ORLANDO, Fla.—Vonapanitase, an investigational drug being tested for use in promoting patency of radiocephalic fistulas, does not significantly improve primary patency in patients undergoing surgical creation of these fistulas, according to data presented at the National Kidney Foundation’s 2017 Spring Clinical Meetings. The drug, however, does significantly improve secondary patency and fistula use for hemodialysis (HD).
Vonapanitase is a recombinant human elastase that cleaves peptide bonds in elastin, the principal component of elastic fibers in blood vessels that impart elasticity. The drug is administered as a single local application to the external surface of the fistula immediately after creation.
“I was very encouraged by the results of the Patency-1 trial. While it did not meet its primary endpoint, there was a large, significant difference in fistula use, being 71% in the vonapanitase group and 48% in the placebo group,” said lead investigator Anthony J. Bleyer, MD, MS, of Wake Forest School of Medicine in Winston-Salem, North Carolina. “If such findings someday are translatable into the clinical realm, vonapantase, when approved, will have a huge clinical impact on the ability to use fistulas in our dialysis patients. This will significantly improve our patients’ quality of life and could also improve their survival.”
As part of the PATENCY-1 trial, Dr Bleyer and colleagues presented the results of a randomized prospective clinical trial comparing vonapanitase and placebo among 313 patients with chronic kidney disease on or expecting to initiate HD and who were undergoing surgical creation of a radiocephalic fistula. The primary endpoint was primary patency, defined as the time from fistula creation until first thrombosis or procedure to restore or maintain patency. Other endpoints included secondary patency, defined as the time from fistula creation until fistula abandonment, and fistula use for HD.
The primary patency rate at 12 months was 46% for vonapanitase and 34% for placebo, a nonsignificant difference. The secondary patency rate was significantly higher in the vonapanitase recipients compared with the placebo arm (80% vs 64%). The vonapanitase-treated patients had a 48% decreased likelihood of fistula abandonment compared with placebo patients. The rate of fistula use for HD also was significantly higher for the vonapanitase group than the placebo group (71% vs 48%).
The investigators defined fistula use for HD as the ability of the fistula to be successfully cannulated with 2 needles for a minimum of 90 days or at least 30 days and in use at patients’ last visit if HD had not been initiated at least 90 days prior to the last visit.
The trial was sponsored by Proteon Therapeutics, Inc., which is developing the drug.
See more coverage from the National Kidney Foundation Spring Clinical meeting.
Bleyer AJ, Kidd K, Wilson S, et al. PATENCY-1: A trial of topically applied vonapanitase to promote radiocephalic fistula patency and use for hemodialysis. Poster presented at the National Kidney Foundation’s 2017 Spring Clinical Meetings. Poster 379.