Bioresorbable polymer-based drug-eluting stents (BP-EES) are comparable to durable polymer-based drug-eluting stents (DP-ZES), according to results from TRANSFORM-OCT.
The findings were presented Nov. 2 at the 28th annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium in Washington, D.C.
To mitigate the risk related to durable polymer (DP), bioabsorbable polymers (BP) that coat only the abluminal side of the stent, avoiding contact with circulating blood, and render stent surface similar to those of BMS after complete absorption, have been developed. Whether BP abluminal coating may counteract in-vivo delayed healing and NA development in current thin-strut DES is unknown.
TRANSFORM-OCT randomized 90 patients with multivessel disease to a BP-EES or a DP-ZES. The primary endpoints were maximum length of consecutive frames with uncovered struts at three months and the percentage of patients presenting with frames of neoatherosclerosis (NA) at 18 months as measured by OCT. The three-month median percentage of covered struts was 79 percent for BP-EES and 78 percent for DP-ZES.
The 18-month median percentage of covered struts was 99 percent for BP-EES and 98 percent for DP-ZES. The co-primary endpoint of in-stent NA at 18 months from 98 percent of all eligible patients was 11 percent for BP-EES versus 16 percent in DP-ZES with low percentage of frames with NA in both stent types.
“In this head-to-head in-vivo comparison of early and late healing response, the bioresorbable abluminal polymer Synergy everolimus-eluting stent was non-inferior at 3-month and similar at 18-month follow-up to the durable conformal polymer Resolute zotarolimus-eluting stent,” Giulio Guagliumi, MD, with Ospedale Giovanni XXIII in Bergamo, Italy said in a statement. “TRANSFORM-OCT adds a novel mechanistic dimension to the assessment of new-generation drug-eluting stents, consolidating the understanding that well designed and biocompatible polymers, regardless of whether they are durable or biodegradable, may favorably impact the long-term vascular response of these stents.”