In addition, P2Y12 inhibitor monotherapy was almost equivalent to aspirin monotherapy after 3 months in terms of both bleeding and thrombotic events.
“Recent guidelines recommend short DAPT up to 3 months, only in high bleeding risk patients,” lead investigator Ken Kozuma, MD, said during a media briefing at the Transcatheter Cardiovascular Therapeutics annual meeting. “However, short-term DAPT may be beneficial for any patients. Aspirin may be more associated with bleeding complication than P2Y12 receptor inhibitors.”
In a single-arm registry trial known as MODEL U-SES, Dr. Kozuma, of Teikyo University Hospital in Tokyo, and colleagues at 65 sites in Japan prospectively evaluated the safety of 3-month DAPT after implantation of the Ultimaster bioresorbable polymer sirolimus-eluting stent (BP-SES). The secondary objective was to investigate the appropriateness of P2Y12 receptor inhibitor monotherapy compared with aspirin monotherapy after 3 months. The researchers enrolled 1,695 patients with a mean age of 70 years who were treated with U-SES and considered appropriate for 3-month DAPT after implantation.
The primary endpoint was a composite endpoint of all-cause death, myocardial infarction, stroke (ischemic and hemorrhagic), Academic Research Consortium (ARC) definite/probable stent thrombosis, and serious bleeding (Bleeding Academic Research Consortium [BARC] 3 or 5) during the 12 months after stent implantation. Major secondary endpoints included a comparison of the incidence of each event for each continued antiplatelet drug.
Of the 1,695 patients enrolled, 1,686 completed 3-month clinical follow-up while 1,616 completed 1-year clinical follow-up. Patient-level adjusted historical data from 542 subjects in the CENTURY II cohort was used as the control group. Patients in that trial received the same stent but took DAPT for 1 year.
Dr. Kozuma reported that the primary endpoint occurred in 4.3% of patients in the MODEL U-SES group, compared with 5.7% of patients in the CENTURY II BP-SES group, a difference of –3.17%, which demonstrated noninferiority of the trial (P less than .001). At 3 months, P2Y12 inhibitor monotherapy was equivalent to aspirin monotherapy in terms of both bleeding and thrombotic events (2.5% in each modality; hazard ratio, 1.14; P = 0.71).
Dr. Kozuma acknowledged certain limitations of the trial, including the fact that propensity score adjusted analysis “may not compensate the selection bias of this study sufficiently, since considerable baseline difference was observed. Also, comparison between aspirin and P2Y12 receptor inhibitors was not randomized so that the safety and efficacy of each antiplatelet monotherapy cannot be conclusive.”
Despite these limitations, he concluded that the trial “demonstrated that 3-month DAPT was noninferior to an adjusted cohort of longer DAPT after BP-SES implantation in net adverse clinical events. Direct comparison between P2Y12 inhibitor and aspirin would be necessary to confirm the efficacy and safety of P2Y12 inhibitor monotherapy in a randomized fashion.”
The meeting was sponsored by the Cardiovascular Research Foundation.
Terumo sponsored the trial. Dr. Kozuma disclosed that he serves on the scientific advisory boards for and has received honoraria from Terumo, Abbott Vascular Japan, Boston Scientific Japan, Daiichi-Sankyo, Sanofi, Bayer, Boehringer Ingelheim and Bristol-Meyers Squibb.
SOURCE: Kozuma K et al. TCT 2019, late-breaking presentation.