When a traumatic injury occurs to an artery, if a patient’s own veins aren't available for use as a bypass graft, they’ll typically have to be treated either with a synthetic implant or with surgical ligation or amputation—all while doctors attempt to avoid the infections common among easily contaminated wounds.
Humacyte has taken a step closer to a better, safer approach: The company on Tuesday unveiled results from a phase 2/3 trial showing that its Human Acellular Vessel (HAV) could outperform synthetic grafts in patency as well as future amputation and infection rates.
The HAVs are bioengineered, regenerative human tissues that are meant to be universally implantable, meaning they could ultimately be used off-the-shelf to treat traumatic injuries in addition to peripheral artery disease and other conditions, as well as to help create an arteriovenous access ports for hemodialysis procedures.
The V005 trial is a single-arm study that recruited 69 patients in the U.S. and Israel who had arterial injuries caused by gunshots, workplace injuries, car accidents and other traumatic events—51 of whom had been injured in their extremities, and none of whom had a large vein from the leg available for a standard bypass graft.
A month after being implanted with the HAVs, according to Humacyte’s release, secondary patency rates reached 90.2% for the extremity injury group—who made up the study’s primary evaluation group—and just under 90% for the total participant pool. Secondary patency, defined as a measure of good blood flow through the graft, was used as the principal means of evaluation in the study; historically reported benchmark data for synthetic grafts places their secondary patency around 81%.
Meanwhile, amputation rates also improved with HAV use: By the 30-day mark, only about 10% of both the extremity-only and total study groups required amputation, compared to a rate of 20.6% in the synthetic graft benchmark data.
Infections also dropped—from almost 9% among those implanted with synthetic grafts to 2.9% among all study participants and just 2% among those with extremity injuries.
No unexpected safety signals associated with HAV cropped up in the study, Humacyte said in the release, and CEO Laura Niklason, M.D., Ph.D., added, “We are elated that the V005 results support our expectation that the HAV may improve the treatment and outcome of patients suffering major traumatic injuries.”
Next up, Niklason noted, Humacyte will wrap up the process of filing a Biologics License Application with the FDA for this specific use of its HAVs—after which, if the BLA is granted, the company will be able to begin the commercial rollout of the tissues for extremity vascular repair following traumatic injuries.
The company is aiming to submit the BLA to the FDA before the end of this year. Its application is eligible to receive priority review since the HAV received the agency’s Regenerative Medicine Advanced Therapy designation earlier this year.
Humacyte also noted in the release that the FDA has advised it to include in the BLA submission a summary of results from the HAVs’ recent real-world humanitarian use in Ukraine. Among the 16 extremity patients included, 30-day secondary patency reached nearly 94%, with no amputations needed and no infections reported.