Class: Antituberculosis agent
- Tablets 150 mg
Inhibits DNA-dependent RNA polymerase in susceptible strains of Mycobacterium tuberculosis . Bactericidal for intracellular and extracellular M. tuberculosis organisms.
Rapid and well absorbed. Absolute bioavailability is not determined. Relative bioavailability is 70% (oral solution). T max is 5 to 6 h (rifapentine); 11.25 h (metabolite). C max is 15.05 mcg/mL (rifapentine); 6.26 mcg/mL (25-desacetyl rifapentine metabolite). Food increased AUC and C max . Steady state is 10 days.
Vd is 70 L. Protein binding is 97.7% (rifapentine) and 93.2% (25-desacetyl rifapentine metabolite). Both bound mainly to albumin.
Hepatic; rifapentine undergoes enzymatic transformation to active 25-desacetyl rifapentine.
Eliminated in urine (17%) and feces (70%).
Indications and Usage
Treatment of pulmonary tuberculosis in conjunction with 1 or more other antituberculosis drugs to which the isolate is susceptible.
Hypersensitivity to any of the rifamycins (rifabutin, rifampin).
Dosage and AdministrationAdults and children (12 yr of age or older)
PO Intensive phase: 600 mg twice weekly (with an interval of 3 days or more) for 2 mo. Continuation phase: 600 mg once weekly for 4 mo.
Store tablets at controlled room temperature (59° to 86°F). Protect from excessive heat and humidity.
Drug InteractionsAmitriptyline, amprenavir, azole antifungal agents, barbiturates, buspirone, chloramphenicol, clarithromycin, clofibrate, clozapine, corticosteroids, cyclosporine, dapsone, delavirdine, diazepam, diltiazem, digitalis glycosides, disopyramide, doxycycline, erythromycin, fluconazole, fluoroquinolones, haloperidol, indinavir, itraconazole, ketoconazole, levothyroxine, losartan, methadone, mexiletine, morphine, nelfinavir, nifedipine, nortriptyline, ondansetron, oral contraceptives, phenytoin, progestins, quinidine, quinine, ritonavir, saquinavir, sildenafil, sulfonylureas, tacrolimus, tamoxifen, theophylline, tocainide, toremifene, tricyclic antidepressants, troleandomycin, verapamil, warfarin, zidovudine, zolpidem
Has same interaction potential as rifampin. Potent inducer of hepatic drug metabolizing enzymes. Reduced levels and efficacy of target drugs may occur.Ketoconazole
May reduce rifapentine plasma levels, decreasing the therapeutic effects.
Laboratory Test Interactions
May alter microbiological assays for folate and vitamin B 12 .
The following adverse reactions were reported in patients receiving rifapentine combination therapy and occurred in at least 1% of the patients.
Rash; acne; pruritus; maculopapular rash.
Anorexia; nausea; vomiting; dyspepsia; diarrhea; hemoptysis.
Pyuria; proteinuria; hematuria; urinary casts.
Neutropenia; lymphopenia; anemia; leukopenia; thrombocytosis.
Increased AST and ALT; hepatitis.
Arthralgia; pain; hyperuricemia.
Conduct baseline measurements of hepatic enzymes, bilirubin, CBC, and platelet counts. Question patients monthly concerning symptoms of adverse reactions. Follow up on abnormalities, including laboratory tests.
Category C .
Safety and efficacy not established in children younger than 12 yr of age.
Use with caution because of the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant diseases or other drug therapy.
Use with caution under strict medical supervision.
May produce a reddish-orange discoloration of the feces, urine, saliva, sweat, sputum, tears, and other body fluids. Contact lenses or dentures may become permanently discolored.
May occur from competition for excretory pathways between rifapentine and bilirubin.
Do not use in patients with porphyria.
Should be considered in patients in whom diarrhea develops.
Headache, urinary frequency, heartburn, transient elevations of hepatic enzymes.
- Review dosing schedule and prescribed length of therapy with patient.
- Ensure patient understands treatment will be lengthy and the entire course of treatment, including companion drugs, must be completed to avoid relapse or development of resistance. Emphasize the importance of not missing any doses of any tuberculosis medications.
- Advise patient to take each dose without regard to meals but to take with food if stomach upset occurs.
- Advise patient that rifapentine may produce a red/orange discoloration of body tissues and fluids (eg, skin, teeth, tongue, urine, feces, saliva, sputum, tears, sweat, breast milk). Caution patient that contact lenses or dentures may be permanently stained.
- Advise patient to contact health care provider immediately of any of the following: fever; general body discomfort; persistent nausea or vomiting; dark urine; yellowing of skin or eyes; pain or swelling of the joints.
- Warn patient that diarrhea containing blood or pus may be a sign of a serious disorder and to seek medical care if noted and not treat at home.
- Caution women using oral or parenteral hormonal contraception that rifapentine will reduce the effectiveness of contraceptive and to change to nonhormonal methods of contraception (eg, condoms, diaphragm) to prevent pregnancy.
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