DRUGS & SUPPLEMENTS
WARNING: RISK OF SERIOUS DISORDERS AND RIBAVIRIN-ASSOCIATED EFFECTSWARNING: RISK OF SERIOUS DISORDERS AND RIBAVIRINASSOCIATED EFFECTS
See full prescribing information for complete boxed warning.
The primary clinical toxicity of Ribavarin is hemolytic anemia. The anemia associated with Ribavarin therapy may result in worsening of cardiac disease and lead to fatal and nonfatal myocardial infarctions. Patients with a history of significant or unstable cardiac disease should not be treated with Ribavarin.
Significant teratogenic and/or embryocidal effects have been demonstrated in all animal species exposed to Ribavarin. In addition, Ribavarin has a multiple dose half-life of 12 days, and it may persist in non-plasma compartments for as long as 6 months. Therefore, Ribavarin, including Ribavarin, is contraindicated in women who are pregnant and in the male partners of women who are pregnant. Extreme care must be taken to avoid pregnancy during therapy and for 6 months after completion of therapy in both female patients and in female partners of male patients who are taking Ribavarin therapy. At least two reliable forms of effective contraception must be utilized during treatment and during the 6month post treatment follow-up period.
RECENT MAJOR CHANGESWarnings and Precautions (5.8) 08/2015
1 INDICATIONS AND USAGERibavarin is a nucleoside analogue indicated for the treatment of chronic hepatitis C (CHC) virus infection in combination with peginterferon alfa-2a in patients 5 years of age and older with compensated liver disease not previously treated with interferon alpha, and in adult CHC patients coinfected with HIV (1)
Ribavarin tablets in combination with peginterferon alfa-2a are indicated for the treatment of patients 5 years of age and older with chronic hepatitis C (CHC) virus infection who have compensated liver disease and have not been previously treated with interferon alpha.
The following points should be considered when initiating Ribavarin tablets combination therapy with peginterferon alfa-2a:
2 DOSAGE AND ADMINISTRATION
2.1 Chronic Hepatitis C MonoinfectionAdult Patients
The recommended dose of Ribavarin tablets is provided in Table 1. The recommended duration of treatment for patients previously untreated with Ribavarin and interferon is 24 to 48 weeks.
The daily dose of Ribavarin is 800 mg to 1200 mg administered orally in two divided doses. The dose should be individualized to the patient depending on baseline disease characteristics (e.g., genotype), response to therapy, and tolerability of the regimen (see Table 1).
Peginterferon alfa-2a is administered as 180 mcg/1.73m2 x BSA once weekly subcutaneously, to a maximum dose of 180 mcg, and should be given in combination with Ribavarin. The recommended treatment duration for patients with genotype 2 or 3 is 24 weeks and for other genotypes is 48 weeks.
Ribavarin should be given in combination with peginterferon alfa-2a. Ribavarin is available only as a 200 mg tablet and therefore the healthcare provider should determine if this sized tablet can be swallowed by the pediatric patient. The recommended doses for Ribavarin are provided in Table 2. Patients who initiate treatment prior to their 18th birthday should maintain pediatric dosing through the completion of therapy
2.2 Chronic Hepatitis C with HIV CoinfectionAdult Patients
The recommended dose for treatment of chronic hepatitis C in patients coinfected with HIV is peginterferon alfa-2a 180 mcg subcutaneous once weekly and Ribavarin 800 mg by mouth daily for a total duration of 48 weeks, regardless of HCV genotype.
2.3 Dose ModificationsAdult and Pediatric Patients
If severe adverse reactions or laboratory abnormalities develop during combination ribavirin/peginterferon alfa-2a therapy, the dose should be modified or discontinued, if appropriate, until the adverse reactions abate or decrease in severity. If intolerance persists after dose adjustment, ribavirin/peginterferon alfa-2a therapy should be discontinued. Table 3 provides guidelines for dose modifications and discontinuation based on the patient's hemoglobin concentration and cardiac status.
Ribavarin should be administered with caution to patients with pre-existing cardiac disease. Patients should be assessed before commencement of therapy and should be appropriately monitored during therapy. If there is any deterioration of cardiovascular status, therapy should be stopped [see WARNINGS AND PRECAUTIONS ].
Once Ribavarin has been withheld due to either a laboratory abnormality or clinical adverse reaction, an attempt may be made to restart Ribavarin at 600 mg daily and further increase the dose to 800 mg daily. However, it is not recommended that Ribavarin be increased to the original assigned dose (1000 mg to 1200 mg).
Upon resolution of a laboratory abnormality or clinical adverse reaction, an increase in Ribavarin dose to the original dose may be attempted depending upon the physician's judgment. If Ribavarin has been withheld due to a laboratory abnormality or clinical adverse reaction, an attempt may be made to restart Ribavarin at one-half the full dose.
2.4 Renal ImpairmentThe total daily dose of Ribavarin should be reduced for patients with creatinine clearance less than or equal to 50 mL/min; and the weekly dose of peginterferon alfa-2a should be reduced for creatinine clearance less than 30 mL/min as follows in Table 4 [see USE IN SPECIFIC POPULATIONS (8.7), PHARMACOKINETICS (12.3), and Peginterferon Alfa-2a PACKAGE INSERT].
No data are available for pediatric subjects with renal impairment.
2.5 Discontinuation of DosingDiscontinuation of peginterferon alfa-2a /ribavirin therapy should be considered if the patient has failed to demonstrate at least a 2 log10 reduction from baseline in HCV RNA by 12 weeks of therapy, or undetectable HCV RNA levels after 24 weeks of therapy.
Peginterferon alfa-2a/ribavirin therapy should be discontinued in patients who develop hepatic decompensation during treatment [see WARNINGS AND PRECAUTIONS (5.3)].
3 DOSAGE FORMS AND STRENGTHS
200 mg - light pink to pink, round, biconvex, beveled, film-coated tablets;
400 mg - light pink to pink, capsule shaped, biconvex, film-coated tablets;
500 mg - light pink to pink, modified capsule shaped, biconvex, film-coated tablets;
600 mg - light pink to pink, modified capsule shaped, biconvex, film-coated tablets
5 WARNINGS AND PRECAUTIONS
The Peginterferon alfa-2a Package Insert should be reviewed in its entirety for additional safety information prior to initiation of combination treatment.
5.1 PregnancyRibavarin may cause birth defects and/or death of the exposed fetus. Ribavarin has demonstrated significant teratogenic and/or embryocidal effects in all animal species in which adequate studies have been conducted. These effects occurred at doses as low as one twentieth of the recommended human dose of Ribavarin.
Ribavarin therapy should not be started unless a report of a negative pregnancy test has been obtained immediately prior to planned initiation of therapy. Extreme care must be taken to avoid pregnancy in female patients and in female partners of male patients. Patients should be instructed to use at least two forms of effective contraception during treatment and for 6 months after treatment has been stopped. Pregnancy testing should occur monthly during Ribavarin therapy and for 6 months after therapy has stopped [see BOXED WARNING, CONTRAINDICATIONS (4), USE IN SPECIFIC POPULATIONS (8.1), and PATIENT COUNSELING INFORMATION (17)].
5.2 AnemiaThe primary toxicity of Ribavarin is hemolytic anemia, which was observed in approximately 13% of all ribavirin/peginterferon alfa-2a- treated subjects in clinical trials. Anemia associated with Ribavarin occurs within 1 to 2 weeks of initiation of therapy. Because the initial drop in hemoglobin may be significant, it is advised that hemoglobin or hematocrit be obtained pretreatment and at week 2 and week 4 of therapy or more frequently if clinically indicated. Patients should then be followed as clinically appropriate. Caution should be exercised in initiating treatment in any patient with baseline risk of severe anemia [see DOSAGE AND ADMINISTRATION (2.3)].
Fatal and nonfatal myocardial infarctions have been reported in patients with anemia caused by Ribavarin. Patients should be assessed for underlying cardiac disease before initiation of Ribavarin therapy. Patients with pre-existing cardiac disease should have electrocardiograms administered before treatment, and should be appropriately monitored during therapy. If there is any deterioration of cardiovascular status, therapy should be suspended or discontinued [see DOSAGE AND ADMINISTRATION (2.3)]. Because cardiac disease may be worsened by drug-induced anemia, patients with a history of significant or unstable cardiac disease should not use Ribavarin [see BOXED WARNING, and DOSAGE AND ADMINISTRATION (2.3)].
5.3 Hepatic FailureChronic hepatitis C (CHC) patients with cirrhosis may be at risk of hepatic decompensation and death when treated with alpha interferons, including peginterferon alfa-2a. Cirrhotic CHC patients coinfected with HIV receiving highly active antiretroviral therapy (HAART) and interferon alfa-2a with or without Ribavarin appear to be at increased risk for the development of hepatic decompensation compared to patients not receiving HAART. In Study NR15961 [see CLINICAL STUDIES (14.3)], among 129 CHC/HIV cirrhotic patients receiving HAART, 14 (11%) of these patients across all treatment arms developed hepatic decompensation resulting in 6 deaths. All 14 patients were on NRTIs, including stavudine, didanosine, abacavir, zidovudine, and lamivudine. These small numbers of patients do not permit discrimination between specific NRTIs or the associated risk. During treatment, patients’ clinical status and hepatic function should be closely monitored for signs and symptoms of hepatic decompensation. Treatment with peginterferon alfa-2a/ Ribavarin should be discontinued immediately in patients with hepatic decompensation [see CONTRAINDICATIONS (4)]
5.4 HypersensitivitySevere acute hypersensitivity reactions have been observed during alpha interferon and Ribavarin therapy. If such a reaction occurs, therapy with peginterferon alfa-2a and Ribavarin should be discontinued immediately and appropriate medical therapy instituted. Serious skin reactions including vesiculobullous eruptions, reactions in the spectrum of Stevens-Johnson Syndrome (erythema multiforme major) with varying degrees of skin and mucosal involvement and exfoliative dermatitis (erythroderma) have been reported in patients receiving peginterferon alfa-2a with and without Ribavarin. Patients developing signs or symptoms of severe skin reactions must discontinue therapy [see ADVERSE REACTIONS (6.2)].
5.5 Pulmonary DisordersDyspnea, pulmonary infiltrates, pneumonitis, pulmonary hypertension, and pneumonia have been reported during therapy with Ribavarin and interferon. Occasional cases of fatal pneumonia have occurred. In addition, sarcoidosis or the exacerbation of sarcoidosis has been reported. If there is evidence of pulmonary infiltrates or pulmonary function impairment, patients should be closely monitored and, if appropriate, combination ribavirin/peginterferon alfa-2a treatment should be discontinued.
5.6 Bone Marrow SuppressionPancytopenia and bone marrow suppression have been reported in the literature to occur within 3 to 7 weeks after the concomitant administration of pegylated interferon/ribavirin and azathioprine. In this limited number of patients (n=8), myelotoxicity was reversible within 4 to 6 weeks upon withdrawal of both HCV antiviral therapy and concomitant azathioprine and did not recur upon reintroduction of either treatment alone. peginterferon alfa-2a, Ribavarin, and azathioprine should be discontinued for pancytopenia, and pegylated interferon/ribavirin should not be re-introduced with concomitant azathioprine [see Drug Interactions (7.3)].
5.7 PancreatitisRibavarin and peginterferon alfa-2a therapy should be suspended in patients with signs and symptoms of pancreatitis, and discontinued in patients with confirmed pancreatitis.
5.8 Impact on Growth in Pediatric PatientsDuring combination therapy for up to 48 weeks with peginterferon alfa-2a plus Ribavarin, growth inhibition was observed in pediatric subjects 5 to 17 years of age. Decreases in weight for age z-score and height for age z-score up to 48 weeks of therapy compared with baseline were observed. At 2 years post-treatment, 16% of pediatric subjects were more than 15 percentiles below their baseline weight curve and 11% were more than 15 percentiles below their baseline height curve.
The available longer term data on subjects who were followed up to 6 years post-treatment are too limited to determine the risk of reduced adult height in some patients .
5.9 Laboratory TestsBefore beginning ribavirin/peginterferon alfa-2a combination therapy, standard hematological and biochemical laboratory tests are recommended for all patients. Pregnancy screening for women of childbearing potential must be performed. Patients who have pre-existing cardiac abnormalities should have electrocardiograms administered before treatment with ribavirin/peginterferon alfa-2a.
After initiation of therapy, hematological tests should be performed at 2 weeks and 4 weeks and biochemical tests should be performed at 4 weeks. Additional testing should be performed periodically during therapy. In adult clinical studies, the CBC (including hemoglobin level and white blood cell and platelet counts) and chemistries (including liver function tests and uric acid) were measured at 1, 2, 4, 6, and 8 weeks, and then every 4 to 6 weeks or more frequently if abnormalities were found. In the pediatric clinical trial, hematological and chemistry assessments were at 1, 3, 5, and 8 weeks, then every 4 weeks. Thyroid stimulating hormone (TSH) was measured every 12 weeks. Monthly pregnancy testing should be performed during combination therapy and for 6 months after discontinuing therapy.
The entrance criteria used for the clinical studies of Ribavarin and peginterferon alfa-2a may be considered as a guideline to acceptable baseline values for initiation of treatment:
6 ADVERSE REACTIONSThe most common adverse reactions in adults receiving combination therapy are fatigue/asthenia, pyrexia, myalgia, and headache. (6.1)
The most common adverse reactions in pediatric subjects were similar to those seen in adults. (6.1)
To report SUSPECTED ADVERSE REACTIONS, contact Zydus Pharmaceuticals USA Inc. at 1-877-993-8779 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch
Peginterferon alfa-2a in combination with Ribavarin causes a broad variety of serious adverse reactions [see BOXED WARNING and WARNINGS AND PRECAUTIONS (5)]. The most common serious or life-threatening adverse reactions induced or aggravated by ribavirin/peginterferon alfa-2a include depression, suicide, relapse of drug abuse/overdose, and bacterial infections each occurring at a frequency of less than 1%. Hepatic decompensation occurred in 2% (10/574) CHC/HIV patients [see WARNINGS AND PRECAUTIONS (5.3)].
6.1 Clinical Studies ExperienceBecause clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.
In the pivotal registration trials NV15801 and NV15942, 886 patients received Ribavarin for 48 weeks at doses of 1000/1200 mg based on body weight. In these trials, one or more serious adverse reactions occurred in 10% of CHC monoinfected subjects and in 19% of CHC/HIV subjects receiving peginterferon alfa-2a alone or in combination with Ribavarin. The most common serious adverse event (3% in CHC and 5% in CHC/HIV) was bacterial infection (e.g., sepsis, osteomyelitis, endocarditis, pyelonephritis, pneumonia).
Other serious adverse reactions occurred at a frequency of less than 1% and included: suicide, suicidal ideation, psychosis, aggression, anxiety, drug abuse and drug overdose, angina, hepatic dysfunction, fatty liver, cholangitis, arrhythmia, diabetes mellitus, autoimmune phenomena (e.g., hyperthyroidism, hypothyroidism, sarcoidosis, systemic lupus erythematosus, rheumatoid arthritis), peripheral neuropathy, aplastic anemia, peptic ulcer, gastrointestinal bleeding, pancreatitis, colitis, corneal ulcer, pulmonary embolism, coma, myositis, cerebral hemorrhage, thrombotic thrombocytopenic purpura, psychotic disorder, and hallucination.
The percentage of patients in clinical trials who experienced one or more adverse events was 98%. The most commonly reported adverse reactions were psychiatric reactions, including depression, insomnia, irritability, anxiety, and flu-like symptoms such as fatigue, pyrexia, myalgia, headache and rigors. Other common reactions were anorexia, nausea and vomiting, diarrhea, arthralgias, injection site reactions, alopecia, and pruritus. Table 5 shows rates of adverse events occurring in greater than or equal to 5% of subjects receiving pegylated interferon and Ribavarin combination therapy in the CHC Clinical Trial, NV15801.
Ten percent of CHC monoinfected patients receiving 48 weeks of therapy with peginterferon alfa-2a in combination with Ribavarin discontinued therapy; 16% of CHC/HIV coinfected patients discontinued therapy. The most common reasons for discontinuation of therapy were psychiatric, flu-like syndrome (e.g., lethargy, fatigue, headache), dermatologic and gastrointestinal disorders, and laboratory abnormalities (thrombocytopenia, neutropenia, and anemia).
Overall 39% of patients with CHC or CHC/HIV required modification of peginterferon alfa-2a and/or Ribavarin therapy. The most common reason for dose modification of peginterferon alfa-2a in CHC and CHC/HIV patients was for laboratory abnormalities; neutropenia (20% and 27%, respectively) and thrombocytopenia (4% and 6%, respectively). The most common reason for dose modification of Ribavarin in CHC and CHC/HIV patients was anemia (22% and 16%, respectively).
Peginterferon alfa-2a dose was reduced in 12% of patients receiving 1000 mg to 1200 mg Ribavarin for 48 weeks and in 7% of patients receiving 800 mg Ribavarin for 24 weeks. Ribavarin dose was reduced in 21% of patients receiving 1000 mg to 1200 mg Ribavarin for 48 weeks and in 12% of patients receiving 800 mg Ribavarin for 24 weeks.
Chronic hepatitis C monoinfected patients treated for 24 weeks with peginterferon alfa-2a and 800 mg Ribavarin were observed to have lower incidence of serious adverse events (3% vs. 10%), hemoglobin less than 10g/dL (3% vs. 15%), dose modification of peginterferon alfa-2a (30% vs. 36%) and Ribavarin (19% vs. 38%), and of withdrawal from treatment (5% vs. 15%) compared to patients treated for 48 weeks with peginterferon alfa-2a and 1000 mg or 1200 mg Ribavarin. On the other hand, the overall incidence of adverse events appeared to be similar in the two treatment groups.
In a clinical trial with 114 pediatric subjects (5 to 17 years of age) treated with peginterferon alfa-2a alone or in combination with Ribavarin, dose modifications were required in approximately one-third of subjects, most commonly for neutropenia and anemia. In general, the safety profile observed in pediatric subjects was similar to that seen in adults. In the pediatric study, the most common adverse events in subjects treated with combination therapy peginterferon alfa-2a and Ribavarin for up to 48 weeks were influenza-like illness (91%), upper respiratory tract infection (60%), headache (64%), gastrointestinal disorder (56%), skin disorder (47%), and injection-site reaction (45%). Seven subjects receiving combination peginterferon alfa-2a and Ribavarin treatment for 48 weeks discontinued therapy for safety reasons (depression, psychiatric evaluation abnormal, transient blindness, retinal exudates, hyperglycemia, type 1 diabetes mellitus, and anemia). Severe adverse events were reported in 2 subjects in the peginterferon alfa-2a plus Ribavarin combination therapy group (hyperglycemia and cholecystectomy).
Growth Inhibition in Pediatric Subjects .
Pediatric subjects treated with PEGASYS plus Ribavarin combination therapy showed a delay in weight and height increases with up to 48 weeks of therapy compared with baseline. Both weight for age and height for age z-scores as well as the percentiles of the normative population for subject weight and height decreased during treatment. At the end of 2 years follow-up after treatment, most subjects had returned to baseline normative curve percentiles for weight (64th mean percentile at baseline, 60th mean percentile at 2 years post-treatment) and height (54th mean percentile at baseline, 56th mean percentile at 2 years post-treatment). At the end of treatment, 43% (23 of 53) of subjects experienced a weight percentile decrease of more than 15 percentiles, and 25% (13 of 53) experienced a height percentile decrease of more than 15 percentiles on the normative growth curves. At 2 years post-treatment, 16% (6 of 38) of subjects were more than 15 percentiles below their baseline weight curve and 11% (4 of 38) were more than 15 percentiles below their baseline height curve.
Thirty-eight of the 114 subjects enrolled in the long-term follow-up study, extending up to 6 years posttreatment. For most subjects, post-treatment recovery in growth at 2 years post-treatment was maintained to 6 years post-treatment.
Common Adverse Reactions in CHC with HIV Coinfection (Adults)
The adverse event profile of coinfected patients treated with peginterferon alfa-2a/ribavirin in Study NR15961 was generally similar to that shown for monoinfected patients in Study NV15801 (Table 5). Events occurring more frequently in coinfected patients were neutropenia (40%), anemia (14%), thrombocytopenia (8%), weight decrease (16%), and mood alteration (9%).
Laboratory Test Abnormalities
Anemia due to hemolysis is the most significant toxicity of Ribavarin therapy. Anemia (hemoglobin less than 10 g/dL) was observed in 13% of all Ribavarin and peginterferon alfa-2a combination-treated patients in clinical trials. The maximum drop in hemoglobin occurred during the first 8 weeks of initiation of Ribavarin therapy [see DOSAGE AND ADMINISTRATION (2.3)].
Decreases in hemoglobin, neutrophils and platelets may require dose reduction or permanent discontinuation from treatment [see DOSAGE AND ADMINISTRATION (2.4)]. Most laboratory abnormalities noted during the clinical trial returned to baseline levels shortly after discontinuation of treatment.
6.2 Postmarketing ExperienceThe following adverse reactions have been identified and reported during post-approval use of peginterferon alfa-2a/ribavirin combination therapy. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Blood and Lymphatic System disorders
Pure red cell aplasia
Ear and Labyrinth disorders
Hearing impairment, hearing loss
Serous retinal detachment
Liver and renal graft rejection
Metabolism and Nutrition disorders
Skin and Subcutaneous Tissue disorders
Stevens-Johnson Syndrome (SJS)
Toxic epidermal necrolysis (TEN)
7 DRUG INTERACTIONS
7.1 Nucleoside Reverse Transcriptase Inhibitors (NRTIs)In vitro data indicate Ribavarin reduces phosphorylation of lamivudine, stavudine, and zidovudine. However, no pharmacokinetic (e.g., plasma concentrations or intracellular triphosphorylated active metabolite concentrations) or pharmacodynamic (e.g., loss of HIV/HCV virologic suppression) interaction was observed when Ribavarin and lamivudine (n=18), stavudine (n=10), or zidovudine (n=6) were co-administered as part of a multi-drug regimen to HCV/HIV coinfected patients.
In Study NR15961 among the CHC/HIV coinfected cirrhotic patients receiving NRTIs, cases of hepatic decompensation (some fatal) were observed [see WARNINGS AND PRECAUTIONS (5.3)].
Patients receiving peginterferon alfa-2a/ribavirin and NRTIs should be closely monitored for treatment-associated toxicities. Physicians should refer to prescribing information for the respective NRTIs for guidance regarding toxicity management. In addition, dose reduction or discontinuation of peginterferon alfa-2a, Ribavarin or both should also be considered if worsening toxicities are observed, including hepatic decompensation (e.g., Child-Pugh greater than or equal to 6) [see WARNINGS AND PRECAUTIONS (5.3) and DOSAGE AND ADMINISTRATION (2.3)].
Co-administration of Ribavarin and didanosine is contraindicated. Didanosine or its active metabolite (dideoxyadenosine 5'-triphosphate) concentrations are increased when didanosine is co-administered with Ribavarin, which could cause or worsen clinical toxicities. Reports of fatal hepatic failure as well as peripheral neuropathy, pancreatitis, and symptomatic hyperlactatemia/lactic acidosis have been reported in clinical trials [see CONTRAINDICATIONS (4)].
In Study NR15961, patients who were administered zidovudine in combination with peginterferon alfa-2a/ribavirin developed severe neutropenia (ANC less than 500) and severe anemia (hemoglobin less than 8 g/dL) more frequently than similar patients not receiving zidovudine (neutropenia 15% vs. 9%) (anemia 5% vs. 1%). Discontinuation of zidovudine should be considered as medically appropriate.
7.2 Drugs Metabolized by Cytochrome P450In vitro studies indicate that Ribavarin does not inhibit CYP 2C9, CYP 2C19, CYP 2D6 or CYP 3A4.
7.3 AzathioprineThe use of Ribavarin to treat chronic hepatitis C in patients receiving azathioprine has been reported to induce severe pancytopenia and may increase the risk of azathioprine-related myelotoxicity. Inosine monophosphate dehydrogenase (IMDH) is required for one of the metabolic pathways of azathioprine. Ribavarin is known to inhibit IMDH, thereby leading to accumulation of an azathioprine metabolite, 6-methylthioinosine monophosphate (6-MTITP), which is associated with myelotoxicity (neutropenia, thrombocytopenia, and anemia). Patients receiving azathioprine with Ribavarin should have complete blood counts, including platelet counts, monitored weekly for the first month, twice monthly for the second and third months of treatment, then monthly or more frequently if dosage or other therapy changes are necessary [see WARNINGS AND PRECAUTIONS (5.6)].
8 USE IN SPECIFIC POPULATIONS
8.1 PregnancyTeratogenic Effects
Pregnancy: Category X.
Ribavarin produced significant embryocidal and/or teratogenic effects in all animal species in which adequate studies have been conducted. Malformations of the skull, palate, eye, jaw, limbs, skeleton, and gastrointestinal tract were noted. The incidence and severity of teratogenic effects increased with escalation of the drug dose. Survival of fetuses and offspring was reduced [see CONTRAINDICATIONS (4) and WARNINGS AND PRECAUTIONS (5.1)].
In conventional embryotoxicity/teratogenicity studies in rats and rabbits, observed no-effect dose levels were well below those for proposed clinical use (0.3 mg/kg/day for both the rat and rabbit; approximately 0.06 times the recommended daily human dose of Ribavarin). No maternal toxicity or effects on offspring were observed in a peri/postnatal toxicity study in rats dosed orally at up to 1 mg/kg/day (approximately 0.01 times the maximum recommended daily human dose of Ribavarin).
Treatment and Post-treatment: Potential Risk to the Fetus
Ribavarin is known to accumulate in intracellular components from where it is cleared very slowly. It is not known whether Ribavarin is contained in sperm, and if so, will exert a potential teratogenic effect upon fertilization of the ova. However, because of the potential human teratogenic effects of Ribavarin, male patients should be advised to take every precaution to avoid risk of pregnancy for their female partners.
Ribavarin should not be used by pregnant women or by men whose female partners are pregnant. Female patients of childbearing potential and male patients with female partners of childbearing potential should not receive Ribavarin unless the patient and his/her partner are using effective contraception (two reliable forms) during therapy and for 6 months post therapy [see CONTRAINDICATIONS (4)].
Ribavarin Pregnancy Registry
A Ribavarin Pregnancy Registry has been established to monitor maternal-fetal outcomes of pregnancies of female patients and female partners of male patients exposed to Ribavarin during treatment and for 6 months following cessation of treatment. Healthcare providers and patients are encouraged to report such cases by calling 1-800-593-2214.
8.3 Nursing MothersIt is not known whether Ribavarin is excreted in human milk. Because many drugs are excreted in human milk and to avoid any potential for serious adverse reactions in nursing infants from Ribavarin, a decision should be made either to discontinue nursing or therapy with Ribavarin, based on the importance of the therapy to the mother.
8.4 Pediatric UsePharmacokinetic evaluations in pediatric patients have not been performed.
Safety and effectiveness of Ribavarin have not been established in patients below the age of 5 years.
8.5 Geriatric UseClinical studies of Ribavarin and peginterferon alfa-2a did not include sufficient numbers of subjects aged 65 or over to determine whether they respond differently from younger subjects. Specific pharmacokinetic evaluations for Ribavarin in the elderly have not been performed. The risk of toxic reactions to this drug may be greater in patients with impaired renal function. The dose of Ribavarin should be reduced in patients with creatinine clearance less than or equal to 50 mL/min; and the dose of peginterferon alfa-2a should be reduced in patients with creatinine clearance less than 30 mL/min [see DOSAGE AND ADMINISTRATION ; USE IN SPECIFIC POPULATIONS (8.7)].
8.6 RaceA pharmacokinetic study in 42 subjects demonstrated there is no clinically significant difference in Ribavarin pharmacokinetics among Black (n=14), Hispanic (n=13) and Caucasian (n=15) subjects.
8.7 Renal ImpairmentRenal function should be evaluated in all patients prior to initiation of Ribavarin by estimating the patient's creatinine clearance.
A clinical trial evaluated treatment with Ribavarin and peginterferon alfa-2a in 50 CHC subjects with moderate or severe (creatinine clearance less than 30 mL/min) renal impairment or end stage renal disease (ESRD) requiring chronic hemodialysis (HD). In 18 subjects with ESRD receiving chronic HD, Ribavarin was administered at a dose of 200 mg daily with no apparent difference in the adverse event profile in comparison to subjects with normal renal function. Dose reductions and temporary interruptions of Ribavarin (due to ribavirin-related adverse reactions, mainly anemia) were observed in up to one-third ESRD/HD subjects during treatment; and only one-third of these subjects received Ribavarin for 48 weeks. Ribavarin plasma exposures were approximately 20% lower in subjects with ESRD on HD compared to subjects with normal renal function receiving the standard 1000/1200 mg Ribavarin daily dose.
Subjects with moderate (n=17) or severe (n=14) renal impairment did not tolerate 600 mg or 400 mg daily doses of Ribavarin, respectively, due to ribavirin-related adverse reactions, mainly anemia, and exhibited 20% to 30% higher Ribavarin plasma exposures (despite frequent dose modifications) compared to subjects with normal renal function (creatinine clearance greater than 80 mL/min) receiving the standard dose of Ribavarin. Discontinuation rates were higher in subjects with severe renal impairment compared to that observed in subjects with moderate renal impairment or normal renal function. Pharmacokinetic modeling and simulation indicate that a dose of 200 mg daily in patients with severe renal impairment and a dose of 200 mg daily alternating with 400 mg the following day in patients with moderate renal impairment will provide plasma Ribavarin exposure similar to patients with normal renal function receiving the approved regimen of Ribavarin. These doses have not been studied in patients [see DOSAGE AND ADMINISTRATION (2.4), and CLINICAL PHARMACOLOGY (12.3)].
Based on the pharmacokinetic and safety results from this trial, patients with creatinine clearance less than or equal to 50 mL/min should receive a reduced dose of Ribavarin; and patients with creatinine clearance less than 30 mL/min should receive a reduced dose of peginterferon alfa-2a. The clinical and hematologic status of patients with creatinine clearance less than or equal to 50 mL/min receiving Ribavarin should be carefully monitored. Patients with clinically significant laboratory abnormalities or adverse reactions which are persistently severe or worsening should have therapy withdrawn [see DOSAGE AND ADMINISTRATION (2.4), CLINICAL PHARMACOLOGY (12.3), and PEGINTERFERON ALFA-2A PACKAGE INSERT].
8.8 Hepatic ImpairmentThe effect of hepatic impairment on the pharmacokinetics of Ribavarin following administration of Ribavarin has not been evaluated. The clinical trials of Ribavarin were restricted to patients with Child-Pugh class A disease.
8.9 GenderNo clinically significant differences in the pharmacokinetics of Ribavarin were observed between male and female subjects.
Ribavarin pharmacokinetics, when corrected for weight, are similar in male and female patients.
8.10 Organ Transplant RecipientsThe safety and efficacy of peginterferon alfa-2a and Ribavarin treatment have not been established in patients with liver and other transplantations. As with other alpha interferons, liver and renal graft rejections have been reported on peginterferon alfa-2a, alone or in combination with Ribavarin [see ADVERSE REACTIONS (6.2)].
10 OVERDOSAGENo cases of overdose with Ribavarin have been reported in clinical trials. Hypocalcemia and hypomagnesemia have been observed in persons administered greater than the recommended dosage of Ribavarin. In most of these cases, Ribavarin was administered intravenously at dosages up to and in some cases exceeding four times the recommended maximum oral daily dose.
11 DESCRIPTIONRibavarin is a nucleoside analogue with antiviral activity. The chemical name of Ribavarin is 1-β-D-ribofuranosyl-1H-1,2,4-triazole-3-carboxamide and has the following structural formula:
The molecular formula of Ribavarin is C8H12N4O5 and the molecular weight is 244.2.
Ribavarin, USP is white, crystalline powder. It is freely soluble in water and slightly soluble in dehydrated alcohol.
Each film-coated Ribavarin tablet intended for oral administration contains 200 mg or 400 mg or 500 mg or 600 mg of Ribavarin. In addition, each tablet contains the following inactive ingredients: crospovidone, hypromellose, iron oxide red, iron oxide yellow, magnesium stearate, microcrystalline cellulose, polyethylene glycol, povidone, silicon dioxide, talc and titanium dioxide.
Organic test number pending in the USP.
12 CLINICAL PHARMACOLOGY
12.1 Mechanism of ActionRibavarin is an antiviral drug [see MICROBIOLOGY ].
12.3 PharmacokineticsMultiple dose Ribavarin pharmacokinetic data are available for HCV patients who received Ribavarin in combination with peginterferon alfa-2a. Following administration of 1200 mg/day with food for 12 weeks mean±SD (n=39; body weight greater than 75 kg) AUC0-12hr was 25,361±7110 ng·hr/mL and Cmax was 2748±818 ng/mL. The average time to reach Cmax was 2 hours. Trough Ribavarin plasma concentrations following 12 weeks of dosing with food were 1662±545 ng/mL in HCV infected patients who received 800 mg/day (n=89), and 2112±810 ng/mL in patients who received 1200 mg/day (n=75; body weight greater than 75 kg).
The terminal half-life of Ribavarin following administration of a single oral dose of Ribavarin is about 120 to 170 hours. The total apparent clearance following administration of a single oral dose of Ribavarin is about 26 L/h. There is extensive accumulation of Ribavarin after multiple dosing (twice daily) such that the Cmax at steady state was four-fold higher than that of a single dose.
Effect of Food on Absorption of Ribavarin
Bioavailability of a single oral dose of Ribavarin was increased by co-administration with a high-fat meal. The absorption was slowed (Tmax was doubled) and the AUC0-192h and Cmax increased by 42% and 66%, respectively, when Ribavarin was taken with a high-fat meal compared with fasting conditions [see DOSAGE AND ADMINISTRATION (2) and PATIENT COUNSELING INFORMATION (17)].
Elimination and Metabolism
The contribution of renal and hepatic pathways to Ribavarin elimination after administration of Ribavarin is not known. In vitro studies indicate that Ribavarin is not a substrate of CYP450 enzymes.
A clinical trial evaluated 50 CHC subjects with either moderate (creatinine clearance 30 to 50 mL/min) or severe (creatinine clearance less than 30 mL/min) renal impairment or end stage renal disease (ESRD) requiring chronic hemodialysis (HD). The apparent clearance of Ribavarin was reduced in subjects with creatinine clearance less than or equal to 50 mL/min, including subjects with ESRD on HD, exhibiting approximately 30% of the value found in subjects with normal renal function. Pharmacokinetic modeling and simulation indicates that a dose of 200 mg daily in patients with severe renal impairment and a dose of 200 mg daily alternating with 400 mg the following day in patients with moderate renal impairment will provide plasma Ribavarin exposures similar to that observed in patients with normal renal function receiving the standard 1000/1200 mg Ribavarin daily dose. These doses have not been studied in patients.
In 18 subjects with ESRD receiving chronic HD, Ribavarin was administered at a dose of 200 mg daily. Ribavarin plasma exposures in these subjects were approximately 20% lower compared to subjects with normal renal function receiving the standard 1000/1200 mg Ribavarin daily dose [see DOSAGE AND ADMINISTRATION (2.4), USE IN SPECIFIC POPULATIONS (8.7)].
Plasma Ribavarin is removed by hemodialysis with an extraction ratio of approximately 50%; however, due to the large volume of distribution of Ribavarin, plasma exposure is not expected to change with hemodialysis.
12.4 MicrobiologyMechanism of Action
The mechanism by which Ribavarin contributes to its antiviral efficacy in the clinic is not fully understood. Ribavarin has direct antiviral activity in tissue culture against many RNA viruses. Ribavarin increases the mutation frequency in the genomes of several RNA viruses and Ribavarin triphosphate inhibits HCV polymerase in a biochemical reaction.
Antiviral Activity in Cell Culture
In the stable HCV cell culture model system (HCV replicon), Ribavarin inhibited autonomous HCV RNA replication with a 50% effective concentration (EC50) value of 11 to 21 mcM. In the same model, PEG-IFN α-2a also inhibited HCV RNA replication, with an EC50 value of 0.1 to 3 ng/mL. The combination of PEG-IFN α-2a and Ribavarin was more effective at inhibiting HCV RNA replication than either agent alone.
Different HCV genotypes display considerable clinical variability in their response to PEG-IFN-α and Ribavarin therapy. Viral genetic determinants associated with the variable response have not been definitively identified.
Cross-resistance between IFN α and Ribavarin has not been observed.
13 NONCLINICAL TOXICOLOGY
13.1 Carcinogenesis, Mutagenesis, Impairment of FertilityCarcinogenesis
In a p53 mouse carcinogenicity study up to the maximum tolerated dose of 100 mg/kg/day, Ribavarin was not oncogenic. Ribavarin was also not oncogenic in a rat 2 year carcinogenicity study at doses up to the maximum tolerated dose of 60 mg/kg/day. On a body surface area basis, these doses are approximately 0.5 and 0.6 times the maximum recommended daily human dose of Ribavarin, respectively.
Ribavarin demonstrated mutagenic activity in the in vitro mouse lymphoma assay. No clastogenic activity was observed in an in vivo mouse micronucleus assay at doses up to 2000 mg/kg. However, results from studies published in the literature show clastogenic activity in the in vivo mouse micronucleus assay at oral doses up to 2000 mg/kg. A dominant lethal assay in rats was negative, indicating that if mutations occurred in rats they were not transmitted through male gametes.
Impairment of Fertility
In a fertility study in rats, Ribavarin showed a marginal reduction in sperm counts at the dose of 100 mg/kg/day with no effect on fertility. Upon cessation of treatment, total recovery occurred after 1 spermatogenesis cycle. Abnormalities in sperm were observed in studies in mice designed to evaluate the time course and reversibility of ribavirin-induced testicular degeneration at doses of 15 to 150 mg/kg/day (approximately 0.1 to 0.8 times the maximum recommended daily human dose of Ribavarin) administered for 3 to 6 months. Upon cessation of treatment, essentially total recovery from ribavirin-induced testicular toxicity was apparent within 1 or 2 spermatogenic cycles.
Female patients of childbearing potential and male patients with female partners of childbearing potential should not receive Ribavarin unless the patient and his/her partner are using effective contraception (two reliable forms). Based on a multiple dose half-life (t1/2) of Ribavarin of 12 days, effective contraception must be utilized for 6 months post therapy (i.e., 15 half-lives of clearance for Ribavarin).
No reproductive toxicology studies have been performed using peginterferon alfa-2a in combination with Ribavarin. However, peginterferon alfa-2a and Ribavarin when administered separately, each has adverse effects on reproduction. It should be assumed that the effects produced by either agent alone would also be caused by the combination of the two agents.
13.2 ANIMAL PHARMACOLOGY AND OR TOXICOLOGYIn a study in rats, it was concluded that dominant lethality was not induced by Ribavarin at doses up to 200 mg/kg for 5 days (up to 1.7 times the maximum recommended human dose of Ribavarin).
Long-term studies in the mouse and rat (18 to 24 months; dose 20 to 75, and 10 to 40 mg/kg/day, respectively, approximately 0.1 to 0.4 times the maximum daily human dose of Ribavarin) have demonstrated a relationship between chronic Ribavarin exposure and an increased incidence of vascular lesions (microscopic hemorrhages) in mice. In rats, retinal degeneration occurred in controls, but the incidence was increased in ribavirin-treated rats.
14 CLINICAL STUDIES
14.1 Chronic Hepatitis C PatientsAdult Patients
The safety and effectiveness of peginterferon alfa-2a in combination with Ribavarin for the treatment of hepatitis C virus infection were assessed in two randomized controlled clinical trials. All patients were adults, had compensated liver disease, detectable hepatitis C virus, liver biopsy diagnosis of chronic hepatitis, and were previously untreated with interferon. Approximately 20% of patients in both studies had compensated cirrhosis. Patients coinfected with HIV were excluded from these studies.
In Study NV15801, patients were randomized to receive either peginterferon alfa-2a 180 mcg subcutaneous once weekly with an oral placebo, peginterferon alfa-2a 180 mcg once weekly with Ribavarin 1000 mg by mouth (body weight less than 75 kg) or 1200 mg by mouth (body weight greater than or equal to 75 kg) or interferon alfa-2b 3 MIU subcutaneous three times a week plus Ribavarin 1000 mg or 1200 mg by mouth. All patients received 48 weeks of therapy followed by 24 weeks of treatment-free follow-up. Ribavarin or placebo treatment assignment was blinded. Sustained virological response was defined as undetectable (less than 50 IU/mL) HCV RNA on or after study week 68. Peginterferon alfa-2a in combination with Ribavarin resulted in a higher SVR compared to peginterferon alfa-2a alone or interferon alfa-2b and Ribavarin (Table 9). In all treatment arms, patients with viral genotype 1, regardless of viral load, had a lower response rate to peginterferon alfa-2a in combination with Ribavarin compared to patients with other viral genotypes.
In Study NV15942, all patients received peginterferon alfa-2a 180 mcg subcutaneous once weekly and were randomized to treatment for either 24 or 48 weeks and to a Ribavarin dose of either 800 mg or 1000 mg/1200 mg (for body weight less than 75 kg/ greater than or equal to 75 kg). Assignment to the four treatment arms was stratified by viral genotype and baseline HCV viral titer. Patients with genotype 1 and high viral titer (defined as greater than 2 x 106HCV RNA copies/mL serum) were preferentially assigned to treatment for 48 weeks.
Sustained Virologic Response (SVR) and HCV Genotype
HCV 1 and 4–Irrespective of baseline viral titer, treatment for 48 weeks with peginterferon alfa-2a and 1000 mg or 1200 mg of Ribavarin resulted in higher SVR (defined as undetectable HCV RNA at the end of the 24 week treatment-free follow-up period) compared to shorter treatment (24 weeks) and/or 800 mg Ribavarin.
HCV 2 and 3– Irrespective of baseline viral titer, treatment for 24 weeks with peginterferon alfa-2a and 800 mg of Ribavarin resulted in a similar SVR compared to longer treatment (48 weeks) and/or 1000 mg or 1200 mg of Ribavarin (see Table 10).
The numbers of patients with genotype 5 and 6 were too few to allow for meaningful assessment.
Previously untreated pediatric subjects 5 through 17 years of age (55% less than 12 years old) with chronic hepatitis C, compensated liver disease and detectable HCV RNA were treated with Ribavarin approximately 15 mg/kg/day plus peginterferon alfa-2a 180 mcg/1.73 m2 x body surface area once weekly for 48 weeks. All subjects were followed for 24 weeks post-treatment. Sustained virological response (SVR) was defined as undetectable (less than 50 IU/mL) HCV RNA on or after study week 68. A total of 114 subjects were randomized to receive either combination treatment of Ribavarin plus peginterferon alfa-2a or peginterferon alfa-2a monotherapy; subjects failing peginterferon alfa-2a monotherapy at 24 weeks or later could receive open-label Ribavarin plus peginterferon alfa-2a. The initial randomized arms were balanced for demographic factors; 55 subjects received initial combination treatment of Ribavarin plus peginterferon alfa-2a and 59 received peginterferon alfa-2a plus placebo; in the overall intent-to-treat population, 45% were female, 80% were Caucasian, and 81% were infected with HCV genotype 1. The SVR results are summarized in Table 11.
14.2 Other Treatment Response PredictorsTreatment response rates are lower in patients with poor prognostic factors receiving pegylated interferon alpha therapy. In studies NV15801 and NV15942, treatment response rates were lower in patients older than 40 years (50% vs. 66%), in patients with cirrhosis (47% vs. 59%), in patients weighing over 85 kg (49% vs. 60%), and in patients with genotype 1 with high vs. low viral load (43% vs. 56%). African-American patients had lower response rates compared to Caucasians.
In studies NV15801 and NV15942, lack of early virologic response by 12 weeks (defined as HCV RNA undetectable or greater than 2 log10 lower than baseline) was grounds for discontinuation of treatment. Of patients who lacked an early viral response by 12 weeks and completed a recommended course of therapy despite a protocol-defined option to discontinue therapy, 5/39 (13%) achieved an SVR. Of patients who lacked an early viral response by 24 weeks, 19 completed a full course of therapy and none achieved an SVR.
14.3 Chronic Hepatitis C/HIV Coinfected PatientsIn Study NR15961, patients with CHC/HIV were randomized to receive either peginterferon alfa-2a 180 mcg subcutaneous once weekly plus an oral placebo, peginterferon alfa-2a 180 mcg once weekly plus Ribavarin 800 mg by mouth daily or interferon alfa-2a, 3 MIU subcutaneous three times a week plus Ribavarin 800 mg by mouth daily. All patients received 48 weeks of therapy and sustained virologic response (SVR) was assessed at 24 weeks of treatment-free follow-up. Ribavarin or placebo treatment assignment was blinded in the peginterferon alfa-2a treatment arms. All patients were adults, had compensated liver disease, detectable hepatitis C virus, liver biopsy diagnosis of chronic hepatitis C, and were previously untreated with interferon. Patients also had CD4+ cell count greater than or equal to 200 cells/mm3 or CD4+ cell count greater than or equal to 100 cells/mm3 but less than 200 cells/mm3 and HIV-1 RNA less than 5000 copies/mL, and stable status of HIV. Approximately 15% of patients in the study had cirrhosis. Results are shown in Table 12.
Of the patients who did not demonstrate either undetectable HCV RNA or at least a 2 log10 reduction from baseline in HCV RNA titer by 12 weeks of peginterferon alfa-2a and Ribavarin combination therapy, 2% (2/85) achieved an SVR.
In CHC patients with HIV coinfection who received 48 weeks of peginterferon alfa-2a alone or in combination with Ribavarin treatment, mean and median HIV RNA titers did not increase above baseline during treatment or 24 weeks post-treatment.
16 HOW SUPPLIED/STORAGE AND HANDLINGRibavarin Tablets, 200 mg are light pink to pink, round, biconvex, beveled, film-coated tablets debossed with the logo of 'ZC19' on one side, other side plain and supplied as follows:
NDC 68382-046-03 in bottle of 168 tablets
NDC 68382-046-28 in bottle of 180 tablets
NDC 68382-046-10 in bottle of 1000 tablets
NDC 68382-046-77 in unit-dose blister cartons of 100 (10 x 10) unit-dose tablets
Ribavarin Tablets, 400 mg are light pink to pink, capsule shaped, biconvex, film-coated tablets debossed with 'ZD' and '07' on one side and plain on other side and supplied as follows:
NDC 68382-127-17 in bottle of 28 tablets
NDC 68382-127-07 in bottle of 56 tablets
NDC 68382-127-14 in bottle of 60 tablets
Ribavarin Tablets, 500 mg are light pink to pink, modified capsule shaped, biconvex, film-coated tablets debossed with 'ZC56' on one side and plain on the other side and supplied as follows:
NDC 68382-128-17 in bottle of 28 tablets
NDC 68382-128-07 in bottle of 56 tablets
NDC 68382-128-14 in bottle of 60 tablets
Ribavarin Tablets, 600 mg are light pink to pink, modified capsule shaped, biconvex, film-coated tablets debossed with 'ZD' and '08' on one side and plain on other side and supplied as follows:
NDC 68382-129-17 in bottle of 28 tablets
NDC 68382-129-07 in bottle of 56 tablets
NDC 68382-129-14 in bottle of 60 tablets
Storage and Handling
Store at 20° to 25°C (68° to 77°F).
Keep bottle tightly closed.
17 PATIENT COUNSELING INFORMATION
Patients must be informed that Ribavarin may cause birth defects and/or death of the exposed fetus. Ribavarin therapy must not be used by women who are pregnant or by men whose female partners are pregnant. Extreme care must be taken to avoid pregnancy in female patients and in female partners of male patients taking Ribavarin therapy and for 6 months post therapy. Patients should use two reliable methods of birth control while taking Ribavarin therapy and for 6 months post therapy. Ribavarin therapy should not be initiated until a report of a negative pregnancy test has been obtained immediately prior to initiation of therapy. Patients must perform a pregnancy test monthly during therapy and for 6 months post therapy.
Female patients of childbearing potential and male patients with female partners of childbearing potential must be advised of the teratogenic/embryocidal risks and must be instructed to practice effective contraception during Ribavarin therapy and for 6 months post therapy. Patients should be advised to notify the healthcare provider immediately in the event of a pregnancy [see CONTRAINDICATIONS (4) and WARNINGS AND PRECAUTIONS (5.1)].
The most common adverse event associated with Ribavarin is anemia, which may be severe [see BOXED WARNING, WARNINGS AND PRECAUTIONS (5.2) and ADVERSE REACTIONS (6.1)]. Patients should be advised that laboratory evaluations are required prior to starting Ribavarin therapy and periodically thereafter [see WARNINGS AND PRECAUTIONS (5.9)]. It is advised that patients be well hydrated, especially during the initial stages of treatment.
Patients who develop dizziness, confusion, somnolence, and fatigue should be cautioned to avoid driving or operating machinery.
Patients should be advised to take Ribavarin with food.
Patients should be questioned about prior history of drug abuse before initiating ribavirin/peginterferon alfa-2a, as relapse of drug addiction and drug overdoses have been reported in patients treated with interferons.
Patients should be advised not to drink alcohol, as alcohol may exacerbate chronic hepatitis C infection.
Patients should be informed about what to do in the event they miss a dose of Ribavarin. The missed doses should be taken as soon as possible during the same day. Patients should not double the next dose. Patients should be advised to call their healthcare provider if they have questions.
Patients should be informed that the effect of peginterferon alfa-2a/ribavirin treatment of hepatitis C infection on transmission is not known, and that appropriate precautions to prevent transmission of hepatitis C virus during treatment or in the event of treatment failure should be taken.
Patients should be informed regarding the potential benefits and risks attendant to the use of Ribavarin. Instructions on appropriate use should be given, including review of the contents of the enclosed MEDICATION GUIDE, which is not a disclosure of all or possible adverse effects.
Cadila Healthcare Ltd.
Zydus Pharmaceuticals USA Inc.
Pennington, NJ 08534
Read this Medication Guide carefully before you start taking Ribavarin and read the Medication Guide each time you get more Ribavarin. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or your treatment.
Also read the Medication Guide for peginterferon alfa-2a.
What is the most important information I should know about Ribavarin?
Ribavarin is a prescription medicine used with another medicine called peginterferon alfa-2a to treat chronic (lasting a long time) hepatitis C infection in people 5 years and older whose liver still works normally, and who have not been treated before with a medicine called an interferon alpha. It is not known if Ribavarin is safe and will work in children under 5 years of age.
Who should not take Ribavarin?
See "What is the most important information I should know about Ribavarin?"
Do not take Ribavarin if you:
What should I tell my healthcare provider before taking Ribavarin?
Before you take Ribavarin, tell your healthcare provider if you have or have had:
Especially tell your healthcare provider if you take any medicines to treat HIV, including didanosine (Videx or Videx EC), or if you take azathioprine (Imuran or Azasan).
Know the medicines you take. Keep a list of them to show your healthcare provider or pharmacist when you get a new medicine.
How should I take Ribavarin?
Ribavarin may cause serious side effects including:
See "What is the most important information I should know about Ribavarin?"
Common side effects of Ribavarin taken with peginterferon alfa-2a include:
These are not all the possible side effects of Ribavarin treatment. For more information, ask your healthcare provider or pharmacist.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Please address medical inquiries to, (MedicalAffairsRibavarinzydususa.com) Tel.: 1-877-993-8779.
How should I store Ribavarin?
General information about the safe and effective use of Ribavarin
It is not known if treatment with Ribavarin in combination with peginterferon alfa-2a will prevent an infected person from spreading the hepatitis C virus to another person while on treatment.
Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use Ribavarin for a condition for which it was not prescribed. Do not give Ribavarin to other people, even if they have the same symptoms that you have. It may harm them.
This Medication Guide summarizes the most important information about Ribavarin. If you would like more information, talk with your healthcare provider. You can ask your healthcare provider or pharmacist for information about Ribavarin that is written for healthcare professionals.
What are the ingredients in Ribavarin Tablets?
Active Ingredient: Ribavarin, USP
Inactive Ingredients: crospovidone, hypromellose, iron oxide red, iron oxide yellow, magnesium stearate, microcrystalline cellulose, polyethylene glycol, povidone, silicon dioxide, talc and titanium dioxide.
This Medication Guide has been approved by the U.S. Food and Drug Administration.
This product's label may have been updated. For current full prescribing information, please visit www.zydususa.com.
Cadila Healthcare Ltd.
Zydus Pharmaceuticals USA Inc.
Pennington, NJ 08534
NDC 68382-046-03 in bottle of 168 tablets
Ribavarin Tablets, 200 mg
NDC 68382-127-07 in bottle of 56 tablets
Ribavarin Tablets, 400 mg
NDC 68382-128-07 in bottle of 56 tablets
Ribavarin Tablets, 500 mg
NDC 68382-129-07 in bottle of 56 tablets
Ribavarin Tablets, 600 mg
Ribavarin tablets, 200 mg Ribavarin tablet,400 mg Ribavarin Tablet 500 mg Ribavarin tablet 600 mg
Ribavarin pharmaceutical active ingredients containing related brand and generic drugs:
Active ingredient is the part of the drug or medicine which is biologically active. This portion of the drug is responsible for the main action of the drug which is intended to cure or reduce the symptom or disease. The other portions of the drug which are inactive are called excipients; there role is to act as vehicle or binder. In contrast to active ingredient, the inactive ingredient's role is not significant in the cure or treatment of the disease. There can be one or more active ingredients in a drug.
Ribavarin available forms, composition, doses:
Form of the medicine is the form in which the medicine is marketed in the market, for example, a medicine X can be in the form of capsule or the form of chewable tablet or the form of tablet. Sometimes same medicine can be available as injection form. Each medicine cannot be in all forms but can be marketed in 1, 2, or 3 forms which the pharmaceutical company decided based on various background research results.
Composition is the list of ingredients which combinedly form a medicine. Both active ingredients and inactive ingredients form the composition. The active ingredient gives the desired therapeutic effect whereas the inactive ingredient helps in making the medicine stable.
Doses are various strengths of the medicine like 10mg, 20mg, 30mg and so on. Each medicine comes in various doses which is decided by the manufacturer, that is, pharmaceutical company. The dose is decided on the severity of the symptom or disease.
Ribavarin destination | category:
Destination is defined as the organism to which the drug or medicine is targeted. For most of the drugs what we discuss, human is the drug destination.
Drug category can be defined as major classification of the drug. For example, an antihistaminic or an antipyretic or anti anginal or pain killer, anti-inflammatory or so.
Ribavarin Anatomical Therapeutic Chemical codes:
A medicine is classified depending on the organ or system it acts [Anatomical], based on what result it gives on what disease, symptom [Therapeutical], based on chemical composition [Chemical]. It is called as ATC code. The code is based on Active ingredients of the medicine. A medicine can have different codes as sometimes it acts on different organs for different indications. Same way, different brands with same active ingredients and same indications can have same ATC code.
Ribavarin pharmaceutical companies:
Pharmaceutical companies are drug manufacturing companies that help in complete development of the drug from the background research to formation, clinical trials, release of the drug into the market and marketing of the drug.
Researchers are the persons who are responsible for the scientific research and is responsible for all the background clinical trials that resulted in the development of the drug.
Frequently asked QuestionsCan i drive or operate heavy machine after consuming Ribavarin?
Depending on the reaction of the Ribavarin after taken, if you are feeling dizziness, drowsiness or any weakness as a reaction on your body, Then consider Ribavarin not safe to drive or operate heavy machine after consumption. Meaning that, do not drive or operate heavy duty machines after taking the capsule if the capsule has a strange reaction on your body like dizziness, drowsiness. As prescribed by a pharmacist, it is dangerous to take alcohol while taking medicines as it exposed patients to drowsiness and health risk. Please take note of such effect most especially when taking Primosa capsule. It's advisable to consult your doctor on time for a proper recommendation and medical consultations.Is Ribavarin addictive or habit forming?
Medicines are not designed with the mind of creating an addiction or abuse on the health of the users. Addictive Medicine is categorically called Controlled substances by the government. For instance, Schedule H or X in India and schedule II-V in the US are controlled substances.
Please consult the medicine instruction manual on how to use and ensure it is not a controlled substance.In conclusion, self medication is a killer to your health. Consult your doctor for a proper prescription, recommendation, and guidiance.
ReviewsDrugs.com conducted a study on Ribavarin, and the result of the survey is set out below. It is noteworthy that the product of the survey is based on the perception and impressions of the visitors of the website as well as the views of Ribavarin consumers. We, as a result of this, advice that you do not base your therapeutic or medical decisions on this result, but rather consult your certified medical experts for their recommendations.
The information was verified by Dr. Arunabha Ray, MD Pharmacology