Injections of Botulinic Toxin in Plantar Lesions of Localized Epidermolysis Bullosa Simplex (EBTox)

Toulouse University Hospital

Status and phase: Enrolling; Phase 3; Phase 2

Conditions: Epidermolysis Bullosa Simplex

Treatments: Drug: Botulinic toxin; Drug: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT03453632

RC31/16/8917

2017-002332-16 (EudraCT Number)

Details and patient eligibility

About

The investigators hypothesize that palmar injections of botulinic toxin, via an inhibition of the sudation, would limit the occurrence of blisters in localized epidermolysis bullosa simplex (LEBS).

Full description

Epidermolysis bullosa is a group of rare genetic diseases characterized by the occurrence of blisters and erosions due to skin fragility. There are 4 different subgroups, based on the location of the skin cleavage area. The most frequent subgroup is the simplex form, consisting predominantly of the localized form (localized epidermolysis bullosa simplex: LEBS). The incidence of LEBS was estimated at between 1/318.000 and 1/35.000. The disease starts early in infancy by the occurrence of blisters and erosions located on soles, secondary to frictions during the walk. The phenomenon is worsened by heat and sudation. LEBS is due to mutations in keratin genes. Life expectancy in LEBS is normal but the quality of life is significantly impaired due to permanent skin pain and limitation of everyday activities (walking, sports). There is no effective or curative treatment. Patients must limit the frictions, protect the skin and use plasters in case of skin lesions.

Botulinic toxin has an agreement for the treatment of axillary hyperhidrosis and has been shown to be also effective on palms and soles. The efficacy of botulinic toxin in plantar lesions of LEBS has been reported in the literature (one case report and a short retrospective series of 6 patients) but there is no proper study.

Enrollment: 25 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Diagnosis of LEBS based on clinical symptoms and in some cases histological or molecular findings
• Palmar skin lesions: blisters and/or : erosions, edematous and erythematous lesions, crusts. 3 lesions per foot, as a minimum
• Similar clinical severity of skin lesions on both feet
• Patient with social security
• Written consent of the patient
• Patient able to understand the study's questionnaires

Exclusion criteria

• Patients with only one leg and a different number of toes on each foot.
• Known hypersensitivity to botulinic toxin or its excipients
• Current treatment with aminosides
• Myasthenia
• Swallowing difficulties
• Respiratory disorders
• Past medical history of dysphagia or pneumopathy of inhalation
• Known allergy or contraindications to lidocaine, prilocaine, paracetamol or nitrous oxide
• Pregnancy (positive pregnancy test (β-HCG) for women of childbearing age, performed within the 2 days prior to the study. Breastfeeding.
• Contraception during 6 months from inclusion
• Mental or physical or judicial incapacity to fill the questionnaires
• Guardianship patients
• Skin infection on the soles at the time of the inclusion
• Skin lesions located on the soles, not related to LEBS (ie. post traumatic wound, wart)
• Patient suffering from dishydrosis
• Botulinic toxin injections in the previous 6 months
• Inclusion in another study in the previous 2 months

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Triple Blind

---

25 participants in 2 patient groups, including a placebo group

Botulinic toxin

Experimental group

Description:

Injections of botulinic toxin (Dysport®, Allergan) 200 UI

Treatment:

Drug: Botulinic toxin

Placebo

Placebo Comparator group

Description:

Injections of physiological serum

Treatment:

Drug: Placebo