Developers of a cutting-edge lab-grown blood vessel designed to save life and limb in war zones and other emergency scenarios appear to be promoting its use in surgeries far beyond the product’s approved scope. The “off-label” use of these bioengineered tissues comes despite indications of questionable efficacy and potentially catastrophic ruptures.

The biotechnology firm, Humacyte, has developed an artificial blood vessel, called Symvess, that was approved by federal regulators for use in adults with trauma to their arms or legs who urgently need new arteries “to avoid imminent limb loss.”

But at a premier vascular surgery conference this November, Humacyte promoted research presentations on alternative uses of its vessels from a clinical trial — part of a growing trend of “off-label” uses of medical devices.