Topical trichloroacetic acid versus electrocautery for treatment of anal intraepithelial neoplasia in people living with HIV: a multicentre, randomised, non-inferiority trial (TECAIN-study)

Purpose To compare efficacy and safety of topical trichloroacetic acid (TCA) versus electrocautery (ECA) for the treatment of human papillomavirus (HPV)-associated anal intraepithelial neoplasia (AIN) in people living with HIV (PLWH). Methods The TECAIN-study was a prospective, multicentre, randomised (1:1 block-randomisation), open-label, non-inferiority trial in PLWH with histologically confirmed AIN recruited from seven German proctological units. The primary endpoint (PE) was therapeutic success defined as a combination of complete clinical response evaluated by high-resolution-anoscopy and histological AIN-clearance/regression four weeks after the end-of-treatment (4-weeks-follow-up, 4WFU). Secondary endpoints were assessed at 4WFU and 24WFU. Efficacy was analysed in the intention-to-treat-population as primary analysis with a non-inferiority margin of -12%. Results Of 659 PLWH screened with HRA, 257 patients with AIN were randomised. Therapeutic outcome was assessed in 233 PLWH (TCA n = 118, ECA n = 115). The PE was reached in 62 patients of the TCA-group (52.5%) versus 71 patients of the ECA-group (61.7%) (difference in proportion − 9.2%, 95%CI -21.8% to 3.5%). While non-inferiority of TCA could not be shown for the PE at 4WFU, TCA was non-inferior to ECA at 24WFU (therapeutic success 50.8% vs. 48.7% (difference 2.2%, 95%CI -10.7% to 15.0%)). Adverse events occurred in 67.8% in both groups at 4WFU (mostly mild or moderate). Severe treatment-related pain was significantly less frequent in the TCA-group (4.2%) compared to the ECA-group (14.8%). HPV-findings did not differ between treatment groups between baseline and follow-up visits. Conclusion TCA is an effective, well-tolerated and less complex alternative to ECA for the treatment of AIN in PLWH.