In short
Avalotcagene Ontaparvovec is an innovative gene therapy being studied in clinical trials for the treatment of late-onset Ornithine Transcarbamylase (OTC) deficiency. This rare genetic disorder affects the body's ability to process nitrogen, leading to potentially dangerous ammonia buildup in the blood. The clinical trials aim to evaluate the safety and effectiveness of this therapy in improving OTC function and maintaining safe ammonia levels in patients aged 12 and older.
At a glance
- Drug Name
- Avalotcagene Ontaparvovec (DTX301)
- Condition Treated
- Late-onset Ornithine Transcarbamylase (OTC) Deficiency
- Type of Therapy
- Gene therapy using adeno-associated virus serotype 8 (AAV8)
- Administration
- Single intravenous infusion
- Trial Phase
- Phase 3
- Primary Objectives
- Evaluate efficacy in maintaining safe plasma ammonia levels and achieving complete response
- Key Eligibility Criteria
- Age 12+, confirmed OTC deficiency diagnosis, history of hyperammonemia
- Study Duration
- Up to 324 weeks (about 6 years) for long-term follow-up
- Safety Monitoring
- Adverse events, laboratory values, physical examinations, vital signs
What is Avalotcagene Ontaparvovec?
Avalotcagene ontaparvovec, also known by its product codes DTX301 or SCAAV8OTC, is an innovative gene therapy designed to treat a rare genetic disorder. It is classified as an advanced therapy medicinal product, specifically a gene therapy medicinal product.
What Condition Does It Treat?
Avalotcagene ontaparvovec is being developed to treat late-onset ornithine transcarbamylase (OTC) deficiency. OTC deficiency is a rare genetic disorder that affects the urea cycle, a process in the body that removes ammonia from the blood. People with this condition can't properly process nitrogen, leading to a dangerous build-up of ammonia in the blood (hyperammonemia).
How Does It Work?
This therapy uses a recombinant adeno-associated virus serotype 8 (AAV8) vector to deliver a functional copy of the OTC gene to the patient's liver cells. The AAV8 vector is a modified virus that can't cause disease but can efficiently deliver genetic material to cells. Once inside the liver cells, this gene should enable the production of the OTC enzyme, potentially correcting the underlying cause of the disease.
Clinical Trials
Avalotcagene ontaparvovec is currently being studied in clinical trials:
- A long-term follow-up study (Phase I/II) is evaluating the safety and efficacy of a single intravenous dose in adults with late-onset OTC deficiency over a period of up to 416 weeks (8 years).
- A Phase 3 randomized, double-blind, placebo-controlled study is ongoing for patients 12 years and older with late-onset OTC deficiency.
Potential Benefits
The main goals of this treatment are to:
- Improve OTC function and maintain safe ammonia levels in the blood.
- Reduce the occurrence of hyperammonemic crises (HACs), which are dangerous episodes of high ammonia levels.
- Improve overall health outcomes for patients with OTC deficiency.
Safety Considerations
As with any new treatment, safety is a primary concern. The clinical trials are closely monitoring:
- The incidence of adverse events (AEs) and serious adverse events (SAEs).
- Changes in laboratory values, physical examination results, and vital signs.
- The development of antibodies against the OTC protein.
Who Is Eligible for This Treatment?
Based on the ongoing clinical trials, potential candidates for this treatment include:
- Patients 12 years of age or older.
- Those with a confirmed diagnosis of late-onset OTC deficiency.
- Patients with a documented history of at least one symptomatic hyperammonemia episode.
However, there are several exclusion criteria, including liver transplant recipients, those with significant liver disease, and patients with certain active infections.
Future Prospects
Avalotcagene ontaparvovec represents a promising approach to treating OTC deficiency. If successful, it could offer a one-time treatment that addresses the root cause of the disease, potentially reducing or eliminating the need for current management strategies like ammonia scavenger therapy and protein-restricted diets.
As research continues, more information will become available about the long-term safety and efficacy of this innovative gene therapy. Patients with OTC deficiency and their families should stay informed about the progress of these clinical trials and discuss potential treatment options with their healthcare providers.