Rifabutin

Rifampicin, the only commercially available ansamacroHde, is manufactured by MerreU Dow under the tradename Rifadin, and by CIBA under the trade name Rimactane. Rifampicin is also suppHed in combination with isoniazid or pyrazinamide [98-96-4]. The rifampicin—isoniazid combination is known as Rifamate (MerreU Dow), Rifinah (MerreU Dow), and Rimactazid (CIBA) the rifampicin—pyrazinamide as Rifater (MerreU Dow). Several other rifamycin derivatives including rifabutin and rifapentine are undergoing clinical studies. 

Antimicrobial spectrum, pharmacodynamic and phamacokinetic characteristics of rifabutin, a long-acting antituberculosis semisynthetic antibiotic of rifam-icin group 99MI13. 

A newly introduced rifamyein is rifabutin. This may be used in the prophylaxis of M. avium complex infeetions in immunoeompromised patients and in the treatment, with other drugs, of non-tubereulous myeobacterial infeetions. 

P-lactam antimicrobials, gatifloxacin, indinavir, isoniazid, levofloxacin, nitrofurantoin, ribavirin, rifabutin, rifampin, silver sulfadiazine, streptomycin, sulfonamide antimicrobials, and tetracyclines... 

Rifampin, rifabutin Increase metabolism of COCs Decrease efficacy of COCs backup method of contraception is recommended... 

Rifampin Daily for 4 months For persons who are contacts of patients with isoniazid-resistant rifampin susceptible TB. In HIV-infected patients, protease inhibitors or NNRTIs generally should not be administered concurrently with rifampin rifabutin can be used as an alternative for patients treated with indinavir, nelfinavir, amprenivir, ritonavir, orefavirenz, and possibly with nevirapine or soft-gel saquinavir5 B (II) B (III)... 

Rifabutin Adults0 5 mg/kg (300 mg) Children Appropriate dosing unknown Hematologic toxicity, uveitis, gastrointestinal symptoms, polyarthralgias, hepatotoxicity, pseudojaundice (skin discoloration with normal bilirubin), rash, flulike syndrome, orange discoloration of bodily fluids (sputum, urine, sweat, tears) Drug interactions are less problematic than rifampin... 

Antimicrobial resistance to rifamycins develops rapidly both in vitro and in vivo [65,85,86], As a consequence, all the three members of the family (i.e. rifampicin, rifabutin and rifapentine) are used clinically as components of combination therapies [65,87], Being structurally related, rifaximin could share this potential. And indeed resistance rates, recorded in fecal strains of Enterobacteriaceae, Enterococcus, Bacteroides, Clostridium and anaerobic cocci, ranged between 30 and 90% after short-term (5 days) antibiotic (800 mg daily) treatment [82], A similar pattern was observed in 10 patients with hepatic encephalopathy after treatment with rifaximin 1,200 mg/day for 5 days [80]. 

Pilotto A, Franceschi M, Rassu M, Furlan F, Scagnelli M In vitro activity of rifabutin against strains of Helicobacter pylori resistant to metronidazole and clarithromycin. Am J Gastroenterol 2000 95 833-834. 

Heep M, Beck D, Bayerdorlfer E, Lehn N Rifampin and rifabutin resistance mechanism in Helicobacter pylori. Antimicrob Agents Chemother 1999 43 1497-1499. 

Gisbert JP, Calvet X, Bujanda L, Marcos S, Gisbert JL, Pajares JM Rescue therapy with rifabutin after multiple Helicobacter pylori treatment failures. Helicobacter 2003 8 90-94. 

Wong WM, Gu Q, Lam SK, Fung FM, Lai KC, Hu WH, Yee YK, Chan CK, Xia HH, Yuen MF, Wong BC Randomized controlled study of rabeprazole, levofloxacin and rifabutin triple therapy vs. quadruple therapy as second-line treatment for Helicobacter pylori infection. Aliment Pharmacol Ther 2003 17 553-560. 

Perri F, Festa V, Clemente R, Quitadamo M, Andriulli A Rifabutin-based rescue therapy for Helicobacter pylori infected patients after failure of standard regimens. Aliment Pharmacol Ther 2000 14 311—316. 

Clarilhromycin 500 mg orally twice daily, plus ethambutol 15 mg/kg/day orally (Al), and For advanced disease, rifabutin 300 rng/day (dose may need adjustment with ART) (Al) ... 

Rifampin 600 mg orally once daily (AIN) or rifabutin 300 mg orally once daily (Bill) for 4 months... 

Rifampin (RIF) 600 mg daily for 4 months can be used when INH resistance is suspected or when the patient cannot tolerate INH. Rifabutin 300 mg daily may be substituted for RIF for patients at high risk of drug interactions. 

Already, the virion-associated reverse transcriptase has been highlighted as a target. The RT gene has been cloned, and the gene product can be produced in large quantities. Several molecules of very diverse molecular structure, such as zidovudine, suramin, and rifabutin, have been shown to cause inhibition of the... 

The rifamycins are a group of antibiotics of large size (Mr close to 1,000), which, among other chemical similarities, have an acetyl group at position 25. Deacetylation by carboxylesterases is a major metabolic pathway in animals and humans, as seen for example with rifampin, rifabutin, and rifalazil [97] [98],... 

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