Merit Begins PREEMIE Study of Bloom Micro Occluder System

March 12, 2025—Merit Medical Systems, Inc. recently announced enrollment of the first patient in the PREEMIE study of the company’s Bloom micro occluder system for treatment of patent ductus arteriosus (PDA) in premature infants.

According to the company, the Bloom system was designed to be a minimally invasive option for treating hemodynamically significant PDA (hsPDA). Merit is evaluating the device through 6 months as part of its premarket approval application.

The PREEMIE study is a multicenter, prospective, investigational device exemption study of the Bloom system, which is not currently approved to treat PDA, noted the press release.

Merit stated that the PREEMIE study has been developed to evaluate the safety and efficacy of the Bloom device and is planned to enroll at least 55 premature infants with hsPDA at up to 10 sites in the United States. To be eligible, patients must weigh between 600 g (“extremely low birth weight”) and 2,500 g (“low birth weight”).

Howaida G. El-Said, MD, is the National Principal Investigator of the PREEMIE study and Director of the Cardiac Catheterization Laboratory at Rady Children’s Hospital in San Diego, California.

“As there is currently no approved device for PDA in premature infants as small as 600 g, we believe this study will provide critical information for treating this high-risk population,” commented Dr. El-Said in Merit’s press release. “Bloom’s versatile and softer device design may enable safer and more effective care for these fragile patients.”

Thomas J. Forbes, MD, an investigator in the PREEMIE study, added, “Options for transcatheter device closure of PDA are limited. This study is a potential game changer for pediatric interventional cardiologists, allowing us the option to more reliably perform procedures at bedside.” Dr. Forbes is Chief of Pediatric Cardiac Services at Joe DiMaggio Children’s Hospital in Hollywood, Florida.