2015年6月30，口服悬液配方Orfadin（nitisinone，尼替西农）获欧盟批准，用于遗传性酪氨酸血症I型（Hereditary Tyrosinaemia type-1，HT-1）患者的治疗。HT-1是一种罕见的常染色体隐性遗传病，是由酪氨酸代谢障碍所致的一种遗传代谢病，多数患儿为急性型，起病于新生儿或婴儿期，主要累及肝脏和肾脏，若不治疗会导致肝、肾衰竭甚至死亡。
胶囊配方Orfadin于2005年上市，目前已获欧盟及全球多个国家批准，联合酪氨酸和苯丙氨酸饮食限制，用于确诊为HT-1的患者。Orfadin结合饮食限制及广泛的新生儿筛查，能够使婴幼儿及早确诊治疗，从而显著改善患者的临床结果。而在Orfadin上市前，出生2个月内确诊为HT-1的婴儿，仅有三分之一能够存活到2岁。目前全球大约有1000例HT-1患者。
Orfadin口服悬液是一种婴幼儿友好的配方，可方便准确给药剂量，有助于改善患者及其照料者的生活质量。SOBI公司已计划在2015年下半年将Orfadin口服混悬液推向整个欧盟市场。
遗传性酪氨酸血症I型（HT-1）是由于酪氨酸代谢过程的终末酶延胡索酰乙酰乙酸水解酶（FAH）编码基因发生突变以致FAH活性降低或缺失，酪氨酸分解代谢发生障碍，中间代谢产物如马来酰乙酰乙酸、延胡索酰乙酰乙酸、琥珀酰乙酰乙酸及琥珀酰丙酮等有毒副产物在体内蓄积，造成机体损伤，导致患儿肝功能衰竭、肾功能不全和神经系统并发症，症状在婴儿出生6个月内出现。
Orfadin（nitisinone）能够阻断酪氨酸的分解，从而减少体内有毒副产物的量
注：本品属瑞典原研药品，采购以咨询为准
Orfadin 4mg/ml Oral Suspension
1. Name of the medicinal product
Orfadin 4 mg/ml oral suspension
2. Qualitative and quantitative composition
1 ml contains 4 mg of nitisinone.
Excipients with known effect:
Each ml contains:
sodium 0.7 mg (0.03 mmol)
glycerol 500 mg
sodium benzoate 1 mg
For the full list of excipients, see section 6.1.
3. Pharmaceutical form
Oral suspension.
White, slightly viscous opaque suspension.
4. Clinical particulars
4.1 Therapeutic indications
Treatment of adult and paediatric (in any age range) patients with confirmed diagnosis of hereditary tyrosinemia type 1 (HT-1) in combination with dietary restriction of tyrosine and phenylalanine.
4.2 Posology and method of administration
Nitisinone treatment should be initiated and supervised by a physician experienced in the treatment of HT-1 patients.
Posology
Treatment of all genotypes of the disease should be initiated as early as possible to increase overall survival and avoid complications such as liver failure, liver cancer and renal disease. Adjunct to the nitisinone treatment, a diet deficient in phenylalanine and tyrosine is required and should be followed by monitoring of plasma amino acids (see sections 4.4 and 4.8).
The recommended initial dose in the paediatric and adult population is 1 mg/kg body weight/day divided in 2 doses administered orally. The dose of nitisinone should be adjusted individually.
Dose adjustment
During regular monitoring, it is appropriate to follow urine succinylacetone, liver function test values and alpha-fetoprotein levels (see section 4.4). If urine succinylacetone is still detectable one month after the start of nitisinone treatment, the nitisinone dose should be increased to 1.5 mg/kg body weight/day divided in 2 doses. A dose of 2 mg/kg body weight/day may be needed based on the evaluation of all biochemical parameters. This dose should be considered as a maximal dose for all patients.
If the biochemical response is satisfactory, the dose should be adjusted only according to body weight gain.
However, in addition to the tests above, during the initiation of therapy or if there is a deterioration, it may be necessary to follow more closely all available biochemical parameters (i.e. plasma succinylacetone, urine 5-aminolevulinate (ALA) and erythrocyte porphobilinogen (PBG)-synthase activity).
Special populations
There are no specific dose recommendations for elderly or patients that have renal or hepatic impairment.
Paediatric population
The dose recommendation in mg/kg body weight is the same in children and adults.
Method of administration
The suspension is administered in the patient's mouth with an oral syringe without dilution. A 1 ml, 3 ml and 5 ml oral syringes are included in the pack to measure the dose in ml in accordance with the prescribed posology. The oral syringes are graduated in 0.01 ml, 0.1 ml and 0.2 ml steps respectively. The table below shows the dose conversion (mg/ml) for the three oral syringes sizes.
Dose conversion tables respectively for the three oral syringe sizes:

Important information about instructions for use:
Re-dispersing is required before each use by vigorous shaking. Before re-dispersion, the medicinal product may appear as a solid cake with a slightly opalescent supernatant. The dose should be withdrawn and administered immediately after re-dispersion.
It is important to carefully follow the instructions given in section 6.6 for preparation and administration of the dose, in order to ensure the dosing accuracy.
It is recommended that the healthcare professional advises the patient or care giver how to use the oral syringes to ensure that the correct volume is administered and that the prescription is given in ml.
Orfadin is also available in 2 mg, 5 mg, 10 mg and 20 mg capsules, if considered more suitable for the patient.
It is recommended that the oral suspension is taken with food, see section 4.5.
Precautions to be taken before handling or administering the medicinal product
No needle, intravenous tubing or any other device for parenteral administration should be attached to the oral syringe.
Orfadin is for oral use only.
4.3 Contraindications
Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.
Mothers receiving nitisinone must not breast-feed (see sections 4.6 and 5.3).
4.4 Special warnings and precautions for use
Monitoring of plasma tyrosine levels
It is recommended that a slit-lamp examination of the eyes is performed before initiation of nitisinone treatment. A patient displaying visual disorders during treatment with nitisinone should without delay be examined by an ophthalmologist. It should be established that the patient is adhering to his/her dietary regimen and the plasma tyrosine concentration should be measured. A more restricted tyrosine and phenylalanine diet should be implemented in case the plasma tyrosine level is above 500 micromol/l. It is not recommended to lower the plasma tyrosine concentration by reduction or discontinuation of nitisinone, since the metabolic defect may result in deterioration of the patient's clinical condition.
Liver monitoring
The liver function should be monitored regularly by liver function tests and liver imaging. It is recommended to also monitor serum alpha-fetoprotein concentrations. Increase in serum alpha-fetoprotein concentration may be a sign of inadequate treatment. Patients with increasing alpha-fetoprotein or signs of nodules in the liver should always be evaluated for hepatic malignancy.
Platelet and white blood cell (WBC) monitoring
It is recommended that platelet and WBC counts are monitored regularly, as a few cases of reversible thrombocytopenia and leucopenia were observed during clinical evaluation.
Monitoring visits should be performed every 6 months; shorter intervals between visits are recommended in case of adverse events.
Excipients with known effect:
Glycerol
Each ml contains 500 mg. A dose of 20 ml oral suspension (10 g glycerol) or more may cause headache, stomach upset and diarrhoea.
Sodium
Each ml contains 0.7 mg (0.03 mmol).
Sodium benzoate
Each ml contains 1 mg. Increase in bilirubin following its displacement from albumin, caused by benzoic acid and its salts, may increase jaundice in pre-term and full-term jaundiced neonates and develop into kernicterus (unconjugated bilirubin deposits in the brain tissue). A close monitoring of the plasma levels of bilirubin in the newborn patient is therefore of great importance. Bilirubin levels should be measured before start of treatment: in case of markedly elevated plasma levels of bilirubin, especially in premature patients with risk factors as acidosis and low albumin level, treatment with an appropriately weighed portion of an Orfadin capsule should be considered instead of the oral suspension until the unconjugated bilirubin plasma levels are normalised.
4.5 Interaction with other medicinal products and other forms of interaction
No formal interaction studies with other medicinal products have been conducted.
Nitisinone is metabolised in vitro by CYP 3A4 and dose-adjustment may therefore be needed when nitisinone is co-administered with inhibitors or inducers of this enzyme.
Based on in vitro studies, nitisinone is not expected to inhibit CYP 1A2, 2C9, 2C19, 2D6, 2E1 or 3A4-mediated metabolism.
Food does not influence the bioavailability of nitisinone oral suspension, but intake together with food decreases the absorption rate and consequently leads to lower fluctuations in serum concentrations within a dosage interval. Therefore, it is recommended that the oral suspension is taken with food, see section 4.2.
4.6 Fertility, pregnancy and lactation
Pregnancy
There are no adequate data from the use of nitisinone in pregnant women. Studies in animals have shown reproductive toxicity (see section 5.3). The potential risk for humans is unknown. Orfadin should not be used during pregnancy unless the clinical condition of the woman requires treatment with nitisinone.
Breast-feeding
It is unknown whether nitisinone is excreted in human breast milk. Animal studies have shown adverse postnatal effects via exposure of nitisinone in milk. Therefore, mothers receiving nitisinone must not breast-feed, since a risk to the suckling child cannot be excluded (see sections 4.3 and 5.3).
Fertility
There are no data on nitisinone affecting fertility.
4.7 Effects on ability to drive and use machines
Orfadin has minor influence on the ability to drive and use machines. Adverse reactions involving the eyes (see section 4.8) can affect the vision. If the vision is affected the patient should not drive or use machines until the event has subsided.
4.8 Undesirable effects
Summary of the safety profile
By its mode of action, nitisinone increases tyrosine levels in all nitisinone treated patients. Eye-related adverse reactions, such as conjunctivitis, corneal opacity, keratitis, photophobia, and eye pain, related to elevated tyrosine levels are therefore common. Other common adverse reactions include thrombocytopenia, leucopenia, and granulocytopenia. Exfoliative dermatitis may occur uncommonly.
Tabulated list of adverse reactions
The adverse reactions listed below by MedDRA system organ class and absolute frequency, are based on data from a clinical trial and post-marketing use. Frequency is defined as very common (≥1/10), common (≥1/100 to <1/10), uncommon (≥1/1,000 to <1/100), rare (≥1/10,000 to <1/1,000), very rare (<1/10,000), not known (cannot be estimated from the available data). Within each frequency grouping, adverse reactions are presented in order of decreasing seriousness.

MedDRA system organ class	Frequency	Adverse reaction
Blood and lymphatic system disorders	Common	Thrombocytopenia, leucopenia, granulocytopenia
	Uncommon	Leukocytosis
Eye disorders	Common	Conjunctivitis, corneal opacity, keratitis, photophobia, eye pain
	Uncommon	Blepharitis
Skin and subcutaneous tissue disorders	Uncommon	Exfoliative dermatitis, erythematous rash, pruritus
Investigations	Very common	Elevated tyrosine levels

Description of selected adverse reactions
Nitisinone treatment leads to elevated tyrosine levels. Elevated levels of tyrosine have been associated with eye-related adverse reactions, such as e.g. corneal opacities and hyperkeratotic lesions. Restriction of tyrosine and phenylalanine in the diet should limit the toxicity associated with this type of tyrosinemia by lowering tyrosine levels (see section 4.4).
In clinical studies, granulocytopenia was only uncommonly severe (<0.5x109/L) and not associated with infections. Adverse reactions affecting the MedDRA system organ class 'Blood and lymphatic system disorders' subsided during continued nitisinone treatment.
Paediatric population
The safety profile is mainly based on the paediatric population since nitisinone treatment should be started as soon as the diagnosis of hereditary tyrosinemia type 1 (HT-1) has been established. From clinical study and post marketing data there are no indications that the safety profile is different in different subsets of the paediatric population or different from the safety profile in adult patients.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via:
United Kingdom
Yellow Card Scheme
Website: www.mhra.gov.uk/yellowcard
Ireland
HPRA Pharmacovigilance
Earlsfort Terrace
IRL - Dublin 2
Tel: +353 1 6764971
Fax: +353 1 6762517
Website: www.hpra.ie
e-mail: medsafety@hpra.ie
4.9 Overdose
Accidental ingestion of nitisinone by individuals eating normal diets not restricted in tyrosine and phenylalanine will result in elevated tyrosine levels. Elevated tyrosine levels have been associated with toxicity to eyes, skin, and the nervous system. Restriction of tyrosine and phenylalanine in the diet should limit toxicity associated with this type of tyrosinemia. No information about specific treatment of overdose is available.
5. Pharmacological properties
5.1 Pharmacodynamic properties
Pharmacotherapeutic group: Other alimentary tract and metabolism products, Various alimentary tract and metabolism products, ATC code: A16A X04.
Mechanism of action
The biochemical defect in hereditary tyrosinemia type 1 (HT-1) is a deficiency of fumarylacetoacetate hydrolase, which is the final enzyme of the tyrosine catabolic pathway. Nitisinone is a competitive inhibitor of 4-hydroxyphenylpyruvate dioxygenase, an enzyme which precedes fumarylacetoacetate hydrolase in the tyrosine catabolic pathway. By inhibiting the normal catabolism of tyrosine in patients with HT-1, nitisinone prevents the accumulation of the toxic intermediates maleylacetoacetate and fumarylacetoacetate. In patients with HT-1, these intermediates are converted to the toxic metabolites succinylacetone and succinylacetoacetate. Succinylacetone inhibits the porphyrin synthesis pathway leading to the accumulation of 5-aminolevulinate.
Pharmacodynamic effects
Nitisinone treatment leads to normalised porphyrin metabolism with normal erythrocyte porphobilinogen synthase activity and urine 5-aminolevulinate, decreased urinary excretion of succinylacetone, increased plasma tyrosine concentration and increased urinary excretion of phenolic acids. Available data from a clinical study indicates that in more than 90% of the patients urine succinylacetone was normalized during the first week of treatment. Succinylacetone should not be detectable in urine or plasma when the nitisinone dose is properly adjusted.
Clinical efficacy and safety
When compared to data for historical controls, it can be seen that treatment with nitisinone together with dietary restriction results in a higher survival probability in all HT-1 phenotypes. This is seen in the following table:

Age at start of treatment or diagnosis	Survival probability
	Nitisinone treatment		Dietary control
	5 years	10 years	5 years	10 years
< 2 months	82	--	28	--
> 2-6 months	95	95	51	34
> 6 months	92	86	93	59

Treatment with nitisinone was also found to result in reduced risk for the development of hepatocellular carcinoma (2.3 to 3.7-fold) compared to historical data on treatment with dietary restriction alone. It was found that the early initiation of treatment resulted in a further reduced risk for the development of hepatocellular carcinoma (13.5-fold when initiated prior to the age of 12 months).
5.2 Pharmacokinetic properties
Formal absorption, distribution, metabolism and elimination studies have not been performed with nitisinone. In 10 healthy male volunteers, after administration of a single dose of nitisinone capsules (1 mg/kg body weight) the terminal half-life (median) of nitisinone in plasma was 54 hours (ranging from 39 to 86 hours). A population pharmacokinetic analysis has been conducted on a group of 207 HT-1 patients. The clearance and half-life were determined to be 0.0956 l/kg body weight/day and 52.1 hours respectively.
In vitro studies using human liver microsomes and cDNA-expressed P450 enzymes have shown limited CYP 3A4-mediated metabolism.
5.3 Preclinical safety data
Nitisinone has shown embryo-foetal toxicity in the mouse and rabbit at clinically relevant dose levels. In the rabbit, nitisinone induced a dose-related increase in malformations (umbilical hernia and gastroschisis) from a dose level 2.5-fold higher than the maximum recommended human dose (2 mg/kg/day).
A pre- and postnatal development study in the mouse showed statistically significantly reduced pup survival and pup growth during the weaning period at dose levels 125- and 25-fold higher, respectively, than the maximum recommended human dose, with a trend toward a negative effect on pup survival starting from the dose of 5 mg/kg/day. In rats, exposure via milk resulted in reduced mean pup weight and corneal lesions.
No mutagenic but a weak clastogenic activity was observed in in vitro studies. There was no evidence of in vivo genotoxicity (mouse micronucleus assay and mouse liver unscheduled DNA synthesis assay). Carcinogenicity studies have not been performed.
6. Pharmaceutical particulars
6.1 List of excipients
Hydroxypropylmethylcellulose
Glycerol
Polysorbate 80
Sodium benzoate (E211)
Citric acid monohydrate
Sodium citrate
Strawberry aroma (artificial)
Purified water
6.2 Incompatibilities
Not applicable.
6.3 Shelf life
2 years.
After first opening, the in-use stability is a single period of 2 months at a temperature not above 25°C, after which it must be discarded.
6.4 Special precautions for storage
Store in a refrigerator (2°C – 8°C). Do not freeze.
Store upright.
For storage conditions after first opening of the medicinal product, see section 6.3.
6.5 Nature and contents of container
100 ml brown glass bottle (type III) with a white child-resistant HDPE screw cap with sealing and tamper evidence. Each bottle contains 90 ml oral suspension.
Each pack contains one bottle, one LDPE bottle adapter and 3 polypropylene (PP) oral syringes (1 ml, 3 ml and 5 ml).
6.6 Special precautions for disposal and other handling
Re-dispersing is required before each use by vigorous shaking. Before re-dispersion, the medicinal product may appear as a solid cake with a slightly opalescent supernatant. The dose should be withdrawn and administered immediately after re-dispersion. It is important to carefully follow the instructions given below for preparation and administration of the dose, in order to ensure the dosing accuracy.
Three oral syringes (1 ml, 3 ml and 5 ml) are provided for accurate measurement of the prescribed dose. It is recommended that the healthcare professional advises the patient or carer giver how to use the oral syringes to ensure that the correct volume is administered.
How to prepare a new bottle of medicine for first time use:
Before taking the first dose, the bottle should be shaken vigorously since during long-term storage the particles will form a solid cake at the bottom of the bottle.

1. The bottle should be removed from the refrigerator, and the date when the bottle is removed from the refrigerator should be noted on the bottle label.
2. The bottle should be shaken vigourously for at least 20 seconds until the solid cake at the bottom of the bottle is completely dispersed (Figure A).
3. The child-resistant screw cap should be removed by pushing it down firmly and turning it anti-clockwise (Figure B).
4. The open bottle should be placed upright on a table, and the plastic adapter pushed firmly into the neck of the bottle as far as possible (Figure C). The bottle should be closed with the child resistant screw cap.
For subsequent dosing see the instructions below 'How to prepare a dose of medicine'
How to prepare a dose of medicine

1. The bottle should be shaken vigourously for at least 5 seconds (Figure D).
2. Immediately thereafter, the bottle should be opened by removing the child-resistant screw cap.
3. The plunger inside the oral syringe should be pushed fully down.
4. The bottle should be kept in an upright position and the oral syringe inserted firmly into the hole of the adaptor, at the top of the bottle (Figure E).
5. The bottle should be turned carefully upside down with the oral syringe in place (Figure F).
6. In order to withdraw the prescribed dose (ml), the plunger should be pulled down slowly until the top edge of the black ring is exactly level with the line marking the dose (Figure F). If any air bubbles are observed inside the filled oral syringe, the plunger should be pushed back up until the air bubbles are expelled. Then the plunger should be pulled down again until the top edge of the black ring is exactly level with the line marking the dose.
7. The bottle should be turned to an upright position again, and the oral syringe disconnected by gently twisting it out of the bottle.
8. The dose should be administered in the mouth immediately (without dilution) in order to avoid caking in the oral syringe. The oral syringe should be emptied slowly to allow swallowing; rapid squirting of the medicine may cause choking.
9. The child-resistant screw cap should be replaced directly after use. The bottle adapter should not be removed.
10. The bottle may be stored at a temperature not above 25°C or in the refrigerator.
Cleaning
Clean the oral syringe immediately with water. Separate barrel and plunger and rinse both with water. Shake off excess water and leave the disassembled oral syringe to dry until reassemble for next dosing occasion.
Disposal
Any unused medicinal product or waste material should be disposed of in accordance with local requirements.
7. Marketing authorisation holder
Swedish Orphan Biovitrum International AB
SE-112 76 Stockholm
Sweden
8. Marketing authorisation number(s)
EU/1/04/303/005
9. Date of first authorisation/renewal of the authorisation
Date of first authorisation: 21/02/2005
Date of latest renewal: 21/02/2010
10. Date of revision of the text
19.06.15
Detailed information on this medicinal product is available on the website of the European Medicines Agency http://www.ema.europa.eu.
注：以下是其他胶囊处方资料：
Orfadin 20mg Hard Capsule（https://www.medicines.org.uk/emc/medicine/30534）
Orfadin 2mg hard capsule（https://www.medicines.org.uk/emc/medicine/30535）
Orfadin 10 mg hard capsules（https://www.medicines.org.uk/emc/medicine/21408）
Orfadin 5mg capsules（https://www.medicines.org.uk/emc/medicine/21410）