DOSAGE AND ADMINISTRATION
INTRON A Injection should be administered subcutaneously and REBETOL Capsules should be administered orally. REBETOL may be administered without regard to food, but should be administered in a consistent manner. (See CLINICAL PHARMACOLOGY.)
ADULTS
The recommended dose of REBETOL Capsules depends on the patient's body weight. The recommended doses of REBETOL and INTRON A are given in TABLE 7.
The recommended duration of treatment for patients previously untreated with interferon is 24 to 48 weeks. The duration of treatment should be individualized to the patient depending on baseline disease characteristics, response to therapy, and tolerability of the regimen (see Description of Clinical Studies and ADVERSE REACTIONS). After 24 weeks of treatment virologic response should be assessed. Treatment discontinuation should be considered in any patient who has not achieved an HCV RNA below the limit of detection of the assay by 24 weeks. There are no safety and efficacy data on treatment for longer than 48 weeks in the previously untreated patient population.
In patients who relapse following interferon therapy, the recommended duration of treatment is 24 weeks. There are no safety and efficacy data on treatment for longer than 24 weeks in the relapse patient population.
TABLE 7. Recommended Adult Dosing
|
Body weight
|
REBETOL Capsules
|
INTRON A Injection
|
|
</=75 kg
|
2 × 200-mg capsules AM,
3 × 200-mg capsules PM daily p.o.
|
3 million IU 3 times weekly s.c.
|
|
>75 kg
|
3 × 200-mg capsules AM,
3 × 200-mg capsules PM daily p.o.
|
3 million IU 3 times weekly s.c.
|
|
PEDIATRICS
Efficacy of REBETOL and INTRON A for pediatric patients has not been established. Based on pharmacokinetic data, the following doses of REBETOL and INTRON A provide similar exposures in pediatric patients as observed in adult patients treated with the approved doses of REBETOL and INTRON A (see TABLE 8).
Table 8. Pediatric Dosing
|
Body weight
|
REBETOL Capsules
|
INTRON A Injection
|
|
25-36 kg
|
1 × 200-mg capsule AM
1 × 200-mg capsule PM daily p.o.
|
3 million IU/m2 3 times weekly s.c.
|
|
37-49 kg
|
1 × 200-mg capsule AM
2 × 200-mg capsules PM daily p.o.
|
3 million IU/m2 3 times weekly s.c.
|
|
50-61 kg
|
2 × 200-mg capsules AM
2 × 200-mg capsules PM daily p.o.
|
3 million IU/m2 3 times weekly s.c.
|
|
>61 kg
|
Refer to adult dosing table
|
Refer to adult dosing table
|
|
Under no circumstances should REBETOL Capsules be opened, crushed, or broken (See CONTRAINDICATIONS and WARNINGS).
Dose Modifications (TABLE 9)
In clinical trials, approximately 26% of patients required modification of their dose of REBETOL Capsules, INTRON A Injection, or both agents. If severe adverse reactions or laboratory abnormalities develop during combination REBETOL/INTRON A therapy, the dose should be modified, or discontinued if appropriate, until the adverse reactions abate. If intolerance persists after dose adjustment, REBETOL/INTRON A therapy should be discontinued.
REBETOL/INTRON A therapy 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.)
For patients with a history of stable cardiovascular disease, a permanent dose reduction is required if the hemoglobin decreases by >/=2 g/dL during any 4-week period. In addition, for these cardiac history patients, if the hemoglobin remains <12 g/dL after 4 weeks on a reduced dose, the patient should discontinue combination REBETOL/INTRON A therapy.
It is recommended that a patient whose hemoglobin level falls below 10 g/dL have his/her REBETOL dose reduced to 600 mg daily (1 × 200-mg capsule AM, 2 × 200-mg capsules PM). A patient whose hemoglobin level falls below 8.5 g/dL should be permanently discontinued from REBETOL/INTRON A therapy. (See WARNINGS.)
It is recommended that a patient who experiences moderate depression (persistent low mood, loss of interest, poor self image, and/or hopelessness) have his/her INTRON A dose temporarily reduced and/or be considered for medical therapy. A patient experiencing severe depression or suicidal ideation/attempt should be discontinued from REBETOL/INTRON A therapy and followed closely with appropriate medical management. (See WARNINGS.)
TABLE 9. Guidelines for Dose Modifications
|
|
Dose Reduction *
REBETOL - Adults: 600 mg daily
Pediatrics: half the dose
INTRON A - Adults: 1.5 million IU TIW
Pediatrics: 1.5 million IU/m2 TIW
|
Permanent Discontinuation
of Treatment
REBETOL and INTRON A
|
|
Hemoglobin
|
<10 g/dL (REBETOL) Cardiac History Patients Only. >/=2 g/dL decrease during any 4-week period during treatment (REBETOL/INTRON A) |
<8.5 g/dL Cardiac History Patients Only.
<12 g/dL after 4 weeks of dose reduction |
|
White blood count
Neutrophil count
Platelet count
|
<1.5 × 109/L (INTRON A)
<0.75 × 109/L (INTRON A)
Adults: <50 × 109/L (INTRON A)
Pediatrics: <80 × 109/L
(INTRON A)
|
<1.0 × 109/L
<0.5 × 109/L
Adults: <25 × 109/L
Pediatrics: <50 × 109/L
|
|
*Study medication to be dose reduced is shown in parenthesis. |
|
Administration of INTRON A Injection
At the discretion of the physician, the patient may self-administer the INTRON A. (See illustrated MEDICATION GUIDE for instructions.)
The INTRON A Injection is supplied as a clear and colorless solution. The appropriate INTRON A dose should be withdrawn from the vial or set on the multidose pen and injected subcutaneously. The INTRON A Injection supplied with the B-D Safety Lok™ syringes contain a plastic sleeve to be pulled over the needle after use. The syringe locks with an audible click when the green stripe on the safety sleeve covers the red stripe on the needle. After administration of INTRON A Injection, it is essential to follow the procedure for proper disposal of syringes and needles. (See MEDICATION GUIDE for detailed instructions.)
| Vial/Pen Label Strength |
Fill Volume |
Concentration |
|
3 million IU vial
|
0.5 mL
|
3 million IU/0.5 mL
|
|
18 million IU multidose vial **/* |
3.8 mL
|
3 million IU/0.5 mL
|
|
18 million IU multidose pen # |
1.5 mL
|
3 million IU/0.2 mL
|
| **/* This is a multidose vial which contains a total of 22.8 million IU of interferon alfa-2b, recombinant per 3.8 mL in order to provide the delivery of six 0.5-mL doses, each containing 3 million IU of interferon alfa-2b, recombinant (for a label strength of 18 million IU). |
| #This is a multidose pen which contains a total of 22.5 million IU of interferon alfa-2b, recombinant per 1.5 mL in order to provide the delivery of six 0.2-mL doses, each containing 3 million IU of interferon alfa-2b, recombinant (for a label strength of 18 million IU). |
|
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. INTRON A Injection may be administered using either sterilized glass or plastic disposable syringes. Stability INTRON A Injection provided in vials is stable at 35°C (95°F) for up to 7 days and at 30°C (86°F) for up to 14 days. INTRON A Injection provided in a multidose pen is stable at 30°C (86°F) for up to 2 days. The solution is clear and colorless.
|
