Thirty-six-month Prospective Study of Transvaginal Bovine Graft vs Native Tissue Repair for the Treatment of Pelvic Organ Prolapse

Objective(s): To compare the safety and effectiveness of dermal bovine transvaginal graft, Xenform, to native tissue in the surgical treatment of anterior and/or apical pelvic organ prolapse. This study was designed in conjunction with Food and Drug Administration requirements.

Methods: This was a prospective, non-randomized, parallel cohort, multi-center trial. The primary objective was to demonstrate noninferiority between transvaginal graft and native tissue repair at 36 months compared to baseline. Treatment success was based on a composite of objective and subjective measures. The co-primary outcome was the rate of serious device- or procedure-related adverse events. A total of 228 patients at 25 sites were included in the study arm and 485 patients underwent native tissue repair. Propensity score stratification was applied to achieve balance between treatment groups. Study outcomes were compared in per protocol and intent-to-treat analysis.

Results: The primary outcome, treatment success at 36 months, was 83.6% (191/228) for transvaginal graft and 80.5% (390/485) native tissue repair (0.2%, 90% confidence interval [-5.6% to 5.9%]), demonstrating noninferiority at a preset margin of -12%. The overall rate of severe adverse events was 5.3% (12/228) in transvaginal graft vs 2.7% (13/485) in native tissue repair groups. The study group demonstrated noninferiority in serious adverse events at the preset margin of 11.6% (2.0%, 90% confidence interval [-0.8% to 4.7%]). There were no reports of graft erosion, and graft exposure rates were low (0.9% [2/228]).

Conclusions: Transvaginal repair of anterior and/or apical prolapse with a biological graft is noninferior to traditional native tissue repair in effectiveness and safety at 36 months.