Background and Objectives: Echinacea angustifolia and purpurea have known immunomodulatory effects which boost viral clearance, including HPV infection. However, evidence regarding the improvement due to Echinacea-based supplements of cervical HPV-related pathologies is still lacking. The aim of this study is to evaluate the efficacy of Echinacea supplementation on the remission of cervical low-grade squamous intraepithelial lesions (L-SIL). Materials and Methods: A single-blind 1:1:1 parallel randomized controlled trial was conducted at the Colposcopy Unit of a tertiary care referral center. Reproductive-aged women were allocated either to (a) an oral supplement based on Echinacea extracts plus vaginal hyaluronic acid-based soft gel capsules, (b) the Echinacea supplement alone, or (c) vaginal hyaluronic acid-based soft gel capsules alone for 3 months. The primary outcome was the regression of cervical intraepithelial neoplasia (CIN)-1 for each treatment arm at 3, 6 and 12 months after the diagnosis. Secondary outcomes included changes in the epithelialization, pap smear, colposcopic parameters, histological reports, and vaginal health indexes (VHI) in the study groups. Results: 153 women (52 for arm A, 50 for arm B and 51 for arm C) completed the follow-up and were included in the analysis. There were no significant differences in both primary and secondary outcomes for the three groups after 3 months. At the 6-month follow-up, the number of persistent CIN-1 diagnoses was significantly lower in arm A (15/51), rather than in arm B (23/48, p = 0.03) and C (27/49, p = 0.03). Similarly, the same effect was seen after 12 months for treatment A (5/51) relative to B (15/48, p = 0.03) and C (14/48, p = 0.03). Colposcopic, histological and vaginal parameters were all significantly improved at 6 and 12 months for arm A relative to B and C, while no beneficial effects were seen after 3 months. Conclusions: Echinacea extracts supplementation in women with L-SIL/CIN-1 significantly boosts HPV lesion clearance, reducing the overall amount of diagnosis, histological, colposcopic and vaginal parameters after 6 and 12 months. However, a limited sample size reduces the quality of evaluated evidence, emphasizing the need for additional studies to validate these findings.
Keywords: CIN-1; Echinacea angustifolia; Echinacea purpurea; HPV; L-SIL.