FDA Approves Symvess for Treatment of Extremity Vascular Trauma

Key Takeaways

Symvess is an FDA-approved acellular tissue-engineered vessel for urgent revascularization in extremity arterial injuries when autologous vein grafts are not feasible.
The V005 trial showed high primary patency (84.3%) and secondary patency (90.2%) rates, with low infection and amputation rates.
Symvess offers an off-the-shelf solution, reducing surgical time and potential patient harm, and is expected to revolutionize vascular trauma care.
Adverse events in the V005 trial were consistent with other vascular conduits, with acceptable rates of thrombosis, rupture, aneurysm, and pseudoaneurysm.

The approval follows positive results from the V005 (NCT03005418) clinical trial.

The FDA approved acellular tissue engineered vessel-tyod (Symvess, Atev; Humacyte Inc) for use in adults as a vascular conduit for extremity arterial injury when urgent revascularization is needed to avoid imminent limb loss and when autologous vein graft is not feasible.¹ The approval follows positive results from the pivotal phase 2/3 V005 (NCT03005418)² clinical trial.

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About the Trial

Trial Name: Humacyte Human Acellular Vessel (HAV) in Patients With Vascular Trauma

ClinicalTrials.gov ID: NCT03005418

Sponsor: Humacyte, Inc.

Completion Date (Estimated): September 1, 2027

Symvess is a first-in-class bioengineered human tissue that is designed to be a universally implantable vascular conduit for use in arterial replacement and repair. Because harvesting vein from a trauma patient can take time during surgery, Symvess is available off-the-shelf, which does not require potential further injury to the patient to obtain vascular repair material via an invasive surgery. The Symvess trauma program was granted regenerative medicine advanced therapy designation by the FDA in May 2023, and in February 2024, it received a priority review.¹

“The approval of a vascular conduit that resists infection and remodels into native arteries is an extraordinary technological advancement that will have a huge impact on the quality of trauma care around the world,” Charles J. Fox, MD, FACS, director of Vascular Surgery at the University of Maryland Capital Region, said in a news release. “Symvess is perfectly sized to treat most injuries, has excellent handling properties, and reduces time necessary to save both life and limbs.”¹

The V005 (NCT03005418) trial, also called CLN-PRO-V005, is a prospective, multicenter, multi-cohort, non-randomized phase 2/3 study which enrolled patients with life- or limb-threatening vascular trauma which requires surgical repair. A limb cohort includes patients who require repair of a vessel contained to the upper or lower extremity, and a torso cohort includes patients who require repair of vessels within the thorax (excluding the heart), abdomen, and retroperitoneum. No control arms are included in this study.²

All patients received the investigational Symvess, which were used for arterial bypass or reconstruction. The device is implanted using a standard vascular surgical technique, similar to those used to place predicate peripheral vascular prostheses. The primary outcome measures are primary patency (defined as the interval from the time of access placement until any intervention designed to maintain or reestablish patency, access thrombosis or the measurement of patency), which was assessed at 30 days, and frequency and severity of adverse events (AEs), which was assessed at 36 months.²

A total of 69 patients with a mean age of 33.5 years were enrolled in the trial, of which the majority were male (n = 38). At day 30, the primary patency was approximately 84.3% (95% CI, 72.0%-91.8%) and secondary patency was 90.2% (95% CI, 79.0%-95.7%). Additionally, amputation rate was about 9.8% (95% CI, 4.3%-21.0%). Infection and death rates were also low, occurring in about 2.0% (95% CI, 0.4%-10.3%) and 5.9% (95% CI, 2.0%-15.9%) of patients, respectively.³

“I believe that Symvess will revolutionize vascular trauma care and be profoundly beneficial to our patients,” Rishi Kundi, MD, surgical critical care of vascular surgery at the University of Maryland Medical System, said in the news release. “From my experience so far, Symvess will allow reconstructions that are currently impracticable because of contamination and infection. It will make reconstructions that we now perform with prosthetic or even biologic grafts more successful.”¹

Overall, AEs and serious AEs were frequent in V005 consistent with patients with acute injuries. According to the investigators, AEs of special interest, including thrombosis, rupture, aneurysm, and pseudoaneurysm, occurred at acceptable rates that were consistent with reports of other vascular conduits, including autologous vein and synthetic grafts. At 30 days, AEs of interest were reported for 8 patients and included thromboses and occlusions (resolved or unresolved), nonspontaneous rupture (n = 1), and infection of the conduit (n = 1). Additionally, all enrolled patients receiving Symvess presented multiple risk factors that could lead to wound infection, of which 20 patients developed 1 or more infectious events by day 30 (eg, bacteremia, fungemia, sepsis, and osteomyelitis).³

“The FDA approval of Symvess will make it the preferred conduit for complex vascular injuries, and particularly those at risk for infection,” Ernest E. Moore, MD, FACS, director of Research at the Ernest E. Moore Shock Trauma Center at Denver Health, said in the news release.¹

REFERENCES

1. GlobeNewswire. Humacyte Announces FDA Approval of SYMVESS™ (acellular tissue engineered vessel-tyod) for the Treatment of Extremity Vascular Trauma. News release. December 19, 2024. Accessed December 20, 2024. https://www.globenewswire.com/news-release/2024/12/20/3000367/0/en/Humacyte-Announces-FDA-Approval-of-SYMVESS-acellular-tissue-engineered-vessel-tyod-for-the-Treatment-of-Extremity-Vascular-Trauma.html

2. Humacyte Human Acellular Vessel (HAV) in Patients With Vascular Trauma. ClinicalTrials.gov identifier: NCT03005418. Updated November 2, 2023. Accessed December 20, 2024. https://clinicaltrials.gov/study/NCT03005418

3. Moore EE, Curi M, Namias N, et al. Bioengineered Human Arteries for the Repair of Vascular Injuries. JAMA Surg. Published online November 20, 2024. doi:10.1001/jamasurg.2024.4893