New Nitisinone Tablets Do Not Require Refrigeration

James Radke, PhD

For quite some time, the only orphan drug available for people with hereditary tyrosinemia type 1 (HT-1) was SOBI’s Orfadin (nitisinone).
That is changing. Last month, Cycle Pharmaceuticals announced their nitisinone tablets have been approved by Health Canada. These tablets, unlike Orfadin, can be stored at room temperature.
HT-1 is an extremely rare metabolic disease with about 1,000 people to have the disease in the world. The focus on Canada is logical given that the prevalence of HT-1 is high in Quebec with approximately 100 people affected.
In a press release, Antonio Benedetti, CEO, Cycle Pharmaceuticals said, “Nitisinone is a life-long twice-a-day treatment for HT-1 patients. Cycle has worked with physicians and patient groups to reduce the impact that this treatment has on their daily lives. It has taken us more than 4 years to develop a nitisinone tablet that meets patients’ needs, ensuring the same medical treatment. We are keen to see patients fully benefitting from the new characteristics our product brings, and are looking forward to working with patients, caregivers and physicians to continue to improve the support for the HT-1 community.”
Hopefully, the drug will be available in the United States and Europe in the near future.

Hereditary Tyrosinemia Type 1 (HT-1)

Tyrosinemia type I is caused by a deficiency of the enzyme fumarylacetoacetate hydrolase (FAH). The absence of FAH leads to an accumulation of toxic metabolic products in various body tissues, which in turn results in progressive damage to the liver and kidneys. Tyrosinemia type I affects males and females in equal numbers.

Treatment for HT-1 consists of a low phenylalanine and tyrosine diet plus nitisinone.  

Nitisinone inhibits 4-hydroxyphenylpyruvate dioxygenase so that toxic by-products of tyrosine do not accumulate in the body.

In the video clips below, Jon Miller, founder of NOTA  and George Diaz, MD of Mount Sinai Hospital talk about the condition from both a parent's and clinician's perspective.

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