Pulmonary Hypertension Patients Like Implanted Remodulin Delivery System

Pulmonary arterial hypertension (PAH) patients have given high marks to a new implanted,  programmable intravenous (IV) system that delivered Remodulin (treprostinil) to them with few complications, according to a clinical trial.

The study, “Treprostinil Administered to Treat Pulmonary Arterial Hypertension Using a Fully Implantable Programmable Intravascular Delivery System Results of the DelIVery for PAH Trial,” was published in the journal Chest.

Remodulin is a prostanoid, or biologically active lipid involved in inflammatory responses. The lipids can improve symptoms and outcomes in patients with advanced PAH.

Patient and physician dissatisfaction with prostanoid delivery has limited the therapies’ use, however. Many patients feel pain where an IV catheter is attached, and a catheter can lead to bloodstream infections.

Researchers at the University of Alabama at Birmingham, led by Dr. Robert C. Bourge, decided to test an implanted, programmable IV delivery system. They called the multicenter prospective clinical trial they conducted DelIVery (NCT01321073).

The 60 patients in the study used implanted Medtronic Model 10642 catheters to receive a stable dose of IV Remodulin for at least four weeks. All of the patients had severe PAH, which meant they fell into the World Health Organization group 1 category.

Researchers refilled the Remodulin in the implanted pumps through the skin at least once in every 12 weeks. The primary focus of the analysis was how many catheter-related complications the Medtronic device would cause. Complications were defined as adverse events requiring invasive intervention.

Patients were followed an average of 12 months. Intermediate assessments were done at six weeks, three months and six months after implantation.

Researchers found six catheter-related complications at six months. The complication rate of 0.27 per 1,000 patient days was significantly lower than the rate of 2.5 per 1,000 patient-days that previous studies had documented.

The scientists did not find any catheter-related bloodstream infections or catheter occlusions — gas trapped in a catheter.

Sixteen complications unrelated to the catheter were detected. Complications related to catheters being dislodged were minimized by additional training of medical staff. Three patients died during the study, but the causes of their deaths were unrelated to Remodulin treatment or the delivery system.

Another finding was that patients were able to spend significantly less time managing the implantable system within six months of receiving it. Every patient rated the delivery system good, very good, or excellent at six weeks and six months.

Seventy-nine percent of patients said during a six-month assessment that the treatment was more effective than they had expected.

Researchers found a high correction between plasma levels of Remodulin a week after implantation and levels before implantation, suggesting the delivery system quickly achieved the target dose. The research team detected no significant changes in patients’ exercise capacity or quality of life.

A limitation of the study was lack of a control group receiving Remodulin through an external pump. In addition, the research team limited enrollment to patients who had already been receiving a stable dose of Remodulin and had shown they could tolerate it. This precluded the researchers from being able to recommend the delivery system for those in the early stages of PAH treatment.

Nonetheless, the team concluded that “the implantable intravascular delivery system delivered treprostinil to patients with PAH with a low rate of catheter-related complications and a high rate of patient satisfaction.” The results suggest that the system “may be an important new option for patients with PAH who require parenteral treprostinil,” they wrote.