Gene therapy gel holds promise for treating skin diseases

In 2016, dermatologists Jean Tang and Peter Marinkovich treated Paul Martinez for epidermolysis bullosa as part of a clinical trial using genetically modified skin grafts

In a trial led by researchers at Stanford School of Medicine, a gene therapy gel was applied to the wounds of nine patients, three of whom were children, with the vesicular skin disease epidermolysis bullosa, Help wounds heal and keep them healed for several months

This trial is the first to show that gene therapy vectors can be effective in treating skin conditions when applied topically

A 10-year-old wound covered most of the patient's body and healed 70 percent, while all other wounds healed completely after treatment

"Wounds heal quickly, but more importantly, they stay closed," said Peter Marinkovich, MD, director of the Blister Disease Clinic at Stanford School of Medicine

Marinkovich says the gel is stable at room temperature and can be used without expertise during routine bandage changes -- a key advantage for patients around the world who struggle to access professional medical care

Marinkovich, associate professor of dermatology, is the senior author of the study, which appears March 28 in the journal Nature Medicine

"The Butterfly Child"

Nine patients in the trial had recessive dystrophic epidermolysis bullosa, or RDEB for short

People with this condition are called "butterfly children" because their skin is so fragile that it blisters at the slightest touch

For more than a decade, researchers at Stanford Medicine have been developing treatments designed to deliver a complete copy of a gene called COL7A1 to patients with RDEB

In contrast, the gel used in the current study was applied topically on a weekly outpatient basis over a short period of time during regular bandage changes

Unlike many other viruses used in gene therapy, herpes simplex virus does not integrate into the host's genome when it infects cells

Prior to launching a clinical trial of nine RDEB patients, including three children, the researchers tested the treatment for RDEB in skin cells grown in a laboratory, in patients with skin transplants and in transgenic mice for the disease.

Test the gel on a patient

The researchers treated each patient's two wounds over a 25-day period, applying the gel to one wound and a placebo to the other

Most wounds treated with the gene therapy gel heal within 3 months of treatment

Skin sections from seven trial patients showed that it started making collagen VII as early as nine days after treatment began
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In at least one case, this expression persisted for nearly 100 days
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Trial participants experienced few adverse events, and those that occurred were mild
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"We found no problems with repeated use of the gel, and patients and their families were very enthusiastic about the results," Marinkovich said
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"I'm very happy that if the Food and Drug Administration approves it for clinical use, we will will be able to reach more patients with this devastating disease
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"

Phase 3 trials of the therapy have been completed
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The researchers plan to publish their findings and submit them to the U.
S.
Food and Drug Administration (FDA) for approval of the drug
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