Bioengineered Liver Offers Hope in Acute Liver Failure Trial

SILVER SPRING, Md. – January 26, 2026 – In a significant step toward addressing one of medicine's most urgent challenges, United Therapeutics Corporation has announced positive results from the first human clinical trial of miroliverELAP®, an external, bioengineered liver. The Phase 1 study demonstrated the safety of the device in patients with acute liver failure (ALF), a rapidly progressing condition with a grim prognosis for those unable to secure a transplant.

The news offers a potential lifeline for thousands of patients who face a desperate race against time, providing a "bridge" that could allow their own liver to recover or buy precious time to find a suitable donor organ.

A Bridge to Life for Patients in Crisis

Acute liver failure is a devastating diagnosis. It strikes suddenly, causing a rapid loss of liver function over days or weeks. While the liver has a remarkable capacity for regeneration, many patients deteriorate too quickly. Annually, tens of thousands in the U.S. are hospitalized with severe forms of liver failure. For these individuals, the only definitive treatment is a liver transplant. However, a severe shortage of donor organs means this option is unavailable to many. Approximately 30% of ALF patients die because they are ineligible for a transplant or an organ does not become available in time.

The miroliverELAP® study targeted this exact population: five patients with ALF who were not candidates for a transplant. Each was treated continuously with the external device for at least 44 hours. The study successfully met its primary safety endpoint, with all patients surviving the treatment period. Crucially, no unexpected serious adverse events attributable to the device were reported during a subsequent 32-day follow-up.

“This study provides early evidence that miroliverELAP, an innovative bioengineered organ alternative product, has the potential to provide liver support for patients experiencing ALF, giving their native livers more time to recover,” said Jeff Ross, Ph.D., President of Miromatrix, the United Therapeutics subsidiary that developed the technology. “Achieving this important milestone allows us to continue advancing miroliverELAP to help save and improve the lives of ALF patients, who face poor outcomes and a desperate need for therapies.”

The Science of a Bioengineered Organ

The technology behind miroliverELAP® represents a landmark achievement in regenerative medicine. The process begins with a porcine (pig) liver, which is put through a proprietary perfusion decellularization process. This gentle washing technique removes all the pig cells while preserving the intricate and essential extracellular matrix (ECM)—the natural scaffold that gives the organ its shape and vascular structure. This porcine scaffold is remarkably similar to a human one, with over 93% homology, minimizing the risk of adverse immune reactions.

This pristine, cell-free scaffold is then brought back to life in a bioreactor. In a process called recellularization, it is carefully seeded with human liver cells (hepatocytes) and endothelial cells, which line the blood vessels. These cells are sourced from donated human livers that were deemed unsuitable for transplantation, turning what would have been discarded tissue into a life-saving component.

Once prepared, the bioengineered liver is housed in an external device, the miroliverELAP® system. The patient's blood is circulated outside the body, through the bioengineered organ, which performs critical liver functions like filtering toxins and producing essential proteins. This external support system is designed to stabilize the patient, mitigating the cascading effects of liver failure.

A Bold Vision Beyond Traditional Transplants

This successful trial is a key validation of the broader mission of United Therapeutics. As a public benefit corporation (PBC), the company is legally committed to a dual purpose: developing novel therapies and creating technologies to expand the availability of transplantable organs. The miroliverELAP® is a cornerstone of its allogeneic regenerative medicine platform, one of three parallel strategies the company is pursuing to end the organ shortage.

The other platforms include xenotransplantation—the use of genetically modified pig organs for human transplant—and autologous regenerative medicine, which uses a patient's own cells. This multi-pronged approach tackles the organ crisis from several angles, with programs underway for hearts, kidneys, and lungs in addition to livers.

“United Therapeutics is committed to developing technologies that expand the availability of transplantable organs, and the completion of this clinical trial represents yet another historic achievement for our company,” said Martine Rothblatt, Ph.D., Chairperson and Chief Executive Officer of United Therapeutics. “We are thrilled to see positive results from this groundbreaking study of miroliverELAP in ALF patients for whom liver transplantation was not an option.”

This strategy extends to developing fully transplantable organs. Using the same decellularization and recellularization technology, Miromatrix is also developing mirokidney®, a bioengineered kidney intended for full implantation.

Navigating the Path to a New Standard of Care

The journey for miroliverELAP® from the lab to the clinic has been a meticulous one, navigating a complex regulatory landscape. Miromatrix received Investigational New Drug (IND) clearance from the U.S. Food and Drug Administration (FDA) in 2024 to begin the trial, a significant milestone for a bioengineered organ. The path forward will involve larger clinical trials to confirm the safety and demonstrate the efficacy of the device in improving patient outcomes.

While United Therapeutics is a clear frontrunner, the field of liver support is active. Researchers at institutions like Carnegie Mellon University are exploring 3D bioprinting to create temporary liver patches, and other companies are developing different types of bioartificial liver (BAL) devices. However, the success of miroliverELAP® in its first human trial marks a critical real-world advance for a technology that has long been a subject of futuristic speculation.

For the patients, physicians, and organ procurement organizations who participated in this landmark study, the results represent more than just data. They signal the dawn of a new era in which manufactured organs can supplement the scarce supply of donated ones, offering tangible hope where there was once very little. The full, detailed results from the Phase 1 study are expected to be presented at scientific conferences and published in medical journals in the second half of 2026, providing the medical community with a deeper understanding of this pioneering therapy.