Herpes-simplex virus type 1 (HSV-1) used as vector for carrier for gene. Gene therapy approved by USFDA for treatment of Dystrophic epidermolysis bullosa (DEB) , The butterfly Skin Disease.
Have you heard about a disease called butterfly skin disease or dystrophic Epidermolysis Bullosa? Skin of the patients affected with this disease get ruptured at any point and the body under the skin is exposed to the environment. It appears scary and red flesh of the patient is seen, which otherwise is covered with skin.
This disease is detected at the birth at infancy and even at the early age, the patient’s life is limited due to the severity of the disease as there was no treatment available for the disease until 19TH May 2023.
On 19th May 2023. United States Food and Drugs administration approved, first of its kind gene therapy for treating this scary and life threatening disease, which will save lives of children across the world. 20 children taking birth out of 1 million are found to be affected with dystrophic epidermolysis bullosa.
What is Dystrophic epidermolysis bullosa DEB ?
Dystrophic epidermolysis bullosa, the butterfly skin disease is a genetic disorder that occurs during the birth or after few years of birth causing the defect in the gene that is responsible for formation of normal skin protein, the collagen type VII chain, that makes upper and lower epidermis layers firm and fixes over the body tissues firmly.
In absence of the collagen type VII alpha 1 chain the skin is ruptured after formation of bubbles and the underneath body layer is exposed, appearing red. This increases the risk of severe infections and loss of disfigurement of body parts and tissues. Defect in the collagen is due to the mutation occurring in the COL7A1 that is responsible for production of this collagen.
A Gene therapy drug Vyjuvek is approved by US FDA on 19th May 2023 for treatment of dystrophic epidermolysis bullosa (DEB) with mutation(s) in the collagen type VII alpha 1 chain (COL7A1) gene. Vyjuvek is developed by Biotech Company Krystal Biotech, Inc.
As shown in the pictures the skin is exposed and the healing is also slower. Due to which patient’s life is under threat of serious infections.
Virus vector herpes-simplex virus type 1 (HSV-1) used to deliver gene responsible for (DEB).
The drug Vyjuvek has used herpes-simplex virus type 1 (HSV-1) virus as carrier of the gene COL7A1, the virus used is called vector virus, and its job is to just deliver the gen COL7A1 at the point of application, the virus do not multiply so that it do not produce harmful effect of virus, rather it is useful in delivering the gene in to the human body cells.
After the application of the Gene therapy drug Vyjuvek the skin formation starts like normal skin, the ruptured skin is repaired. Before this there was no treatment available for this disease Dystrophic epidermolysis bullosa (DEB).
The drug is approved by US FDA as an orphan drug, the orphan drugs are drugs meant for treatment for the rare diseases which do not have any treatment options.
Dystrophic epidermolysis bullosa (DEB) is a genetic disorder, which develops due to mutation in the COL7A1 gene that codes for collagen type VII collagen tissue which forms a layer in between outer and middle layers of skin. In patients with defective COL7A1 gene. Collagen type VII collagen tissue is not generated and patients skin ruptures forming blisters and exposing the body tissues under skin.
The virus vector used do not multiply after it penetrate the tissue cells it delivers it’s genetic material along with the gene therapy gene. This gene becomes functional and start coding for the collagen, after production of collagen normal skin is formed and the patients get relief.
Before this there was no treatment available for this disease. It’s great milestone in medicine.
There are some precautions to be taken while handling by care givers and doctors. The preparation is in a gel form and is required to be applied over the broken wounds and skin. After which the dressing is required to be discarded as biomedical waste. After handling the hands should be washed and sanitized.