These Highlights Do Not Include All The Information Needed To Use Orfadin Safely And Effectively. See Full Prescribing Information For Orfadin.

Starting Dosage

The recommended starting dosage of ORFADIN is 0.5 mg/kg administered orally twice daily.

Principal Display Panel - 2 mg Carton Label

60 capsules NDC 66658-102-60

Orfadin^® Capsules

(Nitisinone)

2 mg

For Oral Use

sobi

Instructions for Use

ORFADIN (OR-fuh-din)

(nitisinone)

oral suspension

4 mg/mL

Read this Instructions for Use before you start taking ORFADIN oral suspension and each time you get a refill. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or your treatment.

Important information about measuring ORFADIN oral suspension:

• Use the oral syringe provided with your ORFADIN oral suspension to make sure you measure the right amount.
• You will be provided with:
  • 1 bottle of ORFADIN oral suspension
  • 1 oral syringe
  • 1 adapter (The adapter may or may not be inserted in your bottle of ORFADIN oral suspension when you receive it.)

If the adapter is not inserted in your bottle of ORFADIN oral suspension when you receive it, follow the instructions in “How to prepare a bottle of ORFADIN oral suspension if the adapter is not inserted.”

If the adapter is inserted in your bottle of ORFADIN oral suspension when you receive it, follow the instructions in “How to prepare a dose of ORFADIN oral suspension after the adapter is inserted.”

How to prepare a bottle of ORFADIN oral suspension if the adapter is not inserted:

See “How should I store ORFADIN oral suspension?” for instructions on how to store ORFADIN oral suspension if the adapter is not inserted.

• 1.
  Remove the ORFADIN oral suspension bottle from the refrigerator 30 minutes to 1 hour before using it to allow it to reach room temperature.
  
  ORFADIN oral suspension should be thrown away (discarded) 60 days after it is removed from the refrigerator and the adapter is inserted in the bottle. Write the discard date on the bottle label.

• 5.
  Follow the instructions in “How to prepare a dose of ORFADIN oral suspension after the adapter is inserted.”

How to prepare a dose of ORFADIN oral suspension after the adapter is inserted

See “How should I store ORFADIN oral suspension?” for instructions on how to store ORFADIN oral suspension after the adapter is inserted.

• 10.
  Remove the plunger from the oral syringe barrel. Rinse the oral syringe with water after each use and let it air dry. Do not replace the plunger into the barrel of the oral syringe until ready to use again for your next dose to allow it to dry. Do not throw away the oral syringe.

• Talk to your healthcare provider or pharmacist if you have questions about how to use the oral syringe or if you lose the oral syringe.

How should I store ORFADIN oral suspension?

• Store the ORFADIN oral suspension bottle in an upright position. Keep the oral syringe with your medicine.

Before the adapter is inserted into the bottle:

• If the adapter has not been inserted into the bottle, store ORFADIN oral suspension in the refrigerator between 36°F to 46°F (2°C to 8°C).
• Do not freeze ORFADIN oral suspension.

After the adapter is inserted into the bottle:

• After the adapter has been inserted into the bottle, store ORFADIN oral suspension at room temperature, 77°F (25°C) or below.
• Throw away (discard) ORFADIN oral suspension 60 days after the adapter is inserted in the bottle. You or your pharmacist should write the discard date on the bottle label.

What are the ingredients in ORFADIN oral suspension?

Active ingredient: nitisinone

Inactive ingredients: hydroxypropyl methylcellulose, glycerol, polysorbate 80, sodium benzoate, citric acid monohydrate, trisodium citrate dihydrate, strawberry aroma (artificial) and purified water

This Instructions for Use has been approved by the U.S. Food and Drug Administration.

Manufactured by:

Apotek Produktion & Laboratorier AB, Sweden

Marketed by:

Sobi, Inc

890 Winter Street

Waltham, MA 02451

© Swedish Orphan Biovitrum AB (publ). All rights reserved.

Issued: April 2016

Accidental ingestion of ORFADIN by individuals eating normal diets not restricted in tyrosine and phenylalanine will result in elevated tyrosine levels. In healthy subjects given a single 1 mg/kg dose of nitisinone, the plasma tyrosine level reached a maximum of 1200 micromol/L at 48 to 120 hours after dosing. After a washout period of 14 days, the mean value of plasma tyrosine was still 808 micromol/L. Fasted follow-up samples obtained from volunteers several weeks later showed tyrosine values back to normal. There were no reports of changes in vital signs or laboratory data of any clinical significance. One patient reported sensitivity to sunlight. Hyper-tyrosinemia has been reported with ORFADIN treatment [see Warnings and Precautions (5.1)].

ORFADIN contains nitisinone, which is a hydroxyphenyl-pyruvate dioxygenase inhibitor indicated as an adjunct to dietary restriction of tyrosine and phenylalanine in the treatment of hereditary tyrosinemia type 1 (HT-1).

Nitisinone occurs as white to yellowish-white, crystalline powder. It is practically insoluble in water, soluble in 2M sodium hydroxide and in methanol, and sparingly soluble in alcohol.

Chemically, nitisinone is 2-(2-nitro-4-trifluoromethylbenzoyl) cyclohexane-1,3-dione, and the structural formula is:

Capsules: Hard, white-opaque capsule, marked as 2 mg, 5 mg, 10 mg or 20 mg strengths of nitisinone, intended for oral administration. Each capsule contains 2 mg, 5 mg, 10 mg or 20 mg nitisinone, plus pre-gelatinized starch. The capsule shell is gelatin and titanium dioxide and the imprint is an iron oxide.

Oral suspension: 4 mg/mL, a white, slightly viscous opaque suspension. The inactive ingredients are hydroxypropyl methylcellulose, glycerol, polysorbate 80, sodium benzoate, citric acid monohydrate, trisodium citrate dihydrate, strawberry aroma (artificial) and purified water.

Glycerol: Each mL contains 500 mg.

Sodium: Each mL contains 0.7 mg (0.03 mEq).

The safety and effectiveness of ORFADIN have been established in pediatric patients for the treatment of HT-1 in combination with dietary restriction of tyrosine and phenylalanine. Use of ORFADIN in pediatric patients is supported by evidence from one open-label, uncontrolled clinical study conducted in 207 patients with HT-1 ages 0 to 22 years (median age 9 months) [see Clinical Studies (14)].

Clinical studies of nitisinone did not include any subjects aged 65 and over. No pharmacokinetic studies of nitisinone have been performed in geriatric patients. In general, dose selection for an elderly patient should be cautious reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant disease or other drug therapy in this patient population.

The efficacy and safety of ORFADIN in patients with HT-1 was evaluated in one open-label, uncontrolled study of 207 patients with HT-1, ages 0 to 22 years at enrollment (median age 9 months). Patients were diagnosed with HT-1 by the presence of succinylacetone in the urine or plasma. All patients were treated with ORFADIN at a starting dose of 0.3 to 0.5 mg/kg twice daily, and the dose was increased in some patients to 1 mg/kg twice daily based on weight, liver and kidney function tests, platelet count, serum amino acids, urinary phenolic acid, plasma and urine succinylacetone, erythrocyte PBG-synthase, and urine 5-ALA. The median duration of treatment was 22 months (range less than 1 month to 80 months). Efficacy was assessed by comparison of survival and incidence of liver transplant to historical controls.

For patients presenting with HT-1 younger than 2 months of age who were treated with dietary restriction and nitisinone, 2- and 4-year survival probabilities were 88% and 88%, respectively. Data from historical controls showed that patients presenting with HT-1 at younger than 2 months of age and treated with dietary restriction alone had 2- and 4-year survival probabilities of 29% and 29%, respectively. For patients presenting with HT-1 between 2 months and 6 months of age who were treated with dietary restriction and nitisinone, 2- and 4-year survival probabilities were 94% and 94%, respectively. Data for historical controls showed that patients presenting with HT-1 between 2 months and 6 months of age treated with dietary restriction alone had 2- and 4-year survival probabilities of 74% and 60%, respectively.

The effects of nitisinone on urine and plasma succinylacetone, porphyrin metabolism, and urinary alpha-1-microglobulin were also assessed in this clinical study.

Porphyria-like crisis were reported in 3 patients (0.3% of cases per year) during the clinical study. This compares to an incidence of 5 to 20% of cases per year expected as part of the natural history of the disorder. An assessment of porphyria-like crises was performed because these events are commonly reported in patients with HT-1 who are not treated with nitisinone.

Urinary alpha-1-microglobulin, a proposed marker of proximal tubular dysfunction, was measured in 100 patients at baseline. The overall median pretreatment level was 4.3 grams/mol creatinine. After one year of treatment in a subgroup of patients (N=100), overall median alpha-1-microglobulin decreased by 1.5 grams/mol creatinine. In patients 24 months of age and younger in whom multiple values were available (N=65), median alpha-1-microglobulin levels decreased from 5.0 to 3.0 grams/mol creatinine (reference value for age less than or equal to 12 grams/mol creatinine). In patients older than 24 months in whom multiple values were available (N=35), median alpha-1-microglobulin levels decreased from 2.8 to 2.0 grams/mol creatinine (reference for age less than or equal to 6 grams/mol creatinine).

The long term effect of nitisinone on hepatic function was not assessed.

None.

Most common adverse reactions (>1%) are elevated tyrosine levels, thrombocytopenia, leukopenia, conjunctivitis, corneal opacity, keratitis, photophobia, eye pain, blepharitis, cataracts, granulocytopenia, epistaxis, pruritus, exfoliative dermatitis, dry skin, maculopapular rash and alopecia. (6.1)

To report SUSPECTED ADVERSE REACTIONS, contact Swedish Orphan Biovitrum at 1-866-773-5274 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Nitisinone is a moderate CYP2C9 inhibitor, a weak CYP2E1 inducer and an inhibitor of OAT1/OAT3. Table 2 includes drugs with clinically important drug interactions when administered concomitantly with ORFADIN and instructions for preventing or managing them.

In a clinical study, patients with HT-1 were diagnosed by the presence of succinylacetone in urine or plasma and treated with ORFADIN [see Clinical Studies (14)]. In all 186 patients whose urine succinylacetone was measured, the urinary succinylacetone concentration decreased to less than 1 mmol/mol creatinine, the lower limit of quantitation. The median time to normalization of urine succinylacetone was 0.3 months. The probability of recurrence of abnormal values of urine succinylacetone was 1% at a nitisinone concentration of 37 micromol/L (95% confidence interval: 23, 51 micromol/L). In 87% (150/172) of patients whose plasma succinylacetone was measured, the plasma succinylacetone concentration decreased to less than 0.1 micromol/L, the lower limit of quantitation. The median time to normalization of plasma succinylacetone was 3.9 months.

In another study, comparing two dosing regimens, succinylacetone was measured in urine and/or blood in 16 patients with HT-1 aged 5 years to 24 years. All study patients were on a stable ORFADIN daily dosage (0.4 mg/kg/day to 1 mg/kg/day) during both study dosing regimens. After at least 4 weeks of twice daily dosing with ORFADIN, both the urine and/or blood succinylacetone concentrations were below the limit of quantitation for the assay. Patients were then switched to once daily dosing with the same total daily dosage of ORFADIN and blood and/or urine succinylacetone concentrations remained undetectable when measured following at least 4 weeks of treatment with once daily dosing.

Nitisinone inhibits catabolism of the amino acid tyrosine and can result in elevated plasma levels of tyrosine. Therefore, treatment with nitisinone requires restriction of the dietary intake of tyrosine and phenylalanine to prevent the toxicity associated with elevated plasma levels of tyrosine [see Warnings and Precautions (5.1)].

The single-dose pharmacokinetics of nitisinone have been studied for both ORFADIN capsules and ORFADIN oral suspension in healthy adult subjects and the multiple-dose pharmacokinetics have been studied for ORFADIN capsules in healthy subjects.

ORFADIN^® is 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.

Nitisinone is a competitive inhibitor of 4-hydroxyphenyl-pyruvate dioxygenase, an enzyme upstream of fumarylacetoacetate hydrolase (FAH) in the tyrosine catabolic pathway. By inhibiting the normal catabolism of tyrosine in patients with HT-1, nitisinone prevents the accumulation of the catabolic intermediates maleylacetoacetate and fumarylacetoacetate. In patients with HT-1, these catabolic intermediates are converted to the toxic metabolites succinylacetone and succinylacetoacetate, which are responsible for the observed liver and kidney toxicity. Succinylacetone can also inhibit the porphyrin synthesis pathway leading to the accumulation of 5-aminolevulinate, a neurotoxin responsible for the porphyric crises characteristic of HT-1.

• Elevated Plasma Tyrosine Levels, Ocular Symptoms, Developmental Delay and Hyperkeratotic Plaques: Inadequate restriction of tyrosine and phenylalanine intake can lead to elevations in plasma tyrosine, which at levels above 500 micromol/L can result in symptoms, intellectual disability and developmental delay or painful hyperkeratotic plaques on the soles and palms; do not adjust ORFADIN dosage in order to lower the plasma tyrosine concentration. Obtain slit-lamp examination prior to treatment, regularly during treatment; Reexamine patients if symptoms develop or tyrosine levels are > 500 micromol/L. Assess plasma tyrosine levels in patients with an abrupt change in neurologic status. (5.1)
• Leukopenia and Severe Thrombocytopenia: Monitor platelet and white blood cell counts. (5.2)
• Risk of Adverse Reactions Due to Glycerol Content of ORFADIN Oral Suspension: Doses of 20 mL of ORFADIN oral suspension may cause headache, upset stomach and diarrhea due to the glycerol content. Consider switching patients to ORFADIN capsules. (5.3)

Recommended Dosage (2.1):

• The recommended starting dosage is 0.5 mg/kg orally twice daily.
• In patients 5 years of age and older who have undetectable serum and urine succinylacetone concentrations after a minimum of 4 weeks on a stable dosage of nitisinone, the total daily dose may be given once daily.
• Titrate the dosage based on biochemical and/or clinical response, as described in the full prescribing information.
• The maximum total daily dosage is 2 mg/kg orally.

Preparation and Administration Instructions (2.2):

• For instructions on preparing, measuring and administering the oral suspension, see the full prescribing information.
• Maintain dietary restriction of tyrosine and phenylalanine
• Take ORFADIN capsules at least one hour before, or two hours after a meal
• For patients who have difficulties swallowing capsules and who are intolerant to the oral suspension, the capsules may be opened and the contents suspended in a small amount of water, formula or apple sauce immediately before use.

Take ORFADIN oral suspension without regard to meals.

• Capsules: 2 mg, 5 mg, 10 mg and 20 mg white capsules imprinted with “NTBC” followed by “2 mg”, “5 mg”, “10 mg” or ”20 mg”, indicating the actual amount of nitisinone in each capsule.
• Oral suspension: 4 mg/mL, a white, slightly viscous opaque suspension.

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

ORFADIN was studied in one open-label, uncontrolled study of 207 patients with HT-1, ages 0 to 22 years at enrollment (median age 9 months), who were diagnosed with HT-1 by the presence of succinylacetone in the urine or plasma. The starting dose of ORFADIN was 0.3 to 0.5 mg/kg twice daily, and the dose was increased in some patients to 1 mg/kg twice daily based on weight, biochemical, and enzyme markers. The recommended starting dosage of ORFADIN is 0.5 mg/kg twice daily [see Dosage and Administration (2.1)]. Median duration of treatment was 22 months (range 0.1 to 80 months).

The most serious adverse reactions reported during ORFADIN treatment were thrombocytopenia, leukopenia, porphyria, and ocular/visual complaints associated with elevated tyrosine levels [see Warnings and Precautions (5.1, 5.2)]. Fourteen patients experienced ocular/visual events. The duration of the symptoms varied from 5 days to 2 years. Six patients had thrombocytopenia, three of which had platelet counts 30,000/microL or lower. In 4 patients with thrombocytopenia, platelet counts gradually returned to normal (duration up to 47 days) without change in ORFADIN dose. No patients developed infections or bleeding as a result of the episodes of leukopenia and thrombocytopenia.

Patients with HT- 1 are at increased risk of developing porphyric crises, hepatic neoplasms, and liver failure requiring liver transplantation. These complications of HT-1 were observed in patients treated with nitisinone for a median of 22 months during the clinical trial (liver transplantation 13%, liver failure 7%, malignant hepatic neoplasms 5%, benign hepatic neoplasms 3%, porphyria 1%).

The most common adverse reactions reported in the clinical trial are summarized in Table 1.

Adverse reactions reported in less than 1% of the patients, included death, seizure, brain tumor, encephalopathy, hyperkinesia, cyanosis, abdominal pain, diarrhea, enanthema, gastrointestinal hemorrhage, melena, elevated hepatic enzymes, liver enlargement, hypoglycemia, septicemia, and bronchitis.

Advise the patient to read the FDA-approved patient labeling (Instructions for Use).

Capsules: White capsules marked in black with "NTBC" and identified as 2 mg, 5 mg, 10 mg or 20 mg strengths of nitisinone. The capsules are packed in a high density (HD) polyethylene container with a tamper-resistant low density (LD) polyethylene snap-on cap. Each bottle contains 60 capsules.

•  
  2 mg white capsules imprinted "NTBC 2 mg" in black ink, NDC 66658-102-60
•  
  5 mg white capsules imprinted "NTBC 5 mg" in black ink, NDC 66658-105-60
•  
  10 mg white capsules imprinted "NTBC 10 mg" in black ink, NDC 66658-110-60
•  
  20 mg white capsules imprinted "NTBC 20 mg" in black ink, NDC 66658-120-60
•  
  Store refrigerated at 2° to 8°C (36° to 46°F). Alternatively, patients/caregivers may store ORFADIN capsules at room temperature up to 25°C (77°F) for up to 45 days. If not used within 45 days, discard ORFADIN capsules.

Oral suspension: White, slightly viscous opaque suspension. 1 mL contains 4 mg of nitisinone. The suspension is provided in a 100 mL brown bottle (type III glass) with a white child resistant HDPE screw cap with sealing and tamper evidence. Each bottle contains 90 mL oral suspension.

Oral suspension 4 mg/mL, NDC 66658-204-90

•  
  Store refrigerated at 2°C to 8°C (36°F to 46°F) prior to first use. Do not freeze. Store upright.
•  
  After first opening, store the product at room temperature (up to 25°C (77°F)) for up to 60 days. If not used within 60 days, discard unused portion. The discard after date should be noted on the bottle

In clinical trials, patients treated with ORFADIN and dietary restriction developed transient leukopenia (3%), thrombocytopenia (3%), or both (1.5%) [see Adverse Reactions (6.1)]. No patients developed infections or bleeding as a result of the episodes of leukopenia and thrombocytopenia. Monitor platelet and white blood cell counts during ORFADIN therapy.

The carcinogenic potential of nitisinone was assessed in a 26-week oral (gavage) carcinogenicity study in Tg.rasH2 mice. There were no drug-related neoplastic findings in male or female Tg.rasH2 mice at doses up to 100 mg/kg/ day nitisinone (approximately 8.1 times the recommended initial dose of 1 mg/kg/day on a body surface area basis).

Nitisinone was not genotoxic in the Ames test and the in vivo mouse liver unscheduled DNA synthesis (UDS) test. Nitisinone was mutagenic in the mouse lymphoma cell (L5178Y/TK^+/-) forward mutation test and in an in vivo mouse bone marrow micronucleus test.

In a single dose-group study in rats given 100 mg/kg (16.2 times the recommended initial dose of 1 mg/kg/day on a body surface area basis), reduced litter size, decreased pup weight at birth, and decreased survival of pups after birth was demonstrated.

Oral doses of glycerol of 10 grams or more have been reported to cause headache, upset stomach and diarrhea. ORFADIN oral suspension contains 500 mg/mL of glycerol. Patients receiving more than 20 mL of ORFADIN oral suspension (10 grams glycerol) as a single dose are at increased risk of these adverse reactions. Consider switching patients who are unable to tolerate the oral suspension to ORFADIN capsules.

Nitisinone is an inhibitor of 4-hydroxyphenyl-pyruvate dioxygenase, an enzyme in the tyrosine metabolic pathway [see Clinical Pharmacology (12.1)]. Therefore, treatment with ORFADIN may cause an increase in plasma tyrosine levels in patients with HT-1. Maintain concomitant reduction in dietary tyrosine and phenylalanine while on ORFADIN treatment. Do not adjust ORFADIN dosage in order to lower the plasma tyrosine concentration. Maintain plasma tyrosine levels below 500 micromol/L. Inadequate restriction of tyrosine and phenylalanine intake can lead to elevations in plasma tyrosine levels and levels greater than 500 micromol/L may lead to the following:

• Ocular signs and symptoms including corneal ulcers, corneal opacities, keratitis, conjunctivitis, eye pain, and photophobia have been reported in patients treated with ORFADIN [see Adverse Reactions (6.1)]. In a clinical study in a non HT-1 population without dietary restriction and reported tyrosine levels >500 micromol/L both symptomatic and asymptomatic keratopathies have been observed. Therefore, perform a baseline ophthalmologic examination including slit-lamp examination prior to initiating ORFADIN treatment and regularly thereafter. Patients who develop photophobia, eye pain, or signs of inflammation such as redness, swelling, or burning of the eyes or tyrosine levels are > 500 micromol/L during treatment with ORFADIN should undergo slit-lamp reexamination and immediate measurement of the plasma tyrosine concentration.
• Variable degrees of intellectual disability and developmental delay. In patients treated with ORFADIN who exhibit an abrupt change in neurologic status, perform a clinical laboratory assessment including plasma tyrosine levels.
• Painful hyperkeratotic plaques on the soles and palms

In patients with HT-1 treated with dietary restrictions and ORFADIN who develop elevated plasma tyrosine levels, assess dietary tyrosine and phenylalanine intake.

Starting Dosage

The recommended starting dosage of ORFADIN is 0.5 mg/kg administered orally twice daily.

Principal Display Panel - 2 mg Carton Label

60 capsules NDC 66658-102-60

Orfadin^® Capsules

(Nitisinone)

2 mg

For Oral Use

sobi

Instructions for Use

ORFADIN (OR-fuh-din)

(nitisinone)

oral suspension

4 mg/mL

Read this Instructions for Use before you start taking ORFADIN oral suspension and each time you get a refill. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or your treatment.

Important information about measuring ORFADIN oral suspension:

• Use the oral syringe provided with your ORFADIN oral suspension to make sure you measure the right amount.
• You will be provided with:
  • 1 bottle of ORFADIN oral suspension
  • 1 oral syringe
  • 1 adapter (The adapter may or may not be inserted in your bottle of ORFADIN oral suspension when you receive it.)

If the adapter is not inserted in your bottle of ORFADIN oral suspension when you receive it, follow the instructions in “How to prepare a bottle of ORFADIN oral suspension if the adapter is not inserted.”

If the adapter is inserted in your bottle of ORFADIN oral suspension when you receive it, follow the instructions in “How to prepare a dose of ORFADIN oral suspension after the adapter is inserted.”

How to prepare a bottle of ORFADIN oral suspension if the adapter is not inserted:

See “How should I store ORFADIN oral suspension?” for instructions on how to store ORFADIN oral suspension if the adapter is not inserted.

• 1.
  Remove the ORFADIN oral suspension bottle from the refrigerator 30 minutes to 1 hour before using it to allow it to reach room temperature.
  
  ORFADIN oral suspension should be thrown away (discarded) 60 days after it is removed from the refrigerator and the adapter is inserted in the bottle. Write the discard date on the bottle label.

• 5.
  Follow the instructions in “How to prepare a dose of ORFADIN oral suspension after the adapter is inserted.”

How to prepare a dose of ORFADIN oral suspension after the adapter is inserted

See “How should I store ORFADIN oral suspension?” for instructions on how to store ORFADIN oral suspension after the adapter is inserted.

• 10.
  Remove the plunger from the oral syringe barrel. Rinse the oral syringe with water after each use and let it air dry. Do not replace the plunger into the barrel of the oral syringe until ready to use again for your next dose to allow it to dry. Do not throw away the oral syringe.

• Talk to your healthcare provider or pharmacist if you have questions about how to use the oral syringe or if you lose the oral syringe.

How should I store ORFADIN oral suspension?

• Store the ORFADIN oral suspension bottle in an upright position. Keep the oral syringe with your medicine.

Before the adapter is inserted into the bottle:

• If the adapter has not been inserted into the bottle, store ORFADIN oral suspension in the refrigerator between 36°F to 46°F (2°C to 8°C).
• Do not freeze ORFADIN oral suspension.

After the adapter is inserted into the bottle:

• After the adapter has been inserted into the bottle, store ORFADIN oral suspension at room temperature, 77°F (25°C) or below.
• Throw away (discard) ORFADIN oral suspension 60 days after the adapter is inserted in the bottle. You or your pharmacist should write the discard date on the bottle label.

What are the ingredients in ORFADIN oral suspension?

Active ingredient: nitisinone

Inactive ingredients: hydroxypropyl methylcellulose, glycerol, polysorbate 80, sodium benzoate, citric acid monohydrate, trisodium citrate dihydrate, strawberry aroma (artificial) and purified water

This Instructions for Use has been approved by the U.S. Food and Drug Administration.

Manufactured by:

Apotek Produktion & Laboratorier AB, Sweden

Marketed by:

Sobi, Inc

890 Winter Street

Waltham, MA 02451

© Swedish Orphan Biovitrum AB (publ). All rights reserved.

Issued: April 2016

Accidental ingestion of ORFADIN by individuals eating normal diets not restricted in tyrosine and phenylalanine will result in elevated tyrosine levels. In healthy subjects given a single 1 mg/kg dose of nitisinone, the plasma tyrosine level reached a maximum of 1200 micromol/L at 48 to 120 hours after dosing. After a washout period of 14 days, the mean value of plasma tyrosine was still 808 micromol/L. Fasted follow-up samples obtained from volunteers several weeks later showed tyrosine values back to normal. There were no reports of changes in vital signs or laboratory data of any clinical significance. One patient reported sensitivity to sunlight. Hyper-tyrosinemia has been reported with ORFADIN treatment [see Warnings and Precautions (5.1)].

ORFADIN contains nitisinone, which is a hydroxyphenyl-pyruvate dioxygenase inhibitor indicated as an adjunct to dietary restriction of tyrosine and phenylalanine in the treatment of hereditary tyrosinemia type 1 (HT-1).

Nitisinone occurs as white to yellowish-white, crystalline powder. It is practically insoluble in water, soluble in 2M sodium hydroxide and in methanol, and sparingly soluble in alcohol.

Chemically, nitisinone is 2-(2-nitro-4-trifluoromethylbenzoyl) cyclohexane-1,3-dione, and the structural formula is:

Capsules: Hard, white-opaque capsule, marked as 2 mg, 5 mg, 10 mg or 20 mg strengths of nitisinone, intended for oral administration. Each capsule contains 2 mg, 5 mg, 10 mg or 20 mg nitisinone, plus pre-gelatinized starch. The capsule shell is gelatin and titanium dioxide and the imprint is an iron oxide.

Oral suspension: 4 mg/mL, a white, slightly viscous opaque suspension. The inactive ingredients are hydroxypropyl methylcellulose, glycerol, polysorbate 80, sodium benzoate, citric acid monohydrate, trisodium citrate dihydrate, strawberry aroma (artificial) and purified water.

Glycerol: Each mL contains 500 mg.

Sodium: Each mL contains 0.7 mg (0.03 mEq).

The safety and effectiveness of ORFADIN have been established in pediatric patients for the treatment of HT-1 in combination with dietary restriction of tyrosine and phenylalanine. Use of ORFADIN in pediatric patients is supported by evidence from one open-label, uncontrolled clinical study conducted in 207 patients with HT-1 ages 0 to 22 years (median age 9 months) [see Clinical Studies (14)].

Clinical studies of nitisinone did not include any subjects aged 65 and over. No pharmacokinetic studies of nitisinone have been performed in geriatric patients. In general, dose selection for an elderly patient should be cautious reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant disease or other drug therapy in this patient population.

The efficacy and safety of ORFADIN in patients with HT-1 was evaluated in one open-label, uncontrolled study of 207 patients with HT-1, ages 0 to 22 years at enrollment (median age 9 months). Patients were diagnosed with HT-1 by the presence of succinylacetone in the urine or plasma. All patients were treated with ORFADIN at a starting dose of 0.3 to 0.5 mg/kg twice daily, and the dose was increased in some patients to 1 mg/kg twice daily based on weight, liver and kidney function tests, platelet count, serum amino acids, urinary phenolic acid, plasma and urine succinylacetone, erythrocyte PBG-synthase, and urine 5-ALA. The median duration of treatment was 22 months (range less than 1 month to 80 months). Efficacy was assessed by comparison of survival and incidence of liver transplant to historical controls.

For patients presenting with HT-1 younger than 2 months of age who were treated with dietary restriction and nitisinone, 2- and 4-year survival probabilities were 88% and 88%, respectively. Data from historical controls showed that patients presenting with HT-1 at younger than 2 months of age and treated with dietary restriction alone had 2- and 4-year survival probabilities of 29% and 29%, respectively. For patients presenting with HT-1 between 2 months and 6 months of age who were treated with dietary restriction and nitisinone, 2- and 4-year survival probabilities were 94% and 94%, respectively. Data for historical controls showed that patients presenting with HT-1 between 2 months and 6 months of age treated with dietary restriction alone had 2- and 4-year survival probabilities of 74% and 60%, respectively.

The effects of nitisinone on urine and plasma succinylacetone, porphyrin metabolism, and urinary alpha-1-microglobulin were also assessed in this clinical study.

Porphyria-like crisis were reported in 3 patients (0.3% of cases per year) during the clinical study. This compares to an incidence of 5 to 20% of cases per year expected as part of the natural history of the disorder. An assessment of porphyria-like crises was performed because these events are commonly reported in patients with HT-1 who are not treated with nitisinone.

Urinary alpha-1-microglobulin, a proposed marker of proximal tubular dysfunction, was measured in 100 patients at baseline. The overall median pretreatment level was 4.3 grams/mol creatinine. After one year of treatment in a subgroup of patients (N=100), overall median alpha-1-microglobulin decreased by 1.5 grams/mol creatinine. In patients 24 months of age and younger in whom multiple values were available (N=65), median alpha-1-microglobulin levels decreased from 5.0 to 3.0 grams/mol creatinine (reference value for age less than or equal to 12 grams/mol creatinine). In patients older than 24 months in whom multiple values were available (N=35), median alpha-1-microglobulin levels decreased from 2.8 to 2.0 grams/mol creatinine (reference for age less than or equal to 6 grams/mol creatinine).

The long term effect of nitisinone on hepatic function was not assessed.

None.

Most common adverse reactions (>1%) are elevated tyrosine levels, thrombocytopenia, leukopenia, conjunctivitis, corneal opacity, keratitis, photophobia, eye pain, blepharitis, cataracts, granulocytopenia, epistaxis, pruritus, exfoliative dermatitis, dry skin, maculopapular rash and alopecia. (6.1)

To report SUSPECTED ADVERSE REACTIONS, contact Swedish Orphan Biovitrum at 1-866-773-5274 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Nitisinone is a moderate CYP2C9 inhibitor, a weak CYP2E1 inducer and an inhibitor of OAT1/OAT3. Table 2 includes drugs with clinically important drug interactions when administered concomitantly with ORFADIN and instructions for preventing or managing them.

In a clinical study, patients with HT-1 were diagnosed by the presence of succinylacetone in urine or plasma and treated with ORFADIN [see Clinical Studies (14)]. In all 186 patients whose urine succinylacetone was measured, the urinary succinylacetone concentration decreased to less than 1 mmol/mol creatinine, the lower limit of quantitation. The median time to normalization of urine succinylacetone was 0.3 months. The probability of recurrence of abnormal values of urine succinylacetone was 1% at a nitisinone concentration of 37 micromol/L (95% confidence interval: 23, 51 micromol/L). In 87% (150/172) of patients whose plasma succinylacetone was measured, the plasma succinylacetone concentration decreased to less than 0.1 micromol/L, the lower limit of quantitation. The median time to normalization of plasma succinylacetone was 3.9 months.

In another study, comparing two dosing regimens, succinylacetone was measured in urine and/or blood in 16 patients with HT-1 aged 5 years to 24 years. All study patients were on a stable ORFADIN daily dosage (0.4 mg/kg/day to 1 mg/kg/day) during both study dosing regimens. After at least 4 weeks of twice daily dosing with ORFADIN, both the urine and/or blood succinylacetone concentrations were below the limit of quantitation for the assay. Patients were then switched to once daily dosing with the same total daily dosage of ORFADIN and blood and/or urine succinylacetone concentrations remained undetectable when measured following at least 4 weeks of treatment with once daily dosing.

Nitisinone inhibits catabolism of the amino acid tyrosine and can result in elevated plasma levels of tyrosine. Therefore, treatment with nitisinone requires restriction of the dietary intake of tyrosine and phenylalanine to prevent the toxicity associated with elevated plasma levels of tyrosine [see Warnings and Precautions (5.1)].

The single-dose pharmacokinetics of nitisinone have been studied for both ORFADIN capsules and ORFADIN oral suspension in healthy adult subjects and the multiple-dose pharmacokinetics have been studied for ORFADIN capsules in healthy subjects.

ORFADIN^® is 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.

Nitisinone is a competitive inhibitor of 4-hydroxyphenyl-pyruvate dioxygenase, an enzyme upstream of fumarylacetoacetate hydrolase (FAH) in the tyrosine catabolic pathway. By inhibiting the normal catabolism of tyrosine in patients with HT-1, nitisinone prevents the accumulation of the catabolic intermediates maleylacetoacetate and fumarylacetoacetate. In patients with HT-1, these catabolic intermediates are converted to the toxic metabolites succinylacetone and succinylacetoacetate, which are responsible for the observed liver and kidney toxicity. Succinylacetone can also inhibit the porphyrin synthesis pathway leading to the accumulation of 5-aminolevulinate, a neurotoxin responsible for the porphyric crises characteristic of HT-1.

• Elevated Plasma Tyrosine Levels, Ocular Symptoms, Developmental Delay and Hyperkeratotic Plaques: Inadequate restriction of tyrosine and phenylalanine intake can lead to elevations in plasma tyrosine, which at levels above 500 micromol/L can result in symptoms, intellectual disability and developmental delay or painful hyperkeratotic plaques on the soles and palms; do not adjust ORFADIN dosage in order to lower the plasma tyrosine concentration. Obtain slit-lamp examination prior to treatment, regularly during treatment; Reexamine patients if symptoms develop or tyrosine levels are > 500 micromol/L. Assess plasma tyrosine levels in patients with an abrupt change in neurologic status. (5.1)
• Leukopenia and Severe Thrombocytopenia: Monitor platelet and white blood cell counts. (5.2)
• Risk of Adverse Reactions Due to Glycerol Content of ORFADIN Oral Suspension: Doses of 20 mL of ORFADIN oral suspension may cause headache, upset stomach and diarrhea due to the glycerol content. Consider switching patients to ORFADIN capsules. (5.3)

Recommended Dosage (2.1):

• The recommended starting dosage is 0.5 mg/kg orally twice daily.
• In patients 5 years of age and older who have undetectable serum and urine succinylacetone concentrations after a minimum of 4 weeks on a stable dosage of nitisinone, the total daily dose may be given once daily.
• Titrate the dosage based on biochemical and/or clinical response, as described in the full prescribing information.
• The maximum total daily dosage is 2 mg/kg orally.

Preparation and Administration Instructions (2.2):

• For instructions on preparing, measuring and administering the oral suspension, see the full prescribing information.
• Maintain dietary restriction of tyrosine and phenylalanine
• Take ORFADIN capsules at least one hour before, or two hours after a meal
• For patients who have difficulties swallowing capsules and who are intolerant to the oral suspension, the capsules may be opened and the contents suspended in a small amount of water, formula or apple sauce immediately before use.

Take ORFADIN oral suspension without regard to meals.

• Capsules: 2 mg, 5 mg, 10 mg and 20 mg white capsules imprinted with “NTBC” followed by “2 mg”, “5 mg”, “10 mg” or ”20 mg”, indicating the actual amount of nitisinone in each capsule.
• Oral suspension: 4 mg/mL, a white, slightly viscous opaque suspension.

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

ORFADIN was studied in one open-label, uncontrolled study of 207 patients with HT-1, ages 0 to 22 years at enrollment (median age 9 months), who were diagnosed with HT-1 by the presence of succinylacetone in the urine or plasma. The starting dose of ORFADIN was 0.3 to 0.5 mg/kg twice daily, and the dose was increased in some patients to 1 mg/kg twice daily based on weight, biochemical, and enzyme markers. The recommended starting dosage of ORFADIN is 0.5 mg/kg twice daily [see Dosage and Administration (2.1)]. Median duration of treatment was 22 months (range 0.1 to 80 months).

The most serious adverse reactions reported during ORFADIN treatment were thrombocytopenia, leukopenia, porphyria, and ocular/visual complaints associated with elevated tyrosine levels [see Warnings and Precautions (5.1, 5.2)]. Fourteen patients experienced ocular/visual events. The duration of the symptoms varied from 5 days to 2 years. Six patients had thrombocytopenia, three of which had platelet counts 30,000/microL or lower. In 4 patients with thrombocytopenia, platelet counts gradually returned to normal (duration up to 47 days) without change in ORFADIN dose. No patients developed infections or bleeding as a result of the episodes of leukopenia and thrombocytopenia.

Patients with HT- 1 are at increased risk of developing porphyric crises, hepatic neoplasms, and liver failure requiring liver transplantation. These complications of HT-1 were observed in patients treated with nitisinone for a median of 22 months during the clinical trial (liver transplantation 13%, liver failure 7%, malignant hepatic neoplasms 5%, benign hepatic neoplasms 3%, porphyria 1%).

The most common adverse reactions reported in the clinical trial are summarized in Table 1.

Adverse reactions reported in less than 1% of the patients, included death, seizure, brain tumor, encephalopathy, hyperkinesia, cyanosis, abdominal pain, diarrhea, enanthema, gastrointestinal hemorrhage, melena, elevated hepatic enzymes, liver enlargement, hypoglycemia, septicemia, and bronchitis.

Advise the patient to read the FDA-approved patient labeling (Instructions for Use).

Capsules: White capsules marked in black with "NTBC" and identified as 2 mg, 5 mg, 10 mg or 20 mg strengths of nitisinone. The capsules are packed in a high density (HD) polyethylene container with a tamper-resistant low density (LD) polyethylene snap-on cap. Each bottle contains 60 capsules.

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  2 mg white capsules imprinted "NTBC 2 mg" in black ink, NDC 66658-102-60
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  5 mg white capsules imprinted "NTBC 5 mg" in black ink, NDC 66658-105-60
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  10 mg white capsules imprinted "NTBC 10 mg" in black ink, NDC 66658-110-60
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  20 mg white capsules imprinted "NTBC 20 mg" in black ink, NDC 66658-120-60
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  Store refrigerated at 2° to 8°C (36° to 46°F). Alternatively, patients/caregivers may store ORFADIN capsules at room temperature up to 25°C (77°F) for up to 45 days. If not used within 45 days, discard ORFADIN capsules.

Oral suspension: White, slightly viscous opaque suspension. 1 mL contains 4 mg of nitisinone. The suspension is provided in a 100 mL brown bottle (type III glass) with a white child resistant HDPE screw cap with sealing and tamper evidence. Each bottle contains 90 mL oral suspension.

Oral suspension 4 mg/mL, NDC 66658-204-90

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  Store refrigerated at 2°C to 8°C (36°F to 46°F) prior to first use. Do not freeze. Store upright.
•  
  After first opening, store the product at room temperature (up to 25°C (77°F)) for up to 60 days. If not used within 60 days, discard unused portion. The discard after date should be noted on the bottle

In clinical trials, patients treated with ORFADIN and dietary restriction developed transient leukopenia (3%), thrombocytopenia (3%), or both (1.5%) [see Adverse Reactions (6.1)]. No patients developed infections or bleeding as a result of the episodes of leukopenia and thrombocytopenia. Monitor platelet and white blood cell counts during ORFADIN therapy.

The carcinogenic potential of nitisinone was assessed in a 26-week oral (gavage) carcinogenicity study in Tg.rasH2 mice. There were no drug-related neoplastic findings in male or female Tg.rasH2 mice at doses up to 100 mg/kg/ day nitisinone (approximately 8.1 times the recommended initial dose of 1 mg/kg/day on a body surface area basis).

Nitisinone was not genotoxic in the Ames test and the in vivo mouse liver unscheduled DNA synthesis (UDS) test. Nitisinone was mutagenic in the mouse lymphoma cell (L5178Y/TK^+/-) forward mutation test and in an in vivo mouse bone marrow micronucleus test.

In a single dose-group study in rats given 100 mg/kg (16.2 times the recommended initial dose of 1 mg/kg/day on a body surface area basis), reduced litter size, decreased pup weight at birth, and decreased survival of pups after birth was demonstrated.

Oral doses of glycerol of 10 grams or more have been reported to cause headache, upset stomach and diarrhea. ORFADIN oral suspension contains 500 mg/mL of glycerol. Patients receiving more than 20 mL of ORFADIN oral suspension (10 grams glycerol) as a single dose are at increased risk of these adverse reactions. Consider switching patients who are unable to tolerate the oral suspension to ORFADIN capsules.

Nitisinone is an inhibitor of 4-hydroxyphenyl-pyruvate dioxygenase, an enzyme in the tyrosine metabolic pathway [see Clinical Pharmacology (12.1)]. Therefore, treatment with ORFADIN may cause an increase in plasma tyrosine levels in patients with HT-1. Maintain concomitant reduction in dietary tyrosine and phenylalanine while on ORFADIN treatment. Do not adjust ORFADIN dosage in order to lower the plasma tyrosine concentration. Maintain plasma tyrosine levels below 500 micromol/L. Inadequate restriction of tyrosine and phenylalanine intake can lead to elevations in plasma tyrosine levels and levels greater than 500 micromol/L may lead to the following:

• Ocular signs and symptoms including corneal ulcers, corneal opacities, keratitis, conjunctivitis, eye pain, and photophobia have been reported in patients treated with ORFADIN [see Adverse Reactions (6.1)]. In a clinical study in a non HT-1 population without dietary restriction and reported tyrosine levels >500 micromol/L both symptomatic and asymptomatic keratopathies have been observed. Therefore, perform a baseline ophthalmologic examination including slit-lamp examination prior to initiating ORFADIN treatment and regularly thereafter. Patients who develop photophobia, eye pain, or signs of inflammation such as redness, swelling, or burning of the eyes or tyrosine levels are > 500 micromol/L during treatment with ORFADIN should undergo slit-lamp reexamination and immediate measurement of the plasma tyrosine concentration.
• Variable degrees of intellectual disability and developmental delay. In patients treated with ORFADIN who exhibit an abrupt change in neurologic status, perform a clinical laboratory assessment including plasma tyrosine levels.
• Painful hyperkeratotic plaques on the soles and palms

In patients with HT-1 treated with dietary restrictions and ORFADIN who develop elevated plasma tyrosine levels, assess dietary tyrosine and phenylalanine intake.