Doses up to 10.5 times the intended dose have been reported. The maximum daily dose reported is 1,200 µg for one day. In general, the adverse events seen in overdose cases involving Intron A Peg are consistent with the known safety profile for Intron A Peg; however, the severity of the events may be increased. Standard methods to increase elimination of the medicinal product, e.g., dialysis, have not been shown to be useful. No specific antidote for Intron A Peg is available; therefore, symptomatic treatment and close observation of the patient are recommended in cases of overdose. If available, prescribers are advised to consult with a poison control centre (PCC).
- Hypersensitivity to the active substance or to any interferon or to any of the excipients listed in section 6.1;
- A history of severe pre-existing cardiac disease, including unstable or uncontrolled cardiac disease in the previous six months ;
- Severe, debilitating medical conditions;
- Autoimmune hepatitis or a history of autoimmune disease;
- Severe hepatic dysfunction or decompensated cirrhosis of the liver;
- Pre-existing thyroid disease unless it can be controlled with conventional treatment;
- Epilepsy and/or compromised central nervous system (CNS) function;
- HCV/HIV patients with cirrhosis and a Child-Pugh score > 6.
- Combination of Intron A Peg with telbivudine.
Paediatric population
- Existence of, or history of severe psychiatric condition, particularly severe depression, suicidal ideation or suicidal attempt.
Combination therapy
Also see SmPCs for ribavirin and boceprevir if Intron A Peg is to be administered in combination therapy in patients with chronic hepatitis C.
In the absence of compatibility studies, this medicinal product must not be mixed with other medicinal products.
Adults
Tritherapy
Refer to the SmPC for boceprevir.
Bitherapy and monotherapy
Summary of the safety profile
The most common treatment-related adverse reactions reported during clinical trials with Intron A Peg in combination with ribavirin in adults, seen in more than half of the study subjects, were fatigue, headache, and injection site reaction. Additional adverse reactions reported in more than 25 % of subjects included nausea, chills, insomnia, anaemia, pyrexia, myalgia, asthenia, pain, alopecia, anorexia, weight decreased, depression, rash and irritability. The most frequently reported adverse reactions were mostly mild to moderate in severity and were manageable without the need for modification of doses or discontinuation of therapy. Fatigue, alopecia, pruritus, nausea, anorexia, weight decreased, irritability and insomnia occur at a notably lower rate in patients treated with Intron A Peg monotherapy compared to those treated with combination therapy (see Table 6).
Tabulated summary of adverse reactions
The following treatment-related adverse reactions were reported in adults in clinical trials or through post-marketing surveillance in patients treated with peginterferon alfa-2b, including Intron A Peg monotherapy or Intron A Peg/ribavirin. These reactions are listed in table 6 by system organ class and frequency (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) or not known (cannot be estimated from the available data).
Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness.
Table 6 Adverse reactions reported in adults in clinical trials or through post-marketing surveillance in patients treated with peginterferon alfa-2b, including Intron A Peg monotherapy or Intron A Peg + ribavirin
| Infections and infestations | |
| Very common: | Viral infection*, pharyngitis* |
| Common: | Bacterial infection (including sepsis), fungal infection, influenza, upper respiratory tract infection, bronchitis, herpes simplex, sinusitis, otitis media, rhinitis |
| Uncommon: | Injection site infection, lower respiratory tract infection |
| Not known: | Hepatitis B reactivation in HCV/HBV co-infected patients |
| Blood and lymphatic system disorders | |
| Very common: | Anaemia, neutropenia |
| Common: | Haemolytic anaemia, leukopenia, thrombocytopenia, lymphadenopathy |
| Very rare: | Aplastic anaemia |
| Not known: | Aplasia pure red cell |
| Immune system disorders | |
| Uncommon: | Drug hypersensitivity |
| Rare: | Sarcoidosis |
| Not known: | Acute hypersensitivity reactions including angioedema, anaphylaxis and anaphylactic reactions including anaphylactic shock, idiopathic thrombocytopenic purpura, thrombotic thrombocytopenic purpura, systemic lupus erythematosus |
| Endocrine disorders | |
| Common: | Hypothyroidism, hyperthyroidism |
| Metabolism and nutrition disorders | |
| Very common: | Anorexia |
| Common: | Hypocalcemia, hyperuricemia, dehydration, increased appetite |
| Uncommon: | Diabetes mellitus, hypertriglyceridaemia |
| Rare: | Diabetic ketoacidosis |
| Psychiatric disorders | |
| Very common: | Depression, anxiety*, emotional lability*, concentration impaired, insomnia |
| Common: | Aggression, agitation, anger, mood altered, abnormal behaviour, nervousness, sleep disorder, libido decreased, apathy, abnormal dreams, crying |
| Uncommon: | Suicide, suicide attempt, suicidal ideation, psychosis, hallucination, panic attack |
| Rare: | Bipolar disorders |
| Not known: | Homicidal ideation, mania |
| Nervous system disorders | |
| Very common: | Headache, dizziness |
| Common: | Amnesia, memory impairment, syncope, migraine, ataxia, confusion, neuralgia, paraesthesia, hypoaesthesia, hyperaesthesia, hypertonia, somnolence, disturbance in attention, tremor, dysgeusia |
| Uncommon: | Neuropathy, neuropathy peripheral |
| Rare: | Convulsion |
| Very rare: | Cerebrovascular haemorrhage, cerebrovascular ischaemia, encephalopathy |
| Not known: | Facial palsy, mononeuropathies |
| Eye disorders | |
| Common: | Visual disturbance, vision blurred, photophobia, conjunctivitis, eye irritation, lacrimal disorder, eye pain, dry eye |
| Uncommon: | Retinal exudates |
| Rare: | Loss of visual acuity or visual fields, retinal haemorrhage, retinopathy, retinal artery occlusion, retinal vein occlusion, optic neuritis, papilloedema, macular oedema |
| Not known: | Serous retinal detachment |
| Ear and labyrinth disorders | |
| Common: | Hearing impaired/loss, tinnitus, vertigo |
| Uncommon | Ear pain |
| Cardiac disorders | |
| Common: | Palpitations, tachycardia |
| Uncommon: | Myocardial infarction |
| Rare: | Congestive heart failure, cardiomyopathy, arrhythmia, pericarditis |
| Very rare: | Cardiac ischaemia |
| Not known: | Pericardial effusion |
| Vascular disorders | |
| Common: | Hypotension, hypertension, flushing |
| Rare: | Vasculitis |
| Respiratory, thoracic and mediastinal disorders | |
| Very common: | Dyspnoea*, cough* |
| Common: | Dysphonia, epistaxis, respiratory disorder, respiratory tract congestion, sinus congestion, nasal congestion, rhinorrhea, increased upper airway secretion, pharyngolaryngeal pain |
| Very rare: | Interstitial lung disease |
| Not known: | Pulmonary fibrosis, pulmonary arterial hypertension# |
| Gastrointestinal disorders | |
| Very common: | Vomiting*, nausea, abdominal pain, diarrhoea, dry mouth* |
| Common: | Dyspepsia, gastroesophageal reflux disease, stomatitis, mouth ulceration, glossodynia, gingival bleeding, constipation, flatulence, haemorrhoids, cheilitis, abdominal distension, gingivitis, glossitis, tooth disorder |
| Uncommon: | Pancreatitis, oral pain |
| Rare: | Colitis ischaemic |
| Very rare: | Colitis ulcerative |
| Not known | Tongue pigmentation |
| Hepatobiliary disorders | |
| Common: | Hyperbilirubinemia, hepatomegaly |
| Skin and subcutaneous tissue disorders | |
| Very common: | Alopecia, pruritus*, dry skin*, rash* |
| Common: | Psoriasis, photosensitivity reaction, rash maculo-papular, dermatitis, erythematous rash, eczema, night sweats, hyperhidrosis, acne, furuncle, erythema, urticaria, abnormal hair texture, nail disorder |
| Rare: | Cutaneous sarcoidosis |
| Very rare: | Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme |
| Musculoskeletal and connective tissue disorders | |
| Very common: | Myalgia, arthralgia, musculoskeletal pain |
| Common: | Arthritis, back pain, muscle spasms, pain in extremity |
| Uncommon: | Bone pain, muscle weakness |
| Rare: | Rhabdomyolysis, myositis, rheumatoid arthritis |
| Renal and urinary disorders | |
| Common: | Micturition frequency, polyuria, urine abnormality |
| Rare: | Renal failure, renal insufficiency |
| Reproductive system and breast disorders | |
| Common: | Amenorrhoea, breast pain, menorrhagia, menstrual disorder, ovarian disorder, vaginal disorder, sexual dysfunction, prostatitis, erectile dysfunction |
| General disorders and administration site conditions | |
| Very common: | Injection site reaction*, injection site inflammation, fatigue, asthenia, irritability, chills, pyrexia, influenza like illness, pain |
| Common: | Chest pain, chest discomfort, injection site pain, malaise, face oedema, oedema peripheral, feeling abnormal, thirst |
| Rare: | Injection site necrosis |
| Investigations | |
| Very common: | Weight decreased |
*These adverse reactions were common (>1/100 to < 1/10) in clinical trials in patients treated with Intron A Peg monotherapy.
#Class label for interferon products, see below Pulmonary arterial hypertension.
Description of selected adverse reactions in adults
Most cases of neutropenia and thrombocytopenia were mild (WHO grades 1 or 2). There were some cases of more severe neutropenia in patients treated with the recommended doses of Intron A Peg in combination with ribavirin (WHO grade 3: 39 of 186 [21 %]; and WHO grade 4: 13 of 186 [7 %]).
In a clinical trial, approximately 1.2 % of patients treated with Intron A Peg or interferon alfa-2b in combination with ribavirin reported life-threatening psychiatric events during treatment. These events included suicidal ideation and attempted suicide.
Cardiovascular (CVS) adverse events, particularly arrhythmia, appeared to be correlated mostly with pre-existing CVS disease and prior therapy with cardiotoxic agents. Cardiomyopathy, that may be reversible upon discontinuation of interferon alpha, has been reported rarely in patients without prior evidence of cardiac disease.
Cases of pulmonary arterial hypertension (PAH) have been reported with interferon alfa products, notably in patients with risk factors for PAH (such as portal hypertension, HIV-infection, cirrhosis). Events were reported at various time points typically several months after starting treatment with interferon alfa.
Ophthalmological disorders that have been reported rarely with alpha interferons include retinopathies (including macular oedema), retinal haemorrhages, retinal artery or vein occlusion, retinal exudates, loss of visual acuity or visual field, optic neuritis, and papilloedema.
HCV/HIV co-infected patients
Summary of the safety profile
For HCV/HIV co-infected patients receiving Intron A Peg in combination with ribavirin, other undesirable effects (that were not reported in mono-infected patients) which have been reported in the larger studies with a frequency > 5 % were: oral candidiasis (14 %), lipodystrophy acquired (13 %), CD4 lymphocytes decreased (8 %), appetite decreased (8 %), gamma-glutamyltransferase increased (9 %), back pain (5 %), blood amylase increased (6 %), blood lactic acid increased (5 %), cytolytic hepatitis (6 %), lipase increased (6 %) and pain in limb (6 %).
Description of selected adverse reactions
Mitochondrial toxicity
Mitochondrial toxicity and lactic acidosis have been reported in HIV-positive patients receiving NRTI regimen and associated ribavirin for co-HCV infection.
Laboratory values for HCV/HIV co-infected patients
Although haematological toxicities of neutropenia, thrombocytopenia and anaemia occurred more frequently in HCV/HIV co-infected patients, the majority could be managed by dose modification and rarely required premature discontinuation of treatment. Haematological abnormalities were more frequently reported in patients receiving Intron A Peg in combination with ribavirin when compared to patients receiving interferon alfa-2b in combination with ribavirin. In Study 1 , decrease in absolute neutrophil count levels below 500 cells/mm3 was observed in 4 % (8/194) of patients and decrease in platelets below 50,000/mm3 was observed in 4 % (8/194) of patients receiving Intron A Peg in combination with ribavirin. Anaemia (hemoglobin < 9.4 g/dl) was reported in 12 % (23/194) of patients treated with Intron A Peg in combination with ribavirin.
CD4 lymphocytes decrease
Treatment with Intron A Peg in combination with ribavirin was associated with decreases in absolute CD4+ cell counts within the first 4 weeks without a reduction in CD4+ cell percentage. The decrease in CD4+ cell counts was reversible upon dose reduction or cessation of therapy. The use of Intron A Peg in combination with ribavirin had no observable negative impact on the control of HIV viraemia during therapy or follow-up. Limited safety data (N= 25) are available in co-infected patients with CD4+ cell counts < 200/µl.
Please refer to the respective SmPCs of the antiretroviral medicinal products that are to be taken concurrently with HCV therapy for awareness and management of toxicities specific for each product and the potential for overlapping toxicities with Intron A Peg in combination with ribavirin.
Paediatric population
Summary of the safety profile
In a clinical trial with 107 children and adolescent patients (3 to 17 years of age) treated with combination therapy of Intron A Peg and ribavirin, dose modifications were required in 25 % of patients, most commonly for anaemia, neutropenia and weight loss. In general, the adverse reactions profile in children and adolescents was similar to that observed in adults, although there is a paediatric-specific concern regarding growth inhibition. During combination therapy for up to 48 weeks with Intron A Peg and ribavirin, growth inhibition was observed that resulted in reduced height in some patients. Weight loss and growth inhibition were very common during the treatment (at the end of treatment, mean decrease from baseline in weight and height percentile were of 15 percentiles and 8 percentiles, respectively) and growth velocity was inhibited (< 3rd percentile in 70 % of the patients).
At the end of 24 weeks post-treatment follow-up, mean decrease from baseline in weight and height percentiles were still of 3 percentiles and 7 percentiles respectively, and 20 % of the children continued to have inhibited growth (growth velocity < 3rd percentile). Ninety-four of 107 subjects enrolled in the 5 year long-term follow-up trial. The effects on growth were less in those subjects treated for 24 weeks than those treated for 48 weeks. From pre-treatment to end of long-term follow-up among subjects treated for 24 or 48 weeks, height-for-age percentiles decreased 1.3 and 9.0 percentiles, respectively. Twenty-four percent of subjects (11/46) treated for 24 weeks and 40 % of subjects (19/48) treated for 48 weeks had a > 15 percentile height-for-age decrease from pre-treatment to the end of the 5 year long-term follow-up compared to pre-treatment baseline percentile. Eleven percent of subjects (5/46) treated for 24 weeks and 13 % of subjects (6/48) treated for 48 weeks were observed to have a decrease from pre-treatment baseline of > 30 height-for-age percentiles to the end of the 5 year long-term follow-up. For weight, pre-treatment to end of long-term follow-up, weight-for-age percentiles decreased 1.3 and 5.5 percentiles among subjects treated for 24 weeks or 48 weeks, respectively. For BMI, pre-treatment to end of long-term follow-up, BMI-for-age percentiles decreased 1.8 and 7.5 percentiles among subjects treated for 24 weeks or 48 weeks, respectively.
Decrease in mean height percentile at year 1 of long-term follow-up was most prominent in prepubertal age children. The decline of height, weight and BMI Z scores observed during the treatment phase in comparison to a normative population did not fully recover at the end of long-term follow-up period for children treated with 48 weeks of therapy.
In the treatment phase of this study, the most prevalent adverse reactions in all subjects were pyrexia (80 %), headache (62 %), neutropenia (33 %), fatigue (30 %), anorexia (29 %) and injection-site erythema (29 %). Only 1 subject discontinued therapy as the result of an adverse reaction (thrombocytopenia). The majority of adverse reactions reported in the study were mild or moderate in severity. Severe adverse reactions were reported in 7 % (8/107) of all subjects and included injection site pain (1 %), pain in extremity (1 %), headache (1 %), neutropenia (1 %), and pyrexia (4 %). Important treatment-emergent adverse reactions that occurred in this patient population were nervousness (8 %), aggression (3 %), anger (2 %), depression/depressed mood (4 %) and hypothyroidism (3 %) and 5 subjects received levothyroxine treatment for hypothyroidism/elevated TSH.
Tabulated summary of adverse reactions
The following treatment-related adverse reactions were reported in the study in children and adolescent patients treated with Intron A Peg in combination with ribavirin. These reactions are listed in Table 7 by system organ class and frequency (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) or not known (cannot be estimated from the available data).
Within each frequency grouping, adverse reactions are presented in order of decreasing seriousness.
Table 7 Adverse reactions very commonly, commonly and uncommonly reported in the clinical trial in children and adolescent patients treated with Intron A Peg in combination with ribavirin
| Infections and infestations | |
| Common: | Fungal infection, influenza, oral herpes, otitis media, pharyngitis streptococcal, nasopharyngitis, sinusitis |
| Uncommon: | Pneumonia, ascariasis, enterobiasis, herpes zoster, cellulitis, urinary tract infection, gastroenteritis |
| Blood and lymphatic system disorders | |
| Very common: | Anaemia, leucopenia, neutropenia |
| Common: | Thrombocytopenia, lymphadenopathy |
| Endocrine disorders | |
| Common: | Hypothyroidism |
| Metabolism and nutrition disorders | |
| Very common: | Anorexia, decreased appetite |
| Psychiatric disorders | |
| Common: | Suicidal ideation§, suicide attempt§, depression, aggression, affect lability, anger, agitation, anxiety, mood altered, restlessness, nervousness, insomnia |
| Uncommon: | Abnormal behaviour, depressed mood, emotional disorder, fear, nightmare |
| Nervous system disorders | |
| Very common: | Headache, dizziness |
| Common: | Dysgeusia, syncope, disturbance in attention, somnolence, poor quality sleep |
| Uncommon: | Neuralgia, lethargy, paraesthesia, hypoaesthesia, psychomotor hyperactivity, tremor |
| Eye disorders | |
| Common: | Eye pain |
| Uncommon: | Conjunctival haemorrhage, eye pruritus, keratitis, vision blurred, photophobia |
| Ear and labyrinth disorders | |
| Common: | Vertigo |
| Cardiac disorders | |
| Common: | Palpitations, tachycardia |
| Vascular disorders | |
| Common: | Flushing |
| Uncommon: | Hypotension, pallor |
| Respiratory, thoracic and mediastinal disorders | |
| Common: | Cough, epistaxis, pharyngolaryngeal pain |
| Uncommon: | Wheezing, nasal discomfort, rhinorrhoea |
| Gastrointestinal disorders | |
| Very common: | Abdominal pain, abdominal pain upper, vomiting, nausea |
| Common: | Diarrhoea, aphthous stomatitis, cheilosis, mouth ulceration, stomach discomfort, oral pain |
| Uncommon: | Dyspepsia, gingivitis |
| Hepatobiliary disorders | |
| Uncommon: | Hepatomegaly |
| Skin and subcutaneous tissue disorders | |
| Very common: | Alopecia, dry skin |
| Common: | Pruritus, rash, rash erythematous, eczema, acne, erythema |
| Uncommon: | Photosensitivity reaction, rash maculo-papular, skin exfoliation, pigmentation disorder, dermatitis atopic, skin discolouration |
| Musculoskeletal and connective tissue disorders | |
| Very common: | Myalgia, arthralgia |
| Common: | Musculoskeletal pain, pain in extremity, back pain |
| Uncommon: | Muscle contracture, muscle twitching |
| Renal and urinary disorders | |
| Uncommon: | Proteinuria |
| Reproductive system and breast disorders | |
| Uncommon: | Female: Dysmenorrhoea |
| General disorders and administration site conditions | |
| Very common: | Injection site erythema, fatigue, pyrexia, rigors, influenza-like illness, asthenia, pain, malaise, irritability |
| Common: | Injection site reaction, injection site pruritus, injection site rash injection site dryness, injection site pain, feeling cold |
| Uncommon: | Chest pain, chest discomfort, facial pain |
| Investigations | |
| Very common: | Growth rate decrease (height and/or weight decrease for age) |
| Common: | Blood thyroid stimulating hormone increased, thyroglobulin increased |
| Uncommon: | Anti-thyroid antibody positive |
| Injury and poisoning | |
| Uncommon: | Contusion |
§class effect of interferon-alfa containing products - reported with standard interferon therapy in adult and paediatric patients; with Intron A Peg reported in adult patients.
Description of selected adverse reactions in children and adolescents
Most of the changes in laboratory values in the Intron A Peg/ribavirin clinical trial were mild or moderate. Decreases in haemoglobin, white blood cells, platelets, neutrophils and increase in bilirubin may require dose reduction or permanent discontinuation from therapy. While changes in laboratory values were observed in some patients treated with Intron A Peg used in combination with ribavirin in the clinical trial, values returned to baseline levels within a few weeks after the end of therapy.
Reporting of
Intron A Peg
Adverse events not observed in clinical trials were not seen in toxicity studies in monkeys. These studies were limited to four weeks due to the appearance of anti-interferon antibodies in most monkeys.
Reproduction studies of Intron A Peg have not been performed.). Intron A Peg showed no genotoxic potential.
The relative non-toxicity of monomethoxy-polyethylene glycol (mPEG), which is liberated from Intron A Peg by metabolism in vivo has been demonstrated in preclinical acute and subchronic toxicity studies in rodents and monkeys, standard embryo-foetal development studies and in in vitro mutagenicity assays.
Intron A Peg plus ribavirin
When used in combination with ribavirin, Intron A Peg did not cause any effects not previously seen with either active substance alone. The major treatment-related change was a reversible, mild to moderate anaemia, the severity of which was greater than that produced by either active substance alone.
No studies have been conducted in juvenile animals to examine the effects of treatment with Intron A Peg on growth, development, sexual maturation, and behaviour.).
Adults (tritherapy)
Intron A Peg in combination with ribavirin and boceprevir (tritherapy) is indicated for the treatment of chronic hepatitis C (CHC) genotype 1 infection in adult patients (18 years of age and older) with compensated liver disease who are previously untreated or who have failed previous therapy.
Please refer to the ribavirin and boceprevir Summary of Product Characteristics (SmPCs) when Intron A Peg is to be used in combination with these medicines.
Adults (bitherapy and monotherapy)
Intron A Peg is indicated for the treatment of adult patients (18 years of age and older) with CHC who are positive for hepatitis C virus RNA (HCV-RNA), including patients with compensated cirrhosis and/or co-infected with clinically stable HIV.
Intron A Peg in combination with ribavirin (bitherapy) is indicated for the treatment of CHC infection in adult patients who are previously untreated including patients with clinically stable HIV co-infection and in adult patients who have failed previous treatment with interferon alpha (pegylated or nonpegylated) and ribavirin combination therapy or interferon alpha monotherapy.
Interferon monotherapy, including Intron A Peg, is indicated mainly in case of intolerance or contraindication to ribavirin.
Please refer to the ribavirin SmPC when Intron A Peg is to be used in combination with ribavirin.
Paediatric population (bitherapy)
Intron A Peg is indicated in a combination regimen with ribavirin for the treatment of children 3 years of age and older and adolescents, who have chronic hepatitis C, previously untreated, without liver decompensation, and who are positive for HCV-RNA.
When deciding not to defer treatment until adulthood, it is important to consider that the combination therapy induced a growth inhibition that may be irreversible in some patients. The decision to treat should be made on a case by case basis.
Please refer to the ribavirin SmPC for capsules or oral solution when Intron A Peg is to be used in combination with ribavirin.
Pharmacotherapeutic group: Immunostimulants, Interferons, ATC code: L03AB10.
Recombinant interferon alfa-2b is covalently conjugated with monomethoxy polyethylene glycol at an average degree of substitution of 1 mole of polymer/mole of protein. The average molecular mass is approximately 31,300 daltons of which the protein moiety constitutes approximately 19,300.
Mechanism of action
In vitro and in vivo studies suggest that the biological activity of Intron A Peg is derived from its interferon alfa-2b moiety.
Interferons exert their cellular activities by binding to specific membrane receptors on the cell surface. Studies with other interferons have demonstrated species specificity. However, certain monkey species, e.g., Rhesus monkeys are susceptible to pharmacodynamic stimulation upon exposure to human type 1 interferons.
Once bound to the cell membrane, interferon initiates a complex sequence of intracellular events that include the induction of certain enzymes. It is thought that this process, at least in part, is responsible for the various cellular responses to interferon, including inhibition of virus replication in virus-infected cells, suppression of cell proliferation and such immunomodulating activities as enhancement of the phagocytic activity of macrophages and augmentation of the specific cytotoxicity of lymphocytes for target cells. Any or all of these activities may contribute to interferon's therapeutic effects.
Recombinant interferon alfa-2b also inhibits viral replication in vitro and in vivo. Although the exact antiviral mode of action of recombinant interferon alfa-2b is unknown, it appears to alter the host cell metabolism. This action inhibits viral replication or if replication occurs, the progeny virions are unable to leave the cell.
Pharmacodynamic effects
Intron A Peg pharmacodynamics were assessed in a rising single-dose trial in healthy subjects by examining changes in oral temperature, concentrations of effector proteins such as serum neopterin and 2'5'-oligoadenylate synthetase (2'5'-OAS), as well as white cell and neutrophil counts. Subjects treated with Intron A Peg showed mild dose-related elevations in body temperature. Following single doses of Intron A Peg between 0.25 and 2.0 micrograms/kg/week, serum neopterin concentration was increased in a dose-related manner. Neutrophil and white cell count reductions at the end of week 4 correlated with the dose of Intron A Peg.
Clinical efficacy and safety - Adults
Tritherapy with Intron A Peg, ribavirin and boceprevir
Refer to the SmPC for boceprevir.
Monotherapy with Intron A Peg and bitherapy with Intron A Peg and ribavirin
Naïve patients
Two pivotal trials have been conducted, one (C/I97-010) with Intron A Peg monotherapy; the other (C/I98-580) with Intron A Peg in combination with ribavirin. Eligible patients for these trials had chronic hepatitis C confirmed by a positive HCV-RNA polymerase chain reaction (PCR) assay (> 30 IU/ml), a liver biopsy consistent with a histological diagnosis of chronic hepatitis with no other cause for the chronic hepatitis, and abnormal serum ALT.
In the Intron A Peg monotherapy trial, a total of 916 naïve chronic hepatitis C patients were treated with Intron A Peg (0.5, 1.0 or 1.5 micrograms/kg/week) for one year with a follow-up period of six months. In addition, 303 patients received interferon alfa-2b (3 million International Units [MIU] three times a week) as a comparator. This study showed that Intron A Peg was superior to interferon alfa-2b (Table 8).
In the Intron A Peg combination trial, 1,530 naïve patients were treated for one year with one of the following combination regimens:
- Intron A Peg (1.5 micrograms/kg/week) + ribavirin (800 mg/day), (n = 511).
- Intron A Peg (1.5 micrograms/kg/week for one month followed by 0.5 microgram/kg/week for 11 months) + ribavirin (1,000/1,200 mg/day), (n = 514).
- Interferon alfa-2b (3 MIU three times a week) + ribavirin (1,000/1,200 mg/day) (n = 505).
In this trial, the combination of Intron A Peg (1.5 micrograms/kg/week) and ribavirin was significantly more effective than the combination of interferon alfa-2b and ribavirin (Table 8), particularly in patients infected with Genotype 1 (Table 9). Sustained response was assessed by the response rate six months after the cessation of treatment.
HCV genotype and baseline virus load are prognostic factors which are known to affect response rates. However, response rates in this trial were shown to be dependent also on the dose of ribavirin administered in combination with Intron A Peg or interferon alfa-2b. In those patients that received > 10.6 mg/kg ribavirin (800 mg dose in typical 75 kg patient), regardless of genotype or viral load, response rates were significantly higher than in those patients that received ≤ 10.6 mg/kg ribavirin (Table 9), while response rates in patients that received > 13.2 mg/kg ribavirin were even higher.
Table 8 Sustained virological response (% patients HCV negative)
| Intron A Peg monotherapy | Intron A Peg + ribavirin | ||||||
| Treatment regimen | P 1.5 | P 1.0 | P 0.5 | I | P 1.5/R | P 0.5/R | I/R |
| Number of patients | 304 | 297 | 315 | 303 | 511 | 514 | 505 |
| Response at end of treatment | 49 % | 41 % | 33 % | 24 % | 65 % | 56 % | 54 % |
| Sustained response | 23 %* | 25 % | 18 % | 12 % | 54 %** | 47 % | 47 % |
| P 1.5 P 1.0 P 0.5 I P 1.5/R P 0.5/R I/R * ** | Intron A Peg 1.5 micrograms/kg Intron A Peg 1.0 microgram/kg Intron A Peg 0.5 microgram/kg Interferon alfa-2b 3 MIU Intron A Peg (1.5 micrograms/kg) + ribavirin (800 mg) Intron A Peg (1.5 to 0.5 microgram/kg) + ribavirin (1,000/1,200 mg) Interferon alfa-2b (3 MIU) + ribavirin (1,000/1,200 mg) p < 0.001 P 1.5 vs. I p = 0.0143 P 1.5/R vs. I/R |
Table 9 Sustained response rates with Intron A Peg + ribavirin (by ribavirin dose, genotype and viral load)
| HCV Genotype | Ribavirin dose (mg/kg) | P 1.5/R | P 0.5/R | I/R |
| All Genotypes | All | 54 % | 47 % | 47 % |
| ≤ 10.6 | 50 % | 41 % | 27 % | |
| > 10.6 | 61 % | 48 % | 47 % | |
| Genotype 1 | All | 42 % | 34 % | 33 % |
| ≤ 10.6 | 38 % | 25 % | 20 % | |
| > 10.6 | 48 % | 34 % | 34 % | |
| Genotype 1 ≤ 600,000 IU/ml | All | 73 % | 51 % | 45 % |
| ≤ 10.6 | 74 % | 25 % | 33 % | |
| > 10.6 | 71 % | 52 % | 45 % | |
| Genotype 1 > 600,000 IU/ml | All | 30 % | 27 % | 29 % |
| ≤ 10.6 | 27 % | 25 % | 17 % | |
| > 10.6 | 37 % | 27 % | 29 % | |
| Genotype 2/3 | All | 82 % | 80 % | 79 % |
| ≤ 10.6 | 79 % | 73 % | 50 % | |
| > 10.6 | 88 % | 80 % | 80 % |
| P 1.5/R P 0.5/R I/R | Intron A Peg (1.5 micrograms/kg) + ribavirin (800 mg) Intron A Peg (1.5 to 0.5 microgram/kg) + ribavirin (1,000/1,200 mg) Interferon alfa-2b (3 MIU) + ribavirin (1,000/1,200 mg) |
In the Intron A Peg monotherapy study, the Quality of Life was generally less affected by 0.5 microgram/kg of Intron A Peg than by either 1.0 microgram/kg of Intron A Peg once weekly or 3 MIU of interferon alfa-2b three times a week.
In a separate trial, 224 patients with genotype 2 or 3 received Intron A Peg, 1.5 micrograms/kg subcutaneously, once weekly, in combination with ribavirin 800 mg -1,400 mg p.o. for 6 months (based on body weight, only three patients weighing > 105 kg, received the 1,400 mg dose) (Table 10). Twenty-four % had bridging fibrosis or cirrhosis (Knodell 3/4).
Table 10 Virologic response at end of treatment, Sustained Virologic Response and relapse by HCV Genotype and viral load*
| Intron A Peg 1.5 μg/kg once weekly plus Ribavirin 800-1,400 mg/day | |||
| End of treatment response | Sustained Virologic Response | Relapse | |
| All subjects | 94 % (211/224) | 81 % (182/224) | 12 % (27/224) |
| HCV 2 | 100 % (42/42) | 93 % (39/42) | 7 % (3/42) |
| ≤ 600,000 IU/ml | 100 % (20/20) | 95 % (19/20) | 5 % (1/20) |
| > 600,000 IU/ml | 100 % (22/22) | 91 % (20/22) | 9 % (2/22) |
| HCV 3 | 93 % (169/182) | 79 % (143/182) | 14 % (24/166) |
| ≤ 600,000 IU/ml | 93 % (92/99) | 86 % (85/99) | 8 % (7/91) |
| > 600,000 IU/ml | 93 % (77/83) | 70 % (58/83) | 23 % (17/75) |
* Any subject with an undetectable HCV-RNA level at the follow-up week 12 visit and missing data at the follow-up week 24 visit was considered a sustained responder. Any subject with missing data in and after the follow-up week 12 window was considered to be a non-responder at week 24 of follow-up.
The 6 month treatment duration in this trial was better tolerated than one year of treatment in the pivotal combination trial; for discontinuation 5 % vs. 14 %, for dose modification 18 % vs. 49 %.
In a non-comparative trial, 235 patients with genotype 1 and low viral load (< 600,000 IU/ml) received Intron A Peg, 1.5 micrograms/kg subcutaneously, once weekly, in combination with weight adjusted ribavirin. The overall sustained response rate after a 24-week treatment duration was 50 %. Forty-one percent of subjects (97/235) had nondetectable plasma HCV-RNA levels at week 4 and week 24 of therapy. In this subgroup, there was a 92 % (89/97) sustained virological response rate. The high sustained response rate in this subgroup of patients was identified in an interim analysis (n=49) and prospectively confirmed (n=48).
Limited historical data indicate that treatment for 48 weeks might be associated with a higher sustained response rate (11/11) and with a lower risk of relapse (0/11 as compared to 7/96 following 24 weeks of treatment).
A large randomized trial compared the safety and efficacy of treatment for 48 weeks with two Intron A Peg/ribavirin regimens [Intron A Peg 1.5 µg/kg and 1 µg/kg subcutaneously once weekly both in combination with ribavirin 800 to 1,400 mg p.o. daily (in two divided doses)] and peginterferon alfa-2a 180 µg subcutaneously once weekly with ribavirin 1,000 to 1,200 mg p.o. daily (in two divided doses) in 3,070 treatment-naïve adults with chronic hepatitis C genotype 1. Response to the treatment was measured by Sustained Virologic Response (SVR) which is defined as undetectable HCV-RNA at 24 weeks post-treatment (see Table 11).
Table 11 Virologic response at treatment week 12, end of treatment response, relapse rate *and Sustained Virologic Response (SVR)
| Treatment group | % (number) of patients | ||
| Intron A Peg 1.5 µg/kg + ribavirin | Intron A Peg 1 µg/kg + ribavirin | peginterferon alfa-2a 180 µg + ribavirin | |
| Undetectable HCV-RNA at treatment week 12 | 40 (407/1,019) | 36 (366/1,016) | 45 (466/1,035) |
| End of treatment response | 53 (542/1,019) | 49 (500/1,016) | 64 (667/1,035) |
| Relapse | 24 (123/523) | 20 (95/475) | 32 (193/612) |
| SVR | 40 (406/1,019) | 38 (386/1,016) | 41 (423/1,035) |
| SVR in patients with undetectable HCV-RNA at treatment week 12 | 81 (328/407) | 83 (303/366) | 74 (344/466) |
* (HCV-RNA PCR assay, with a lower limit of quantitation of 27 IU/ml)
Lack of early virologic response by Treatment week 12 (detectable HCV-RNA with a < 2 log10 reduction from baseline) was a criterion for discontinuation of treatment.
In all three treatment groups, sustained virologic response rates were similar. In patients of African American origin (which is known to be a poor prognostic factor for HCV eradication), treatment with Intron A Peg (1.5 µg/kg)/ribavirin combination therapy resulted in a higher sustained virologic response rate compared to Intron A Peg 1 µg/kg dose. At the Intron A Peg 1.5 µg/kg plus ribavirin dose, sustained virologic response rates were lower in patients with cirrhosis, in patients with normal ALT levels, in patients with a baseline viral load > 600,000 IU/ml, and in patients > 40 years old. Caucasian patients had a higher sustained virologic response rate compared to the African Americans. Among patients with undetectable HCV-RNA at the end of treatment, the relapse rate was 24 %.
Predictability of sustained virological response - Naïve patients: Virological response by week 12 is defined as at least 2-log viral load decrease or undetectable levels of HCV-RNA.Virological response by week 4 is defined as at least 1-log viral load decrease or undetectable levels of HCV-RNA. These time points (treatment week 4 and treatment week 12) have been shown to be predictive for sustained response (Table 12).
Table 12 Predictive value of in-treatment Virologic Response while on Intron A Peg 1.5 µg/kg/ribavirin 800-1,400 mg combination therapy
| Negative | Positive | ||||||
| No response at treatment week | No sustained response | Negative predictive value | Response at treatment week | Sustained response | Positive predictive value | ||
| Genotype 1* | |||||||
| By week 4*** (n=950) | |||||||
| HCV-RNA negative | 834 | 539 | 65 % (539/834) | 116 | 107 | 92 % (107/116) | |
| HCV-RNA negative or > 1 log decrease in viral load | 220 | 210 | 95 % (210/220) | 730 | 392 | 54 % (392/730) | |
| By week 12*** (n=915) | |||||||
| HCV-RNA negative | 508 | 433 | 85 % (433/508) | 407 | 328 | 81 % (328/407) | |
| HCV-RNA negative or > 2 log decrease in viral load | 206 | 205 | N/A†| 709 | 402 | 57 % (402/709) | |
| Genotype 2, 3** | |||||||
| By week 12 (n= 215) | |||||||
| HCV-RNA negative or > 2 log decrease in viral load | 2 | 1 | 50 % (1/2) | 213 | 177 | 83 % (177/213) | |
*Genotype 1 receive 48 weeks treatment
**Genotype 2, 3 receive 24 weeks treatment
***The presented results are from a single point of time. A patient may be missing or have had a different result for week 4 or week 12.
†These criteria were used in the protocol: If week 12 HCV-RNA is positive and < 2log10 decrease from baseline, patients to stop therapy. If week 12 HCV-RNA is positive and decreased > 2log10 from baseline, then retest HCV-RNA at week 24 and if positive, patients to stop therapy.
The negative predictive value for sustained response in patients treated with Intron A Peg in monotherapy was 98 %.
HCV/HIV Co-infected patients
Two trials have been conducted in patients co-infected with HIV and HCV. The response to treatment in both of these trials is presented in Table 13. Study 1 (RIBAVIC; P01017) was a randomized, multicentre study which enrolled 412 previously untreated adult patients with chronic hepatitis C who were co-infected with HIV. Patients were randomized to receive either Intron A Peg (1.5 µg/kg/week) plus ribavirin (800 mg/day) or interferon alfa-2b (3 MIU TIW) plus ribavirin (800 mg/day) for 48 weeks with a follow-up period of 6 months. Study 2 (P02080) was a randomized, single centre study that enrolled 95 previously untreated adult patients with chronic hepatitis C who were co-infected with HIV. Patients were randomized to receive either Intron A Peg (100 or 150 µg/week based on weight) plus ribavirin (800-1,200 mg/day based on weight) or interferon alfa-2b (3 MIU TIW) plus ribavirin (800-1,200 mg/day based on weight). The duration of therapy was 48 weeks with a follow-up period of 6 months except for patients infected with genotypes 2 or 3 and viral load < 800,000 IU/ml (Amplicor) who were treated for 24 weeks with a 6-month follow-up period.
Table 13 Sustained virological response based on genotype after Intron A Peg in combination with Ribavirin in HCV/HIV Co-infected patients
| Study 11 | Study 22 | |||||
| Intron A Peg (1.5 µg/kg/ week) + ribavirin (800 mg) | Interferon alfa-2b (3 MIU TIW) + ribavirin (800 mg) | p valuea | Intron A Peg (100 or 150c µg/week) + ribavirin (800- 1,200 mg)d | Interferon alfa-2b (3 MIU TIW) + ribavirin (800- 1,200 mg)d | p valueb | |
| All | 27 % (56/205) | 20 % (41/205) | 0.047 | 44 % (23/52) | 21 % (9/43) | 0.017 |
| Genotype 1, 4 | 17 % (21/125) | 6 % (8/129) | 0.006 | 38 % (12/32) | 7 % (2/27) | 0.007 |
| Genotype 2, 3 | 44 % (35/80) | 43 % (33/76) | 0.88 | 53 % (10/19) | 47 % (7/15) | 0.730 |
| MIU = million international units; TIW = three times a week. a: p value based on Cochran-Mantel Haenszel Chi square test. b: p value based on chi-square test. c: subjects < 75 kg received 100 µg/week Intron A Peg and subjects > 75 kg received 150 µg/week Intron A Peg. d: ribavirin dosing was 800 mg for patients < 60 kg, 1,000 mg for patients 60-75 kg, and 1,200 mg for patients > 75 kg. 1Carrat F, Bani-Sadr F, Pol S et al. JAMA 2004; 292(23): 2839-2848. 2 Laguno M, Murillas J, Blanco J.L et al. AIDS 2004; 18(13): F27-F36. | ||||||
Histological response: Liver biopsies were obtained before and after treatment in Study 1 and were available for 210 of the 412 subjects (51 %). Both the Metavir score and Ishak grade decreased among subjects treated with Intron A Peg in combination with ribavirin. This decline was significant among responders (-0.3 for Metavir and -1.2 for Ishak) and stable (-0.1 for Metavir and -0.2 for Ishak) among non-responders. In terms of activity, about one-third of sustained responders showed improvement and none showed worsening. There was no improvement in terms of fibrosis observed in this study. Steatosis was significantly improved in patients infected with HCV Genotype 3.
Intron A Peg/ribavirin retreatment of prior treatment failures
In a non-comparative trial, 2,293 patients with moderate to severe fibrosis who failed previous treatment with combination alpha interferon/ribavirin were retreated with Intron A Peg, 1.5 micrograms/kg subcutaneously, once weekly, in combination with weight adjusted ribavirin. Failure to prior therapy was defined as relapse or non-response (HCV-RNA positive at the end of a minimum of 12 weeks of treatment).
Patients who were HCV-RNA negative at treatment week 12 continued treatment for 48 weeks and were followed for 24 weeks post-treatment. Response week 12 was defined as undetectable HCV-RNA after 12 weeks of treatment. Sustained Virologic Response (SVR) is defined as undetectable HCV-RNA at 24 weeks post-treatment (Table 14).
Table 14 Rates of response to retreatment in prior treatment failures
| Patients with undetectable HCV-RNA at treatment week 12 and SVR upon retreatment | |||||
|
interferon alpha/ribavirin |
peginterferon alpha/ribavirin | Overall population* | |||
| Response week 12 % (n/N) | SVR % (n/N) 99% CI | Response week 12 % (n/N) | SVR % (n/N) 99% CI | SVR % (n/N) 99 % CI | |
| Overall | 38.6 (549/1,423) | 59.4 (326/549) 54.0,64.8 | 31.5 (272/863) | 50.4 (137/272) 42.6, 58.2 | 21.7 (497/2,293) 19.5, 23.9 |
| Prior response | |||||
Intron A Peg is a well characterized polyethylene glycol-modified (“pegylatedâ€) derivative of interferon alfa-2b and is predominantly composed of monopegylated species. The plasma half-life of Intron A Peg is prolonged compared with nonpegylated interferon alfa-2b. Intron A Peg has a potential to depegylate to free interferon alfa-2b. The biologic activity of the pegylated isomers is qualitatively similar, but weaker than free interferon alfa-2b.
Following subcutaneous administration, maximal serum concentrations occur between 15-44 hours post-dose, and are sustained for up to 48-72 hours post-dose.
Intron A Peg Cmax and AUC measurements increase in a dose-related manner. Mean apparent volume of distribution is 0.99 l/kg.
Upon multiple dosing, there is an accumulation of immunoreactive interferons. There is, however, only a modest increase in biologic activity as measured by a bioassay.
Mean (SD) Intron A Peg elimination half-life is approximately 40 hours (13.3 hours), with apparent clearance of 22.0 ml/hr/kg. The mechanisms involved in clearance of interferons in man have not yet been fully elucidated. However, renal elimination may account for a minority (approximately 30 %) of Intron A Peg apparent clearance.
Renal impairment
Renal clearance appears to account for 30 % of total clearance of Intron A Peg. In a single dose study (1.0 microgram/kg) in patients with impaired renal function, Cmax, AUC, and half-life increased in relation to the degree of renal impairment.
Following multiple dosing of Intron A Peg (1.0 microgram/kg subcutaneously administered every week for four weeks) the clearance of Intron A Peg is reduced by a mean of 17 % in patients with moderate renal impairment (creatinine clearance 30-49 ml/minute) and by a mean of 44 % in patients with severe renal impairment (creatinine clearance 15-29 ml/minute) compared to subjects with normal renal function. Based on single dose data, clearance was similar in patients with severe renal impairment not on dialysis and in patients who were receiving hemodialysis. The dose of Intron A Peg for monotherapy should be reduced in patients with moderate or severe renal impairment. Patients with creatinine clearance < 50 ml/minute must not be treated with Intron A Peg in combination with ribavirin (bitherapy or tritherapy).
Because of marked inter-subject variability in interferon pharmacokinetics, it is recommended that patients with severe renal impairment be closely monitored during treatment with Intron A Peg
Hepatic impairment
The pharmacokinetics of Intron A Peg have not been evaluated in patients with severe hepatic dysfunction.
Elderly (> 65 years of age)
The pharmacokinetics of Intron A Peg following a single subcutaneous dose of 1.0 microgram/kg were not affected by age. The data suggest that no alteration in Intron A Peg dosage is necessary based on advancing age.
Paediatric population
Multiple-dose pharmacokinetic properties for Intron A Peg and ribavirin (capsules and oral solution) in children and adolescent patients with chronic hepatitis C have been evaluated during a clinical study. In children and adolescent patients receiving body surface area-adjusted dosing of Intron A Peg at 60 μg/m2/week, the log transformed ratio estimate of exposure during the dosing interval is predicted to be 58 % (90 % CI: 141-177 %) higher than observed in adults receiving 1.5 μg/kg/week.
Interferon neutralising factors
Interferon neutralising factor assays were performed on serum samples of patients who received Intron A Peg in the clinical trial. Interferon neutralising factors are antibodies which neutralise the antiviral activity of interferon. The clinical incidence of neutralising factors in patients who received Intron A Peg 0.5 micrograms/kg is 1.1 %.
Transfer into seminal fluid
Seminal transfer of ribavirin has been studied. Ribavirin concentration in seminal fluid is approximately two-fold higher compared to serum. However, ribavirin systemic exposure of a female partner after sexual intercourse with a treated patient has been estimated and remains extremely limited compared to therapeutic plasma concentration of ribavirin.
| Psychiatric and Central Nervous System (CNS) Severe CNS effects, particularly depression, suicidal ideation and attempted suicide have been observed in some patients during Intron A Peg therapy, and even after treatment discontinuation mainly during the 6-month follow-up period. Other CNS effects including aggressive behaviour (sometimes directed against others such as homicidal ideation), bipolar disorders, mania, confusion and alterations of mental status have been observed with alpha interferons. Patients should be closely monitored for any signs or symptoms of psychiatric disorders. If such symptoms appear, the potential seriousness of these undesirable effects must be borne in mind by the prescribing physician and the need for adequate therapeutic management should be considered. If psychiatric symptoms persist or worsen, or suicidal or homicidal ideation is identified, it is recommended that treatment with Intron A Peg be discontinued, and the patient followed, with psychiatric intervention as appropriate. Patients with existence of, or history of severe psychiatric conditions If treatment with peginterferon alfa-2b is judged necessary in adult patients with existence or history of severe psychiatric conditions, this should only be initiated after having ensured appropriate individualised diagnostic and therapeutic management of the psychiatric condition. - The use of Intron A Peg in children and adolescents with existence of or history of severe psychiatric conditions is contraindicated. Among children and adolescents treated with interferon alfa-2b in combination with ribavirin, suicidal ideation or attempts were reported more frequently compared to adult patients (2.4 % vs 1 %) during treatment and during the 6-month follow-up after treatment. As in adult patients, children and adolescents experienced other psychiatric adverse events (e.g. depression, emotional lability, and somnolence). Patients with substance use/abuse HCV infected patients having a co-occurring substance use disorder (alcohol, cannabis, etc) are at an increased risk of developing psychiatric disorders or exacerbation of already existing psychiatric disorders when treated with alpha interferon. If treatment with alpha interferon is judged necessary in these patients, the presence of psychiatric co-morbidities and the potential for other substance use should be carefully assessed and adequately managed before initiating therapy. If necessary, an inter-disciplinary approach including a mental health care provider or addiction specialist should be considered to evaluate, treat and follow the patient. Patients should be closely monitored during therapy and even after treatment discontinuation. Early intervention for re-emergence or development of psychiatric disorders and substance use is recommended. Growth and development (children and adolescents) During the course of therapy lasting up to 48 weeks in patients ages 3 through 17 years, weight loss and growth inhibition were common. Long-term data available in children treated with the combination therapy of pegylated interferon/ribavirin are indicative of substantial growth retardation. Thirty two percent (30/94) of subjects demonstrated > 15 percentile decrease in height-for-age percentile 5 years after completion of therapy. Case by case benefit/risk assessment in children The expected benefit of treatment should be carefully weighed against the safety findings observed for children and adolescents in the clinical trials. - It is important to consider that the combination therapy induced a growth inhibition, that resulted in reduced height in some patients. - This risk should be weighed against the disease characteristics of the child, such as evidence of disease progression (notably fibrosis), co-morbidities that may negatively influence the disease progression (such as HIV co-infection), as well as prognostic factors of response (HCV genotype and viral load). Whenever possible the child should be treated after the pubertal growth spurt, in order to reduce the risk of growth inhibition. Although data are limited, no evidence of long-term effects on sexual maturation was noted in the 5-year observational follow-up study. |
More significant obtundation and coma, including cases of encephalopathy, have been observed in some patients, usually elderly, treated at higher doses for oncology indications. While these effects are generally reversible, in a few patients full resolution took up to three weeks. Very rarely, seizures have occurred with high doses of interferon alpha.
All patients in the selected chronic hepatitis C studies had a liver biopsy before inclusion, but in certain cases (i.e. patients with genotype 2 and 3), treatment may be possible without histological confirmation. Current treatment guidelines should be consulted as to whether a liver biopsy is needed prior to commencing treatment.
Acute hypersensitivity
Acute hypersensitivity reactions (e.g., urticaria, angioedema, bronchoconstriction, anaphylaxis) have been observed rarely during interferon alfa-2b therapy. If such a reaction develops during treatment with Intron A Peg, discontinue treatment and institute appropriate medical therapy immediately. Transient rashes do not necessitate interruption of treatment.
Cardiovascular system
As with interferon alfa-2b, adult patients with a history of congestive heart failure, myocardial infarction and/or previous or current arrhythmic disorders, receiving Intron A Peg therapy require close monitoring. It is recommended that patients who have pre-existing cardiac abnormalities have electrocardiograms taken prior to and during the course of treatment. Cardiac arrhythmias (primarily supraventricular) usually respond to conventional therapy but may require discontinuation of Intron A Peg therapy. There are no data in children or adolescents with a history of cardiac disease.
Hepatic Failure
Intron A Peg increases the risk of hepatic decompensation and death in patients with cirrhosis. As with all interferons, discontinue treatment with Intron A Peg in patients who develop prolongation of coagulation markers which might indicate liver decompensation. Liver enzymes and hepatic function should be closely monitored in cirrhotic patients.
Pyrexia
While pyrexia may be associated with the flu-like syndrome reported commonly during interferon therapy, other causes of persistent pyrexia must be ruled out.
Hydration
Adequate hydration must be maintained in patients undergoing Intron A Peg therapy since hypotension related to fluid depletion has been seen in some patients treated with alpha interferons. Fluid replacement may be necessary.
Pulmonary changes
Pulmonary infiltrates, pneumonitis, and pneumonia, occasionally resulting in fatality, have been observed rarely in interferon alpha treated patients. Any patient developing pyrexia, cough, dyspnea or other respiratory symptoms must have a chest X-ray taken. If the chest X-ray shows pulmonary infiltrates or there is evidence of pulmonary function impairment, the patient is to be monitored closely, and, if appropriate, discontinue interferon alpha. Prompt discontinuation of interferon alpha administration and treatment with corticosteroids appear to be associated with resolution of pulmonary adverse events.
Autoimmune disease
The development of auto-antibodies and autoimmune disorders has been reported during treatment with alpha interferons.8).
Cases of Vogt-Koyanagi-Harada (VKH) syndrome have been reported in patients with chronic hepatitis C treated with interferon. This syndrome is a granulomatous inflammatory disorder affecting the eyes, auditory system, meninges, and skin. If VKH syndrome is suspected, antiviral treatment should be withdrawn and corticosteroid therapy discussed.
Ocular changes
Ophthalmologic disorders, including retinal haemorrhages, retinal exudates, serous retinal detachment, and retinal artery or vein occlusion have been reported in rare instances after treatment with alpha interferons. All patients should have a baseline eye examination. Any patient complaining of ocular symptoms, including loss of visual acuity or visual field must have a prompt and complete eye examination. Periodic visual examinations are recommended during Intron A Peg therapy, particularly in patients with disorders that may be associated with retinopathy, such as diabetes mellitus or hypertension. Discontinuation of Intron A Peg should be considered in patients who develop new or worsening ophthalmological disorders.
Thyroid changes
Infrequently, adult patients treated for chronic hepatitis C with interferon alpha have developed thyroid abnormalities, either hypothyroidism or hyperthyroidism. Approximately 21 % of children treated with Intron A Peg/ribavirin combination therapy developed increase in thyroid stimulating hormone (TSH). Another approximately 2 % had a transient decrease below the lower limit of normal. Prior to initiation of Intron A Peg therapy, TSH levels must be evaluated and any thyroid abnormality detected at that time must be treated with conventional therapy. Determine TSH levels if, during the course of therapy, a patient develops symptoms consistent with possible thyroid dysfunction. In the presence of thyroid dysfunction, Intron A Peg treatment may be continued if TSH levels can be maintained in the normal range by medicine. Children and adolescents should be monitored every 3 months for evidence of thyroid dysfunction (e.g. TSH).
Metabolic disturbances
Hypertriglyceridemia and aggravation of hypertriglyceridemia, sometimes severe, have been observed. Monitoring of lipid levels is, therefore, recommended.
HCV/HIV Co-infection
Mitochondrial toxicity and lactic acidosis
Patients co-infected with HIV and receiving Highly Active Anti-Retroviral Therapy (HAART) may be at increased risk of developing lactic acidosis. Caution should be used when adding Intron A Peg and ribavirin to HAART therapy (see ribavirin SmPC).
Hepatic decompensation in HCV/HIV co-infected patients with advanced cirrhosis
Co-infected patients with advanced cirrhosis receiving HAART may be at increased risk of hepatic decompensation and death. Adding treatment with alfa interferons alone or in combination with ribavirin may increase the risk in this patient subset. Other baseline factors in co-infected patients that may be associated with a higher risk of hepatic decompensation include treatment with didanosine and elevated bilirubin serum concentration.
Co-infected patients receiving both antiretroviral (ARV) and anti-hepatitis treatment should be closely monitored, assessing their Child-Pugh score during treatment. Patients progressing to hepatic decompensation should have their anti-hepatitis treatment immediately discontinued and the ARV treatment reassessed.
Haematological abnormalities in HCV/HIV co-infected patients
Patients treated with Intron A Peg and ribavirin combination therapy and zidovudine are at increased risk of developing anaemia and therefore the concomitant use of this combination with zidovudine is not recommended.
Patients with low CD4 counts
In patients co-infected with HCV/HIV, limited efficacy and safety data (N = 25) are available in subjects with CD4 counts less than 200 cells/µl. Caution is therefore warranted in the treatment of patients with low CD4 counts.
Please refer to the respective SmPCs of the antiretroviral medicinal products that are to be taken concurrently with HCV therapy for awareness and management of toxicities specific for each product and the potential for overlapping toxicities with Intron A Peg and ribavirin.
HCV/HBV Coinfection
Cases of hepatitis B re-activation (some with severe consequences) have been reported in patients co-infected with hepatitis B and C viruses treated with interferon. The frequency of such re-activation appears to be low.
All patients should be screened for hepatitis B before starting treatment with interferon for hepatitis C; patients co-infected with hepatitis B and C must then be monitored and managed according to current clinical guidelines.
Dental and periodontal disorders
Dental and periodontal disorders, which may lead to loss of teeth, have been reported in patients receiving Intron A Peg and ribavirin combination therapy. In addition, dry mouth could have a damaging effect on teeth and mucous membranes of the mouth during long-term treatment with the combination of Intron A Peg and ribavirin. Patients should brush their teeth thoroughly twice daily and have regular dental examinations. In addition some patients may experience vomiting. If this reaction occurs, they should be advised to rinse out their mouth thoroughly afterwards.
Organ transplant recipients
The safety and efficacy of Intron A Peg alone or in combination with ribavirin for the treatment of hepatitis C in liver or other organ transplant recipients have not been studied. Preliminary data indicate that interferon alpha therapy may be associated with an increased rate of kidney graft rejection. Liver graft rejection has also been reported.
Other
Due to reports of interferon alpha exacerbating pre-existing psoriatic disease and sarcoidosis, use of Intron A Peg in patients with psoriasis or sarcoidosis is recommended only if the potential benefit justifies the potential risk.
Laboratory tests
Standard haematologic tests, blood chemistry and a test of thyroid function must be conducted in all patients prior to initiating therapy. Acceptable baseline values that may be considered as a guideline prior to initiation of Intron A Peg therapy are:
| - Platelets - Neutrophil count - TSH level | > 100,000/mm3 > 1,500/mm3 must be within normal limits |
Laboratory evaluations are to be conducted at weeks 2 and 4 of therapy, and periodically thereafter as clinically appropriate. HCV-RNA should be measured periodically during treatment.
Long term maintenance monotherapy
It has been demonstrated in a clinical study that peginterferon alfa-2b at low-dose (0.5 μg/kg/week) is not effective in long term maintenance monotherapy (for a mean duration of 2.5 years) for the prevention of disease progression in non responders with compensated cirrhosis. No statistically significant effect on the time to development of the first clinical event (liver decompensation, hepatocellular carcinoma, death and/or liver transplantation) was observed as compared to the absence of treatment. Intron A Peg should therefore not be used as long term maintenance monotherapy.
Important information about some of the ingredients of Intron A Peg
Patients with rare hereditary problems of fructose intolerance, glucose galactose malabsorption or sucrase-isomaltase insufficiency should not take this medicine.
This medicinal product contains less than 1 mmol sodium (23 mg) per 0.7 ml, i.e., essentially "sodium-free".
Patients who develop fatigue, somnolence or confusion during treatment with Intron A Peg are cautioned to avoid driving or operating machines.
Treatment should be initiated and monitored only by a physician experienced in the management of patients with hepatitis C.
Posology
Intron A Peg should be administered as a once weekly subcutaneous injection. The dose administered in adults depends on whether it is used in combination therapy (bitherapy or tritherapy) or as monotherapy.
Intron A Peg combination therapy (bitherapy or tritherapy)
Bitherapy (Intron A Peg with ribavirin): applies to all adult and paediatric patients 3 years of age and older.
Tritherapy (Intron A Peg with ribavirin and boceprevir): applies to adult patients with genotype 1 CHC.
Adults - Dose to be administered
Intron A Peg 1.5 micrograms/kg/week in combination with ribavirin capsules.
The intended dose of 1.5 μg/kg of Intron A Peg to be used in combination with ribavirin may be delivered in weight categories with the Intron A Peg strengths according to Table 1. Ribavirin capsules are to be administered orally each day in two divided doses with food (morning and evening).
Table 1 Dosing for combination therapy*
| Body weight (kg) | Intron A Peg | Ribavirin capsules | ||
| Intron A Peg strength (μg/0.5 ml) | Administer once weekly (ml) | Total daily ribavirin dose (mg) | Number of capsules (200 mg) | |
| < 40 | 50 | 0.5 | 800 | 4a |
| 40-50 | 80 | 0.4 | 800 | 4a |
| 51-64 | 80 | 0.5 | 800 | 4a |
| 65-75 | 100 | 0.5 | 1,000 | 5b |
| 76-80 | 120 | 0.5 | 1,000 | 5b |
| 81-85 | 120 | 0.5 | 1,200 | 6c |
| 86-105 | 150 | 0.5 | 1,200 | 6c |
| > 105 | 150 | 0.5 | 1,400 | 7d |
a: 2 morning, 2 evening
b: 2 morning, 3 evening
c: 3 morning, 3 evening
d: 3 morning, 4 evening
* Refer to the SmPC of boceprevir for details about the dose of boceprevir to be administered in tritherapy.
Adults - Duration of treatment - Naïve patients
Tritherapy: Refer to the SmPC for boceprevir.
- Genotype 1:
- Patients who have undetectable HCV-RNA at treatment week 12, treatment should be continued for another nine month period (i.e., a total of 48 weeks).
- Patients with detectable but > 2 log decrease in HCV-RNA level from baseline at treatment week 12 should be reassessed at treatment week 24 and, if HCV-RNA is undetectable, they should continue with full course of therapy (i.e. a total of 48 weeks). However, if HCV-RNA is still detectable at treatment week 24, discontinuation of therapy should be considered.
- In the subset of patients with genotype 1 infection and low viral load (< 600,000 IU/ml) who become HCV-RNA negative at treatment week 4 and remain HCV-RNA negative at week 24, the treatment could either be stopped after this 24 week treatment course or pursued for an additional 24 weeks (i.e. overall 48 weeks treatment duration). However, an overall 24 weeks treatment duration may be associated with a higher risk of relapse than a 48 weeks treatment duration.
- Genotypes 2 or 3:
It is recommended that all patients be treated with bitherapy for 24 weeks, except for HCV/HIV co-infected patients who should receive 48 weeks of treatment.
- Genotype 4:
In general, patients infected with genotype 4 are considered harder to treat and limited study data (n=66) indicate they are compatible with a duration of treatment with bitherapy as for genotype 1.
Adults - Duration of treatment - HCV/HIV co-infection
Bitherapy: The recommended duration of treatment for HCV/HIV co-infected patients is 48 weeks with bitherapy, regardless of genotype.
Predictability of response and non-response in HCV/HIV co-infection - Early virological response by week 12, defined as a 2 log viral load decrease or undetectable levels of HCV-RNA, has been shown to be predictive for sustained response. The negative predictive value for sustained response in HCV/HIV co-infected patients treated with Intron A Peg in combination with ribavirin was 99 % (67/68; Study 1). A positive predictive value of 50 % (52/104; Study 1) was observed for HCV/HIV co-infected patients receiving bitherapy.
Adults - Duration of treatment - Retreatment
Tritherapy: Refer to the SmPC for boceprevir.
Bitherapy: Predictability of sustained virological response - All patients, irrespective of genotype, who have demonstrated serum HCV-RNA below the limits of detection at week 12 should receive 48 weeks of bitherapy.).
Retreatment duration greater than 48 weeks in non-responder patients with genotype 1 has not been studied with pegylated interferon alfa-2b and ribavirin combination therapy.
Paediatric population (bitherapy only) - Dose to be administered
Dosing for children 3 years of age and older and adolescent patients is determined by body surface area for Intron A Peg and by body weight for ribavirin. The recommended dose of Intron A Peg is 60 μg/m2/week subcutaneously in combination with ribavirin 15 mg/kg/day orally in two divided doses with food (morning and evening).
Paediatric population (bitherapy only) - Duration of treatment
- Genotype 1:
The recommended duration of treatment with bitherapy is 1 year. By extrapolation from clinical data on combination therapy with standard interferon in paediatric patients (negative predictive value 96 % for interferon alfa-2b/ribavirin), patients who fail to achieve virological response at 12 weeks are highly unlikely to become sustained virological responders. Therefore, it is recommended that children and adolescent patients receiving Intron A Peg/ribavirin combination be discontinued from therapy if their week 12 HCV-RNA dropped < 2 log10 compared to pretreatment or if they have detectable HCV-RNA at treatment week 24.
- Genotype 2 or 3:
The recommended duration of treatment with bitherapy is 24 weeks.
- Genotype 4:
Only 5 children and adolescents with Genotype 4 were treated in the Intron A Peg/ribavirin clinical trial. The recommended duration of treatment with bitherapy is 1 year. It is recommended that children and adolescent patients receiving Intron A Peg/ribavirin combination be discontinued from therapy if their week 12 HCV-RNA dropped < 2 log10 compared to pretreatment or if they have detectable HCV-RNA at treatment week 24.
Intron A Peg monotherapy - Adults
Dose to be administered
As monotherapy the Intron A Peg regimen is 0.5 or 1.0 μg/kg/week. The lowest Intron A Peg strength available is 50 μg/0.5 ml; therefore for patients prescribed 0.5 μg/kg/week, doses must be adjusted by volume as shown in Table 2. For the 1.0 μg/kg dose, similar volume adjustments can be made or alternate strengths can be used as shown in Table 2. Intron A Peg monotherapy was not studied in HCV/HIV co-infected patients.
Table 2 Monotherapy dosing
|
| 0.5 μg/kg | 1.0 μg/kg | ||
| Body weight (kg) | Intron A Peg strength (μg/0.5 ml) | Administer once weekly (ml) | Intron A Peg strength (μg/0.5 ml) | Administer once weekly (ml) |
| 30-35 | 50* | 0.15 | 80 | 0.2 |
| 36-45 | 50 | 0.2 | 50 | 0.4 |
| 46-56 | 50 | 0.25 | 50 | 0.5 |
| 57-72 | 80 | 0.2 | 80 | 0.4 |
| 73-88 | 50 | 0.4 | 80 | 0.5 |
| 89-106 | 50 | 0.5 | 100 | 0.5 |
| 107-120** | 80 | 0.4 | 120 | 0.5 |
Minimum delivery for pen is 0.2 ml.
* Must use vial.
** For patients > 120 kg, the Intron A Peg dose should be calculated based on the individual patient weight. This may require combinations of various Intron A Peg dose strengths and volumes.
Duration of treatment
For patients who exhibit virological response at week 12, treatment should be continued for at least another three-month period (i.e., a total of six months). The decision to extend therapy to one year of treatment should be based on prognostic factors (e.g., genotype, age > 40 years, male gender, bridging fibrosis).
Dose modification for all patients (monotherapy and combination therapy)
If severe adverse reactions or laboratory abnormalities develop during treatment with Intron A Peg monotherapy or combination therapy, the dosages of Intron A Peg and/or ribavirin must be modified as appropriate, until the adverse reactions abate. Dose reduction of boceprevir is not recommended. Boceprevir must not be administered in the absence of Intron A Peg and ribavirin.
As adherence might be of importance for outcome of therapy, the dose of Intron A Peg and ribavirin should be kept as close as possible to the recommended standard dose. Guidelines were developed in clinical trials for dose modification.
Combination therapy dose reduction guidelines
Table 2a Dose modification guidelines for combination therapy based on laboratory parameters
| Laboratory values | Reduce only ribavirin daily dose (see note 1) if: | Reduce only Intron A Peg dose (see note 2) if: | Discontinue combination therapy if: |
| Haemoglobin | > 8.5 g/dl, and < 10 g/dl | - | < 8.5 g/dl |
| Adults: Haemoglobin in Patients with history of stable cardiac disease Children and adolescents: not applicable |
> 2 g/dl decrease in haemoglobin during any four week period during treatment (permanent dose reduction) |
< 12 g/dl after four weeks of dose reduction | |
| Leukocytes | - | > 1.0 x 109/l, and < 1.5 x 109/l l | < 1.0 x 109/l |
| Neutrophils | - | > 0.5 x 109/l, and < 0.75 x 109/l | < 0.5 x 109/l |
| Platelets | - | > 25 x 109/l, and < 50 x 109/l (adults) > 50 x 109/l, and <70 x 109/l (children and adolescents) | < 25 x 109/l (adults) < 50 x 109/l (children and adolescents) |
| Bilirubin - direct | - | - | 2.5 x ULN* |
| Bilirubin - indirect | > 5 mg/dl | - | > 4 mg/dl (for > 4 weeks) |
| Serum Creatinine | - | - | > 2.0 mg/dl |
| Creatinine Clearance | - | - | Discontinue ribavirin if CrCL < 50ml/min |
| Alanine aminotransferase (ALT) or Aspartate aminotransferase (AST) | - | - | 2 x baseline and > 10 x ULN*
2 x baseline and > 10 x ULN* |
* Upper limit of normal
Note 1: In adult patients 1st dose reduction of ribavirin is by 200 mg/day (except in patients receiving the 1,400 mg, dose reduction should be by 400 mg/day). If needed, 2nd dose reduction of ribavirin is by an additional 200 mg/day. Patients whose dose of ribavirin is reduced to 600 mg daily receive one 200 mg capsule in the morning and two 200 mg capsules in the evening.
In children and adolescent patients 1st dose reduction of ribavirin is to 12 mg/kg/day, 2nd dose reduction of ribavirin is to 8 mg/kg/day.
Note 2: In adult patients 1st dose reduction of Intron A Peg is to 1 µg/kg/week. If needed, 2nd dose reduction of Intron A Peg is to 0.5 µg/kg/week. For patients on Intron A Peg monotherapy: refer to monotherapy dose reduction guidelines section for dose reduction.
In children and adolescent patients 1st dose reduction of Intron A Peg is to 40 μg/m2/week, 2nd dose reduction of Intron A Peg is to 20 μg/m2/week.
Dose reduction of Intron A Peg in adults may be accomplished by reducing the prescribed volume or by utilizing a lower dose strength as shown in Table 2b. Dose reduction of Intron A Peg in children and adolescents is accomplished by modifying the recommended dose in a two-step process from the original starting dose of 60 μg/m2/week, to 40 μg/m2/week, then to 20 μg/m2/week, if needed.
Table 2b Two-step dose reduction of Intron A Peg in combination therapy in adults
| First dose reduction to Intron A Peg 1 µg/kg | Second dose reduction to Intron A Peg 0.5 µg/kg | ||||||
| Body weight (kg)
| Intron A Peg strength (µg/0.5 ml) | Amount of Intron A Peg to administer (µg) | Volume of Intron A Peg to administer (ml) | Body weight (kg) | Intron A Peg strength (µg/0.5 ml) | Amount of Intron A Peg to administer (µg) | Volume of Intron A Peg to administer (ml) |
| < 40 | 50 | 35 | 0.35 | < 40 | 50 | 20 | 0.2 |
| 40 - 50 | 120 | 48 |
0.2 | 40 - 50 | 50 | 25 | 0.25 |
| 51 - 64 | 80 | 56 | 0.35 | 51 - 64 | 80 | 32 | 0.2 |
| 65 - 75 | 100 | 70 | 0.35 | 65 - 75 | 50 | 35 | 0.35 |
| 76 - 85 | 80 | 80 | 0.5 | 76 - 85 | 120 | 48 | 0.2 |
| 86 - 105 | 120 | 96 | 0.4 | 86 - 105 | 50 | 50 | 0.5 |
| > 105 | 150 | 105 | 0.35 | > 105 | 80 | 64 | 0.4 |
Intron A Peg monotherapy dose reduction guidelines in adults
Dose modification guidelines for adult patients who use Intron A Peg monotherapy are shown in Table 3a.
Table 3a Dose modification guidelines for Intron A Peg monotherapy in adults based on laboratory parameters
| Laboratory values | Reduce Intron A Peg to one-half dose if: | Discontinue Intron A Peg if: |
| Neutrophils | > 0.5 x 109/l, and < 0.75 x 109/l | < 0.5 x 109/l |
| Platelets | > 25 x 109/l, and < 50 x 109/l | < 25 x 109/l |
For adult patients who use 0.5 μg/kg Intron A Peg monotherapy, dose reduction may be accomplished by reducing the prescribed volume by one-half as shown in Table 3b.
Table 3b Reduced Intron A Peg dose (0.25 μg/kg) for the 0.5 μg/kg monotherapy regimen in adults
| Body weight (kg) | Intron A Peg strength (μg/0.5 ml) | Amount of Intron A Peg to administer (μg) | Volume of Intron A Peg to administer (ml) |
| 30-35 | 50* | 8 | 0.08 |
| 36-45 | 50* | 10 | 0.1 |
| 46-56 | 50* | 13 | 0.13 |
| 57-72 | 80* | 16 | 0.1 |
| 73-88 | 50 | 20 | 0.2 |
| 89-106 | 50 | 25 | 0.25 |
| 107-120** | 80 | 32 | 0.2 |
Minimum delivery for pen is 0.2 ml.
* Must use vial.
** For patients > 120 kg, the Intron A Peg dose should be calculated based on the individual patient weight. This may require combinations of various Intron A Peg dose strengths and volumes.
For adult patients who use 1.0 μg/kg Intron A Peg monotherapy, dose reduction may be accomplished by reducing the prescribed volume by one-half or by utilizing a lower dose strength as shown in Table 3c.
Table 3c Reduced Intron A Peg dose (0.5 μg/kg) for the 1.0 μg/kg monotherapy regimen in adults
| Body weight (kg) | Intron A Peg strength (μg/0.5 ml) | Amount of Intron A Peg to administer (μg) | Volume of Intron A Peg to administer (ml) |
| 30-35 | 50* | 15 | 0.15 |
| 36-45 | 50 | 20 | 0.20 |
| 46-56 | 50 | 25 | 0.25 |
| 57-72 | 80 | 32 | 0.2 |
| 73-88 | 50 | 40 | 0.4 |
| 89-106 | 50 | 50 | 0.5 |
| 107-120** | 80 | 64 | 0.4 |
Minimum delivery for pen is 0.2 ml.
* Must use vial.
** For patients > 120 kg, the Intron A Peg dose should be calculated based on the individual patient weight. This may require combinations of various Intron A Peg dose strengths and volumes.
Special populations
Renal impairment
Monotherapy
Intron A Peg should be used with caution in patients with moderate to severe renal impairment. In patients with moderate renal dysfunction (creatinine clearance 30-50 ml/minute), the starting dose of Intron A Peg should be reduced by 25 %. Patients with severe renal dysfunction (creatinine clearance 15-29 ml/minute) should have the starting dose of Intron A Peg reduced by 50 %. Data are not available for the use of Intron A Peg in patients with creatinine clearance < 15 ml/minute. Patients with severe renal impairment, including those on hemodialysis, should be closely monitored. If renal function decreases during treatment, Intron A Peg therapy should be discontinued.
Combination therapy
Patients with creatinine clearance < 50 ml/minute must not be treated with Intron A Peg in combination with ribavirin (see ribavirin SmPC). When administered in combination therapy, patients with impaired renal function should be more carefully monitored with respect to the development of anaemia.
Hepatic impairment
The safety and efficacy of Intron A Peg therapy has not been evaluated in patients with severe hepatic dysfunction, therefore Intron A Peg must not be used for these patients.
Elderly (> 65 years of age)
There are no apparent age-related effects on the pharmacokinetics of Intron A Peg. Data from elderly patients treated with a single dose of Intron A Peg suggest no alteration in Intron A Peg dose is necessary based on age.
Paediatric population
Intron A Peg can be used in combination with ribavirin in paediatric patients 3 years of age and older.
Method of administration
Intron A Peg should be administered as a subcutaneous injection. Patients may self-inject Intron A Peg if their physician determines that it is appropriate and with medical follow-up as necessary.
Intron A Peg pre-filled pen is to be removed from the refrigerator before administration to allow the solvent to reach room temperature (not more than 25°C).
Intron A Peg 50 micrograms powder and solvent for solution for injection in pre-filled pen
Each pre-filled pen (CLEARCLICK) is reconstituted with the solvent provided in the two-chamber cartridge (water for injections) for administration of up to 0.5 ml of solution. A small volume is lost during preparation of Intron A Peg for injection when the dose is measured and injected. Therefore, each pre-filled pen contains an excess amount of solvent and Intron A Peg powder to ensure delivery of the labelled dose in 0.5 ml of Intron A Peg, solution for injection. The reconstituted solution has a concentration of 50 micrograms in 0.5 ml.
Intron A Peg 80 micrograms powder and solvent for solution for injection in pre-filled pen
Each pre-filled pen (CLEARCLICK) is reconstituted with the solvent provided in the two-chamber cartridge (water for injections) for administration of up to 0.5 ml of solution. A small volume is lost during preparation of Intron A Peg for injection when the dose is measured and injected. Therefore, each pre-filled pen contains an excess amount of solvent and Intron A Peg powder to ensure delivery of the labelled dose in 0.5 ml of Intron A Peg, solution for injection. The reconstituted solution has a concentration of 80 micrograms in 0.5 ml.
Intron A Peg 100 micrograms powder and solvent for solution for injection in pre-filled pen
Each pre-filled pen (CLEARCLICK) is reconstituted with the solvent provided in the two-chamber cartridge (water for injections) for administration of up to 0.5 ml of solution. A small volume is lost during preparation of Intron A Peg for injection when the dose is measured and injected. Therefore, each pre-filled pen contains an excess amount of solvent and Intron A Peg powder to ensure delivery of the labelled dose in 0.5 ml of Intron A Peg, solution for injection. The reconstituted solution has a concentration of 100 micrograms in 0.5 ml.
Intron A Peg 120 micrograms powder and solvent for solution for injection in pre-filled pen
Each pre-filled pen (CLEARCLICK) is reconstituted with the solvent provided in the two-chamber cartridge (water for injections) for administration of up to 0.5 ml of solution. A small volume is lost during preparation of Intron A Peg for injection when the dose is measured and injected. Therefore, each pre-filled pen contains an excess amount of solvent and Intron A Peg powder to ensure delivery of the labelled dose in 0.5 ml of Intron A Peg, solution for injection. The reconstituted solution has a concentration of 120 micrograms in 0.5 ml.
Intron A Peg 150 micrograms powder and solvent for solution for injection in pre-filled pen
Each pre-filled pen (CLEARCLICK) is reconstituted with the solvent provided in the two-chamber cartridge (water for injections) for administration of up to 0.5 ml of solution. A small volume is lost during preparation of Intron A Peg for injection when the dose is measured and injected. Therefore, each pre-filled pen contains an excess amount of solvent and Intron A Peg powder to ensure delivery of the labelled dose in 0.5 ml of Intron A Peg, solution for injection. The reconstituted solution has a concentration of 150 micrograms in 0.5 ml.
Intron A Peg is injected subcutaneously after reconstituting the powder as instructed, attaching a needle and setting the prescribed dose. A complete and illustrated set of instructions is provided in the Annex to the Package Leaflet.
As for all parenteral medicinal products, the reconstituted solution is to be inspected visually prior to administration. The reconstituted solution should be clear and colourless. If discolouration or particulate matter is present, the reconstituted solution should not be used. After administering the dose, the Intron A Peg pre-filled pen and any unused solution contained in it is to be disposed of in accordance with local requirements.
