PlatEleT-rich plasma and Autologous lipotransfer to treat vulval fibrosis in Lichen Sclerosus – the PETALS multicentre randomised controlled feasibility trial

Background Vulval Lichen Sclerosus (VLS) is a chronic inflammatory skin disease that affects the vulva and anogenital region (1). Its prevalence is up to 3% (2,3), with peak onset in prepubertal girls and postmenopausal women. Symptoms include itching and pain, with flat, porcelain-white lesions. Scarring and loss of vulval architecture can develop in up to 79% of cases (4).

Dyspareunia caused by fourchette fissuring and erosions and psychological impact further complicate the condition and can have a significant impact on quality of life including intimacy and physical activity.

First-line treatment includes topical corticosteroids (TCS) which are effective during the acute and maintenance phases but can be insufficient in managing scarring and structural changes. Other treatments have limited efficacy evidence.

New surgical options including autologous fat transfer (AFG) and platelet-rich plasma (PRP) have shown the potential to improve VLS symptoms and VLS-related scarring and loss of architecture but lack robust prospective clinical evidence. This study aims to evaluate the feasibility of running a definitive trial investigating these treatments in VLS.

Aims The primary feasibility outcome will be the proportion of eligible patients willing to be randomised.

We will also assess the adherence to the trial protocol, the feasibility of setting up other treatment centres across the UK, running a multicentre trial and the acceptability of the treatments to patients and clinicians.

We will collect preliminary clinical efficacy and safety data to identify the most suitable outcome measures and calculate the sample size required for an adequately powered future multicentre trial.

Methods We propose a single-blind (blinded assessors) randomised controlled feasibility study with a 1:1:1 randomisation into three treatment arms: TCS only (Standard of Care – SoC), AFG + SoC and PRP + SoC.

Patients in two surgical arms will undergo a procedure under general anaesthesia where AFG and PRP will be collected and either AFG or PRP will be injected into the vulval area. Patients will be blinded to the injection they receive. A pragmatic approach of allowing patients to continue a potent TCS which they are known to tolerate will be used.

Patients with poorly controlled disease will be reviewed by a Consultant Dermatologist. We plan to recruit up to 75 patients.

The inclusion criteria are adults (>18-years), female sex, patients with expert-diagnosed clinical and/or histological diagnosis of VLS, able to give informed consent and communicate in English, and VLS-related structural changes. Patients will be followed up over the phone during the immediate postoperative period.

Follow-up visits will take place at Royal Free Hospital at 3 and 6 months.