The Food and Drug Administration (FDA) has approved a once daily dosing regimen for Nityr® (nitisinone; Cycle Pharmaceuticals) for the treatment of hereditary tyrosinemia type 1 (HT-1) in combination with dietary restriction of tyrosine and phenylalanine. 

The total daily dose of Nityr, a hydroxyphenyl-pyruvate dioxygenase inhibitor, may now be administered once daily in patients aged 5 years and older who have undetectable serum and urine succinylacetone concentrations after a minimum of 4 weeks on a stable dosage of nitisinone; the recommended starting dosage should still be administered twice daily.

“The inclusion of the once daily dosing option in the Nityr prescribing information provides Nityr’s patients and their prescribers with greater flexibility in dosing and titration,” said Peter Myrenfors, Chief Medical Officer, Cycle. “This new option may be more convenient to patients and their caregivers in their daily management.”

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Nityr is supplied as 2mg, 5mg, and 10mg tablets in 60-count bottles. The Company is also offering a 30-Day Free Nityr® Program for eligible patients. 

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  1. US FDA grants once daily dosing option for Nityr (nitisinone) tablets for HT-1 patients. Accessed September 15, 2020. 
  2. Nityr [package insert]. Cambridge, United Kingdom: Cycle Pharmaceuticals; 2020.