In a news release from June 2, 2021, biopharmaceutical company Soleno Therapeutics, Inc. (“Soleno”) shared an exciting update. The company’s investigational treatment, DCCR (diazoxide choline) Extended-Release tablets, received Orphan Drug designation from the FDA for the treatment of patients with glycogen storage disease type 1a (GSD1A).
To begin, what are DCCR tablets? According to Soleno, DCCR stands for Diazoxide Choline Controlled Release. The biopharmaceutical company further explains that DCCR extended-release tablets are:
a novel, proprietary extended-release, crystalline salt formulation of diazoxide, which is administered once-daily. The parent molecule, diazoxide, has been used for decades in thousands of patients in a few rare diseases in neonates, infants, children and adults.
Beyond GSD1A, Soleno has been evaluating DCCR tablets as a potential treatment for patients with Prader-Willi syndrome (PWS). In fact, the tablets even received Orphan Drug status for this treatment area as well. Currently, Soleno is participating in clinical trials evaluating DCCR tablets for PWS, though no current trials have begun to evaluate DCCR tablets for GSD1A.
However, the Orphan Drug status for GSD1A is still extremely valuable. Currently, there are no FDA-approved treatments for this rare inherited disorder. Soleno hopes that DCCR tablets can regulate hypoglycemia (low blood sugar) and improve quality of life (QOL) for patients with GSD1A. Additionally, the company gained a variety of benefits from receiving Orphan Drug status, which is granted to drugs or biologics intended to treat those with rare or life-threatening diseases. A “rare” disease is defined as one affecting under 200,000 Americans. Soleno will now receive fee waivers and tax credits, FDA regulatory assistance, and 7 years of market exclusivity once DCCR tablets are approved.
Glycogen Storage Disease Type 1A (GSD1A)
G6PC gene mutations cause glycogen storage disease type 1a (GSD1A), also known as Von Gierke disease. Because these mutations are inherited in an autosomal recessive pattern, patients must receive one defective gene from each parent. Altogether, these genetic mutations cause enzyme deficiencies – in particular, glucose-6-phosphatase (G6Pase) deficiencies. Normally, this enzyme helps break down glycogen throughout the body. But when the enzyme is deficient, glycogen begins accumulating in organs and tissues, causing a variety of health issues. Often, glycogen builds up in the liver and kidneys. As a result, patients have difficulty regulating blood sugar between meals. Organ function can also be damaged.
In some cases, symptoms appear directly following birth. However, in a majority of cases, GSD1A symptoms appear once an infant begins sleeping longer through the night, typically around 3-4 months old. These symptoms include:
- Low blood sugar
- Enlarged spleen, kidney, or liver
- Low muscle tone
- Cognitive impairment
- Doll-like face with full cheeks
- Delayed puberty
- Heat intolerance
- Muscle pain or cramping
- Short stature and/or poor growth
- Easy bruising
- High blood uric acid levels
- Cognitive impairment
- Xanthomas (yellow fatty deposits under the skin)
- Thin appendages
- Impaired platelet function
- Abdominal swelling and/or distention
- High blood cholesterol levels
- Kidney disease
- Pulmonary hypertension
- Benign liver tumors
However, with diet, medication, and careful disease management, many people with GSD1A live into adulthood. Once in late adolescence or adulthood, though, patients should be aware of a higher risk of high blood pressure, cancerous liver tumors, or kidney-related complications.