A Prolongation of a Clinical Study to Evaluate the Efficacy of an Aqueous Gel Containing 2% (w/w) of Cidofovir, Directly Applied on the Cervix Exhibiting High Grade Squamous Intraepithelial Lesions.

The infections of high grade induced by the human papilloma viruses cause precancerous lesions of the cervical epithelium. The progression of these lesions can lead to the onset of cervical cancer. To reduce the risk of cancer lesions classified as 'cervical squamous intraepithelial neoplasia 2' (CIN2) and 'cervical squamous intraepithelial neoplasia 3' (CIN3), the standard treatment is the conisation of the cervix. This surgery can lead to complications such as infertility or a risk of preterm birth, hence the need to move towards a non-surgical alternative therapy.

The colvir clinical trial was a phase-II, multi center, randomized, double blind, efficacy study of an aqueous gel containing 2% (w/w) cidofovir, administrated directly on cervix exhibiting high grade squamous intraepithelial lesion (CIN 2 and 3).

This clinical trial is a prolongation of the colvir trial, in order to

* assess the long term histological and virological evolution (24 months) of 3 g of 2% (w/w) cidofovir gel, administrated directly on cervix exhibiting high grade intraepithelial neoplasia after complete response, partial response or response failure at the end of the Colvir study. * assess the long term (24 months) rate of recurrence of histological lesions of the Colvir patients after conisation, in both placebo and treatment groups.