RATIONALE:
Herlitz junctional epidermolysis bullosa (H-JEB), an incurable and fatal inherited skin
disease, is caused by loss-of-function mutations in LAMA3, LAMB3 and LAMC2. These mutations
result in diminished laminin 332 and epidermal-dermal adherence. 85% of JEB patients have
nonsense mutations in LAMA3, LAMB3, or LAMC2, suggesting that H-JEB is a prime therapeutic
target for nonsense suppression therapy. The investigators recently demonstrated in three
patients that topical gentamicin created new and stable laminin 332 at the dermal-epidermal
junction (DEJ), and also improved wound closure and skin quality. Furthermore, these
preliminary studies showed that intravenous gentamicin also induced laminin 332 and
transiently improved patients' clinical outcomes. No untoward side effects occurred. The
investigators propose to optimize the intravenous gentamicin regimen including dosage and
infusion schedules to enhance the therapeutic outcome.
INTERVENTION:
There will be two study designs on JEB patients with nonsense mutation(s):
A. Short Term Daily IV Gentamicin Study: Three patients of any age with JEB caused by
nonsense mutation(s) in the LAMA3 and LAMB3 genes will receive intravenous gentamicin (10
mgs/kg) daily for 24 days and then stop. Prior to treatment and at 1 month and 3 months post
treatment, selected skin test sites will have skin biopsies and the specimens evaluated for
the expression of laminin 332 at the dermal-epidermal junction by direct immunofluorescent
staining of the skin. Safety parameters such as physical exam, review of systems, laboratory
tests, audiometry, and renal function at the same time periods.
B. Long Term Biweekly IV Gentamicin Study: Three patients of any age with JEB caused by
nonsense mutation(s) in the LAMA3 and LAMB3 genes will receive intravenous gentamicin (10
mgs/kg) twice weekly for 3 months (24 total infusions) and then stop. Before and after
evaluations will be performed and will be the same as those in the short term intravenous
study outlined above.
STUDY POPULATION:
3 adults/children for who have JEB due to nonsense mutations in the LAMA3 or LAMB3 gene for
each intervention arm.
STUDY ENDPOINTS OR OUTCOMES Analysis of safety parameters, wound healing, and generation of
new laminin 332 at the dermal-epidermal junction of the skin by direct immunofluorescent
stain.
FOLLOW-UP Participants will be followed out to 90 days post treatment
STATISTICS Without treatment, these JEB patients have little or no laminin A3/laminin
B3/laminin 332 at their dermal-epidermal junction. The expression of any newly generated
laminin 332 will be measure against normal human skin (100%) by NIH Image J software.
PLANS FOR ANALYSIS Safety parameters are outlined above and will be examined at baseline and
after each patient visit. Efficacy parameters outlined above will be measured at baseline and
at post treatment days 30 and 90.