Bioengineered blood vessels could see an early use aiding hemodialysis patients who have exhausted their vascular access options. Regenerative medicine startup Humacyte has disclosed Phase II data for its human acellular vessels (HAVs) to do just that–and it’s starting a 350-patient Phase III trial at 35 sites in the U.S., Europe and Israel. The Research Triangle Park, NC-based startup has plenty of cash for such a large trial–last fall it raised a whopping $150 million.
Ultimately, the bioengineered material used in these vascular grafts, which are known as Humacyl, is expected to be useful in a variety of indications including vascular trauma, coronary artery bypass, replacement trachea and esophagus and for bypass in peripheral arterial disease (PAD). The technology behind Humacyte came out of the famed Massachusetts Institute of Technology (MIT) lab of Dr. Robert Lander, who sits on the company’s board.
The Phase III trial is slated to have primary endpoint data by July 2017, according to Clinicaltrials.gov.
“Methods for establishing vascular access for dialysis are still inadequate, as evidenced by low rates of long-term patency and significant rates of infection among other complications,” said Humacyte CMO Dr. Jeffrey Lawson in a statement. “Humacyl is the first bioengineered tissue to advance to Phase III clinical studies for investigation in a life-sustaining use. Humacyl may offer a potential safe and effective alternative for vascular access in hemodialysis treatment and we are excited to begin this pivotal clinical trial.”
Humacyl vessels are made in a bioreactor from banked, human, vascular smooth muscle cells. They are decellularized to remove the cells and DNA. But they retain extracellular matrix proteins such as collagen, which are the same across humans. The process preserves the mechanical properties of the vessel. The vessels do not require any tissue from the recipient patient and are stored in refrigeration until being implanted in the operating room.
Data for the 60-patient Phase II trial of Humacyl vessels was published in The Lancet. It found that their use resulted in adequate blood flow rates for hemodialysis and that there was no immune reaction in any patient. There was one infection in the study that was attributed to Humacyl.
The HAVs did not show any structural degeneration over an average of 16 months of follow-up in 60 patients. In fact, histological evidence showed that Humacyl was becoming repopulated with host cells–suggesting that overtime it may function as a scaffold to be remodeled with host tissue.
Hemodialysis patients typically turn to synthetic material grafts when they are no longer candidates for new or replacement fistulas, the typical access point for hemodialysis. But these synthetic grafts can become blocked over time and infected–requiring ongoing interventions or hospitalizations to remain functional.
Other biological alternatives for dialysis access have been studied, but none have shown long-term viability the company noted. There are more than 400,000 people with end-stage renal disease undergoing hemodialysis in the U.S. alone.
“The results of Humacyte’s Phase II clinical studies provide further evidence that this human acellular vessel could have significant impact on patients who are undergoing dialysis, and who require long-term, viable vascular access,” said Lawson. “The results mark a major milestone in vascular therapy and in the field of regenerative medicine.”