A lab-grown blood vessel shortened catheter use for women on dialysis in an early-stopped trial

In Short. Women on dialysis given a lab-grown blood vessel spent about three fewer months on an infection-prone neck catheter than women given a standard surgical connection. The trial stopped early, and the lab-grown vessel clotted more often.

WHEN KIDNEYS fail, a machine can clean the blood instead. This treatment, hemodialysis, draws blood out and returns it, which requires a reliable way into the bloodstream. The quickest way in is a tube in a large neck vein, called a catheter. It works at once, but it carries a risk of infection. A 2025 review in Frontiers in Radiology put catheter bloodstream infections at 2 to 5 per 1,000 catheter-days, with a cumulative risk of 25% to 40% at one year.

The usual alternative is surgery, in which a surgeon joins an artery in the arm to a nearby vein, so that over several months the vein grows large enough to use. This connection, called a fistula, is the standard of care, but it sometimes never becomes usable. A 2021 review by researchers at Yale reported that fistulas in women take longer to mature, fail to mature more often than in men, and need more frequent repair procedures.

Humacyte, a company in North Carolina, grows a human blood vessel in a lab from cultured human cells, which are then removed to leave no living cells. The Food and Drug Administration (FDA) approved it in December 2024, as Symvess, for repairing injured blood vessels in the arms and legs. Its formal name is the acellular tissue engineered vessel, or ATEV.

The V012 trial, a late-stage study meant to support approval (phase 3), enrolled women on dialysis through a catheter whom surgeons judged suitable for a fistula. Women were assigned by chance, half to each option (randomized). The comparison group got fistula surgery, not a dummy treatment (an active control). Site teams knew which option each woman had, and only the committee judging outcomes was blinded (open-label). That matters because doctors who knew the assignment decided when catheters came out. The main measure, set in advance, was days without a catheter over a year (the primary endpoint). The registry lists a second primary measure, the rate of infections linked to any dialysis access. A planned early check came once the first 80 women had a year of follow-up (an interim analysis). The vessel met its goal there, so enrollment stopped at 121 women, against about 150 planned.

The results, presented at a kidney conference on October 22nd, cover 40 women in each group. Over 12 months, women given the vessel spent on average 220 days without a catheter, against 129 with a fistula. The difference of 91 days had a 95% confidence interval of 40 to 142 days, the range of differences consistent with the data (P<0.001). Days with a working access were 250 against 152, and the vessel became usable after about 1.7 months, against 5.3 months for the fistula. About two-thirds of fistulas had matured by month 12, Humacyte reports. Dialysis access infections, including those from catheters, were reported in about one in seven fistula patients and about one in twenty vessel patients. None was in the study vessel or fistula itself.

The results have limits. They rest on the first 80 of 121 enrolled women, at a planned early look. A trial halted when it reaches its goal gives less certainty about how large the gain really is, and the interval of 40 to 142 days is wide. The registry has posted no results.

The vessel also needed more upkeep. There were 20 clotting events (thrombosis) with the vessel against 8 with the fistula, and 43 narrowing events (stenosis) against 36. These count events, not women. Humacyte adjusts narrowing for how long each access was in use and reports a lower rate with the vessel, 162 against 229 per 100 patient-years. At six months, 88% of vessels and 65% of fistulas among those analyzed were still usable with repairs allowed (P=0.02). At 12 months the figures were 78% and 63%, a gap that was not statistically significant (P=0.16).

Most of the evidence comes from the sponsor. The October press release and a June company filing are Humacyte's own, and the conference abstract lists Humacyte as its commercial support and includes three Humacyte authors. The trial enrolled only women, followed them for only a year, so it cannot say how long the vessel lasts or whether men would benefit.

Humacyte says it plans to ask the FDA to extend the vessel's approval to dialysis access. Follow-up of all 121 women and the agency's review of the full data will show whether faster access to dialysis outweighs the extra clotting.