Methods
The study was designed as a Phase II, single-centre, double-blind, randomised control trial. Inclusion criteria were all women were ≥ 18 years of age who presented with histologically proven uVIN on biopsy, either as primary or recurrence disease. All uVIN lesions must be measurable with at least one lesion that can be accurately measured in one dimension with longest diameter ≥ 10mm. Patients with recurrence disease were treatment free for at least 12 weeks and must be able to provide a written consent to participate in the study. Exclusion criteria were patients suspected or histological proven invasive disease; pregnant, breast feeding or were trying to conceive; know allergies to any of Veregen® or placebo components; underlying immunosuppressive disease; unable to comply with protocol; severe liver dysfunction or chronic liver disease; unable to provide written consent. This study is approved by the East Midlands - Derby Research Ethics Committee with study number 13/EM/0398. All patients provided a written consent to participate in the study.
Patients who fulfilled the recruitment criteria were randomised 1:1 into receiving Veregen® (experimental) or a placebo ointment. Veregen® ointment, 10% EGCG concentration, and placebo were manufactured and supplied by MediGene AG, Germany. Patients were to apply ointment thrice daily for 16 weeks, and the frequency of application was recorded in a diary. Follow up were scheduled at two weeks (telephone call), 4, 8, 16, 32 and 52 weeks after starting treatment. Baseline biopsy for histological diagnosis was obtained prior to treatment and at 16 and 32 weeks after treatment. Recruitment to the trial was scheduled for 24 months. The study protocol is included in the supplementary information.
The primary objective was to evaluate whether application of Veregen® could induce histological resolution of uVIN when assessed at 32 weeks following the start of treatment. Histological resolution is defined as the absence of uVIN lesion or invasive cancer. The secondary objectives were to assess: clinical resolution (as measured by ≥30% reduction in the sum of the longest diameter of all lesions when compared to baseline), treatment compliance, safety and tolerability, and quality of life using McGill pain questionnaire8 and Dermatology Life Quality Index (DLQI)9 questionnaire. The primary endpoint; best histological response observed across the 32 weeks as established by blinded pathology review; was to be analysed as per Jung’s design, an analogue of Simon’s design, for randomised phase II trials. The trial was designed to have type I and type II error rates less than or equal to 0.15. Assuming that the VIN resolution rate in the control arm would be 10%, and that an improvement to 30% would be clinically important, a required total of 28 patients were to be randomised to each arm. At least 3 more cases of histological resolution at 32 weeks on the experimental arm compared to the control arm of the trial were required in order to conclude sufficient activity.
Clinical resolution was measured according to a protocol defined evaluation criteria based on RECIST, the number of patients with clinical resolution will be reported by treatment arm and proportions will be compared using 2-sample test for equality of proportions with continuity correction. Time to clinical resolution was measured as the time from randomisation to clinical resolution, patients not having resolution were censored at the date last seen, and this will be presented in a Kaplan-Meier plot. Treatment compliance were summarised at patient level taking into account both dose reductions and interruptions. Adverse event data was collected as per Common Terminology Criteria for Adverse Events (CTCAE v4.0), summary tables were presented for this data. Quality of life questionnaire scores were presented using informative plots over time.