In a late September 2022 news release from AVROBIO, Inc., the company’s gene therapy candidate AVR-RD-04 recently earned Rare Pediatric Disease designation. This investigational therapy is being developed as a potential treatment for those with cystinosis. Rare Pediatric Disease designation is not the first designation granted to this therapy. In fact, AVR-RD-04 has also earned Orphan Drug designation in both the United States and European Union.
An May 2022 post from the Cystinosis Research Network explains that AVR-RD-04 is:
a lentiviral-based gene therapy designed to potentially stop the progression of cystinosis with a single dose of the patient’s own hematopoietic stem cells. The stem cells are modified so they can produce functional cystinosin with the aim of substantially reducing levels of cystine in cells throughout the body.
Data from an ongoing Phase 1/2 study found AVR-RD-04 to be safe and well-tolerated. While some patients did experience side effects, these were said to be mild-to-moderate in nature.
Now, the therapy received Rare Pediatric Disease designation. This status is designed for therapies intending to treat or prevent serious or life-threatening rare conditions (affecting fewer than 200,000 Americans) in people aged 18 years or younger. One incentive that comes along with this status is a Priority Review voucher. Learn more about Rare Pediatric Disease designation.
What is Cystinosis?
Cystinosis is a multi-system inherited disorder that causes the abnormal accumulation and crystallization of cystine (an amino acid) in cells. As this cystine accumulates in cells, tissues, and organs, it can cause organ damage and other issues. Without treatment, cystinosis can be fatal. An estimated 90% of those with cystinosis, even after treatment, require kidney transplantations at some point.
Cystinosis can be considered nephropathic (severe and diagnosed in late infancy); intermediate (moderate-to-severe and developing later in life); or non-nephropathic/ocular (characterized by corneal crystals). The Cystinosis Research Network hypothesizes that around 2,000 people worldwide are living with cystinosis. Symptoms differ based on subtypes. These symptoms can (but do not always) include:
- Excessive thirst
- Corneal crystals
- Difficulty swallowing
- Muscle wasting
- Nutrient loss through urine
- Kidney damage and failure