In short
This article discusses the ongoing clinical trial evaluating the long-term safety and effectiveness of Timrepigene Emparvovec, a gene therapy treatment for two rare eye conditions: Choroideremia (CHM) and X-Linked Retinitis Pigmentosa (XLRP). The study, known as SOLSTICE, follows up on patients who have previously received this innovative treatment in earlier trials, aiming to assess its lasting impact on vision and overall eye health.
At a glance
- Drug Name
- Timrepigene Emparvovec (BIIB111)
- Conditions Treated
- Choroideremia (CHM) and X-Linked Retinitis Pigmentosa (XLRP)
- Administration Method
- Subretinal injection
- Study Type
- Long-term follow-up safety and efficacy study
- Primary Endpoint
- Safety assessments as per protocol
- Key Secondary Endpoints
- Changes in visual acuity, visual field, and quality of life measures
- Follow-up Duration
- Up to 72 months (6 years)
- Eligibility
- Participants previously treated with AAV2-REP1 (for CHM) or AAV8-RPGR (for XLRP) in antecedent studies
What is TIMREPIGENE EMPARVOVEC?
TIMREPIGENE EMPARVOVEC, also known as BIIB111 or AAV2-REP1, is a gene therapy product designed to treat certain inherited eye disorders. It is classified as an advanced therapy medicinal product, specifically a gene therapy. This innovative treatment uses a modified virus to deliver a healthy copy of a specific gene to the cells in the eye.
Medical Conditions Treated
TIMREPIGENE EMPARVOVEC is being studied for the treatment of two rare genetic eye disorders:
- Choroideremia (CHM): A rare inherited disorder that causes progressive vision loss, primarily affecting males.
- X-Linked Retinitis Pigmentosa (XLRP): Another rare genetic condition causing vision loss, also primarily affecting males.
Both of these conditions fall under the broader category of retinitis pigmentosa, which refers to a group of inherited eye disorders affecting the retina.
How It Works
TIMREPIGENE EMPARVOVEC is designed as a gene therapy vector containing a healthy copy of the REP1 gene (Rab Escort Protein 1). Here's how it works:
- The therapy uses a modified virus called adeno-associated virus serotype 2 (AAV2) as a carrier.
- This virus is engineered to carry a healthy copy of the REP1 gene.
- When injected into the eye, it can infect both dividing and non-dividing cells in the retina.
- The healthy gene remains in the cell without integrating into the patient's DNA.
- This allows the cells to produce the normal REP1 protein, potentially slowing or stopping the progression of vision loss.
The goal of this therapy is to prevent further deterioration of vision or potentially restore some lost function in patients with CHM.
Administration
TIMREPIGENE EMPARVOVEC is administered as a subretinal injection. This means the medication is injected directly under the retina of the eye. This is a specialized procedure that must be performed by an experienced ophthalmologist.
Clinical Trial Information
A long-term follow-up study called SOLSTICE is being conducted to evaluate the safety and efficacy of TIMREPIGENE EMPARVOVEC in patients who have previously received the treatment in earlier studies. This study aims to gather data on the long-term effects of the therapy.
Eligibility Criteria
For the SOLSTICE study, participants must meet the following criteria:
- For CHM participants:
- Must be willing and able to give informed consent
- Must have participated in and completed a previous study investigating AAV2-REP1 for CHM
- For XLRP participants:
- Must be willing and able to give informed consent
- Must have received a subretinal injection of AAV8-RPGR for XLRP in a previous study
Participants may be excluded if, in the opinion of the investigator or sponsor, it is not in their best interest to participate in the study.
Safety and Efficacy Assessments
The study will assess various aspects of vision and eye health to determine the long-term safety and effectiveness of the treatment. These assessments include:
- Visual acuity: Measuring how well participants can see using standardized eye charts.
- Fundus autofluorescence: A non-invasive imaging technique to examine the health of the retina.
- Optical coherence tomography (OCT): An imaging method that provides detailed cross-sectional images of the retina.
- Microperimetry: A test to measure the sensitivity of different areas of the retina.
- Visual Function Questionnaire: A survey to assess how vision affects daily activities and quality of life.
These assessments will help researchers understand how well the treatment works over time and whether it continues to be safe for patients.