After publication of the article in “Nature Medicine Magazine” on the new gene therapy treatment for recessive dystrophic EB, DEBRA are delighted to bring you further information on this exciting new discovery.
What is B-VEC?
This is a non-invasive gene therapy, which is applied directly to the skin. The therapy uses an inactive virus (HSV-1) to introduce two healthy copies of the collagen 7 gene (COL7A1).
This harmless inactive virus provides the cells with the necessary information to produce healthy collagen 7 protein that works correctly. The collagen 7 forms structures to keep the epidermis and the dermis together, therefore preventing the formation of blisters and wounds.
The perfect clinical trial would be random, double blind, involve the use of placebos and include a large number of participants. Unfortunately these requirements are difficult to achieve in the case of rare diseases and many clinical trials are unable to meet with all of these. However the B-VEC clinical trial successfully achieved the majority of these requirements.
- The use of placebos: the same person had a placebo applied to a wound (a harmless product that does not contain the treatment) and in a different area the B-VEC was applied.
- Randomised: the treatments for each group and individual person, placebo or B-VEC were given randomly.
- Double blind: neither the participant nor the clinician knows which treatments are being applied.
For each of the 9 participants they chose 2 similar wounds. One was treated with the placebo and the other with B-VEC once a week. The wounds were then observed to check for any side effects. The results showed that B-VEC is safe and effective with 75% of the wounds treated, healed within 3 months. Whilst only 20% of those treated with the placebo had healed. Once the wound had healed it appeared to be resistant to blistering for 3 months after the treatment.
They have recently completed phase 3 of the clinical trials where 31 people with EB have been successfully treated.
They are now completing the OLE, Open Label extension part of the research where they apply the treatments to participants from phase 3 along with other patients and continue to observe the results and effectiveness of the treatment over a longer period of time.