NITYR^® is a hydroxyphenyl-pyruvate dioxygenase inhibitor indicated for the treatment of adult and pediatric patients with hereditary tyrosinemia type 1 (HT-1) in combination with dietary restriction of tyrosine and phenylalanine.

Do not take NITYR if you are allergic to nitisinone or any other ingredients. Tell your healthcare provider about any health problems, and if you are pregnant or planning to become pregnant and/or breastfeeding, before starting treatment.

If your intake of tyrosine and phenylalanine is not restricted enough, the level of tyrosine in your blood can become too high. When tyrosine levels rise above 500 micromol/L, this may cause:

• Eye problems such as corneal ulcers, cloudy patches on the cornea, irritation, redness, eye discomfort, or sensitivity to light.
• Problems with learning or delays in development.
• Painful, thickened skin on the palms of the hands or soles of the feet.

Your healthcare provider should not adjust NITYR dosage in order to lower the levels of tyrosine in the blood. Your healthcare provider will check your eyes with a slit‑lamp before you start taking NITYR, will check them regularly during treatment, and may examine your eyes again if you develop any symptoms or if your tyrosine levels go above 500 micromol/L.

• You may develop leukopenia (reduction in the number of white blood cells, which form part of the immune system) and severe thrombocytopenia (abnormally low levels of platelets, which help the blood to clot).
• Your healthcare provider will monitor platelet and white blood cell counts and will adjust your medication accordingly.

The most common side effects (seen in at least 1% of patients) in people with HT‑1 taking nitisinone include higher‑than‑normal tyrosine levels, low platelet or white blood cell counts, and eye‑related problems such as redness, cloudy areas on the cornea, inflammation, eye pain, swollen eyelids, cataracts, low granulocyte counts, and extreme sensitivity to light. Other commonly reported effects include nosebleeds, itching, skin inflammation or peeling, rashes, dry skin, and hair loss.

Less common side effects (reported in fewer than 1% of patients) include serious conditions such as death, seizures, brain tumors or brain disorders, severe restlessness, bluish‑colored skin, stomach pain, diarrhea, mouth sores or rashes on mucous membranes, bleeding in the digestive tract, black stools, increased liver enzymes, enlarged liver, low blood sugar, severe infections like sepsis, and bronchitis.

Nitisinone can interfere with the effect of other medicines. Tell your healthcare provider or pharmacist if you are taking, have recently taken, or might take any other medicines.

Pregnancy: The safety of this medicine has not been studied in pregnancy. Tell your healthcare provider immediately if you become pregnant or planning to become pregnant.
Lactation: The safety of this medicine has not been studied in breastfeeding women. Tell your healthcare provider immediately if you plan to breastfeed.
Pediatric Use: The safety and effectiveness of nitisinone has been established in pediatric patients for the treatment of HT-1 in combination with dietary restriction of tyrosine and phenylalanine. Use of NITYR in pediatric patients is supported by evidence from one open-label, uncontrolled clinical study conducted with another oral formulation of nitisinone in 207 patients with HT-1 ages 0 to 22 years (median age 9 months).
Geriatric Use: Clinical studies of nitisinone did not include any subjects aged 65 and over. No clinical studies of nitisinone have been performed in geriatric patients. Your healthcare provider will adjust the dose based on your requirements.

For more detailed information, please refer to the full Prescribing Information at https://nityr.com/pi/.

You may also report side effects directly by calling Cycle Pharmaceuticals Ltd at 1-855-831-5413, or the FDA at: 1-800-FDA-1088 or www.fda.gov/medwatch.