Botulinumtoxin A Treatment in Epidermolysis Bullosa Simplex and Pachyonychia Congenita

Botulinumtoxin A Treatment in Epidermolysis Bullosa Simplex and Pachyonychia Congenita - a Double-blind Placebo-controlled Phase II Proof of Concept Study

This study evaluates the clinical effect of foot injection of the bacteria protein Botulinum toxin A on plantar pain in patients with EBS (epidermolysis bullosa simplex) or PC (pachyonychia congenita).

Epidermolysis bullosa simplex (EBS) is the most common subtype of epidermolysis bullosa and mutations in keratin genes (KRT 5/14) are responsible for this condition. Painful blisters and keratoderma of the feet are common and the blisters in EBS typically get worse in the summer due to sweating and increased environmental heat. Since 2010, also the related condition pachyonychia congenita (PC) is included in the study. The primary objective of the study is to evaluate the clinical effect of Botulinum toxin A (Dysport®), injected in the foot, on plantar pain in patients with EBS or PC. Quality of life, pain in feet, effect duration, plantar sweating and safety of the treatment will also be studied.

Inclusion Criteria:

• Informed consent received from patient
• Informed consent received from patient´s parents (when patient < 18 years)
• A solid EBS-diagnosis based on genetic analysis and/or phenotype. The EBS-diagnosis will be performed by Professor Anders Vahlquist, Swedish Centre of Genetic skin disorders, Uppsala.
• Age > 16 years
• Patients must be previously untreated with Btx A
• If female, patient is post-menopausal, surgically sterilized, or willing to use an acceptable method of birth control

Exclusion Criteria:

• Contraindication to Btx A
• Contraindication to general anaesthesia
• Use of aminoglycosides, tetracyclines , spectinomycin, lincomycin, polymyxin or muscle relaxants
• Pregnancy or lactation
• Patients unwilling to meet the requirements of the protocol
• Other medical or social reasons for exclusion at the discretion of the Investigator