A recent clinical trial, published in the journal Pediatric Drugs, has found that a combination of sildenafil and milrinone has proven effective in treating severe persistent pulmonary hypertension (PH) in newborns.

In infants, the circulatory system undergoes significant changes when they transition away from relying on the placenta for blood circulation and oxygen.

When newborns fail to make this transition and do not get enough oxygen, they develop severe persistent pulmonary hypertension (PPHN).

Newborns with PPHN ideally receive either inhaled nitric oxide or extracorporeal membrane oxygenation (ECMO), but they are not widely available due to high costs.

PDE5-inhibitors like sildenafil, sold under the name Revatio for PH in adults, and a heart failure medicine like milrinone, marketed as Primacor, have emerged as an effective and less expensive treatment for PPHN in newborns.

A team of researchers from Alexandria University, Egypt, investigated the safety and efficacy of both sildenafil and milrinone together.

The study participants were divided into three groups – the first group received only sildenafil, the second received only milrinone, and the third group received both sildenafil and milrinone.

The researchers found that the third group had an improvement in pulmonary artery systolic pressure (PASP) than the other two groups.

Findings showed that PASP values dropped significantly in the group that received both the drugs right from the start to the end of the study. In the other two groups, PASP values remained unchanged.

The oxygenation index also decreased significantly in the group that received sildenafil and milrinone.

Furthermore, the combined therapy group had the lowest mortality rate than the other two groups.

The researchers wrote, “Combined therapy with oral sildenafil and intravenous milrinone had significantly better outcomes than monotherapy with either agent in neonates with PPHN,” recommending this combination of sildenafil and milrinone to be used “in resource-constrained settings.”

However, they concluded, “Future trials with longer durations and more patients are needed to confirm the benefits and evaluate the neurodevelopmental effects of the different treatment modalities in these patients.” The article originally appeared on Pulmonary Hypertension News.