American College of Chest Physicians (CHEST 2020), held virtually this year.
The primary concern of the investigators was to get TRACE participants – all with PAH – to wear a wrist device; they did not encourage patients to become more active. “We wanted a true picture of the impact of the drug itself,” he noted.
After 24 months of daily tracking, “there was no benefit to increased daily activity for patients taking this drug,” Dr. Howard said in an interview. “That was a bit deflating.”
The daily activity of TRACE participants was “slightly more elevated” in the selexipag group than in the placebo group. “We saw some numerical drops in activity in the placebo group, and a trend that might make a difference over a longer, bigger study, but not in a statically significant way,” he reported.
In the randomized, blinded trial – the first to track the activity of PAH patients – 53 participants received selexipag and 55 received placebo. All 108 wore a wrist accelerometer (GT9X Link) that counted the number of steps taken each day, providing an indication of daily activity.
Device compliance – the mean number of days in which the device was worn for at least 7 hours during a 14-day predrug period – was similar in the selexipag and placebo groups (13.2 vs 13.0 days).
“We wanted to make sure we had people who were stable and weren’t enrolled in a rehabilitation program; we didn’t want any competing influences,” Dr. Howard explained. All in all, the participants were in pretty good shape. “There was a low risk of a bad outcome.”
The primary endpoint was change in activity from baseline to week 24. The secondary endpoints were PAH-SYMPACT health quality-of-life tests and 6-minute walk distance.
Similar activity levels in both groups
As expected in a population in which the majority of patients meet the criteria for WHO functional class II PAH, all participants had low PAH-SYMPACT domain scores throughout the trial.
All adverse events were “consistent with the known profile” of selexipag, and there were no deaths, Dr. Howard reported.
“We did not show any significant benefit to taking the drug,” he said, but the drug is marketed for the prevention of disease progression, and this finding “doesn’t change that.”