NEWS HIGHLIGHTS
Published Studies Related to Mycobutin (Rifabutin)
Efficacy of rifabutin-based triple therapy as second-line treatment to eradicate helicobacter pylori infection. [2007.07.25]
BACKGROUND: Rifabutin has been found to be effective in multi-resistant patients after various treatment cycles for Helicobacter pylori (HP) infection, but it has not been analysed as a second-line treatment. Therefore, we seek to compare the effectiveness of a treatment regimen including rifabutin versus conventional quadruple therapy (QT)... CONCLUSION: A 7-day rifabutin-based triple therapy associated to amoxicillin and omeprazole at standard dose was not found to be effective as a second-line rescue therapy. The problem with quadruple therapy lies in the adverse side effects it provokes. We believe the search should continue for alternatives that are more comfortably administered and that are at least as effective, but with fewer adverse side effects. TRIAL REGISTRATION: Current Controlled Trials ISRCTN81058036.
Two-year combination antibiotic therapy with clarithromycin, rifabutin, and clofazimine for Crohn's disease. [2007.06]
BACKGROUND & AIMS: Mycobacterium avium subspecies paratuberculosis has been proposed as a cause of Crohn's disease. We report a prospective, parallel, placebo-controlled, double-blind, randomized trial of 2 years of clarithromycin, rifabutin, and clofazimine in active Crohn's disease, with a further year of follow-up... CONCLUSIONS: Using combination antibiotic therapy with clarithromycin, rifabutin, and clofazimine for up to 2 years, we did not find evidence of a sustained benefit. This finding does not support a significant role for Mycobacterium avium subspecies paratuberculosis in the pathogenesis of Crohn's disease in the majority of patients. Short-term improvement was seen when this combination was added to corticosteroids, most likely because of nonspecific antibacterial effects.
Randomized trial of rifabutin-based triple therapy and high-dose dual therapy for rescue treatment of Helicobacter pylori resistant to both metronidazole and clarithromycin. [2006.07.15]
BACKGROUND: The clinical management of Helicobacter pylori infected patients who failed standard eradication therapies remains a challenge. AIM: To investigate the efficacy of rifabutin-based triple therapy and high-dose dual therapy for rescue treatment of H. pylori, and the correlation between cytochrome P450 2C19 (CYP2C19) polymorphisms and treatment outcome... CONCLUSIONS: Triple therapy with esomeprazole, rifabutin and amoxicillin and high-dose omeprazole/amoxicillin are comparable and effective and safe for rescue therapy of H. pylori regardless of the patient's CYP2C19 genotype.
Inhalable microparticles containing isoniazid and rifabutin target macrophages and 'stimulate the phagocyte' to achieve high efficacy. [2009.06]
Macrophage responses to infection with Mycobacterium tuberculosis (MTB) and treatment with soluble isoniazid (INH) plus rifabutin (RFB) versus microparticles containing equivalent amounts of drugs were compared. It was investigated whether macrophages driven to alternative activation upon infection with MTB could be rescued to display the classical activation phenotype...
Rifamycin-resistant Mycobacterium tuberculosis in the highly active antiretroviral therapy era: a report of 3 relapses with acquired rifampin resistance following alternate-day rifabutin and boosted protease inhibitor therapy. [2009.05.15]
Rifamycin-resistant Mycobacterium tuberculosis infection (i.e., by a strain of M. tuberculosis that is only resistant to rifamycins) occurs disproportionately among patients infected with the human immunodeficiency virus (HIV) who have a low CD4 cell count...
Clinical Trials Related to Mycobutin (Rifabutin)
TBTC Study 23B:Intensive PK of the Nelfinavir Rifabutin Interaction in Patients With HIV-TB [Completed]
Primary Objective:
To define the impact of nelfinavir (given at 1250mg bid as part of a combination
antiretroviral regimen) on peak levels and area under the curve for rifabutin and the
rifabutin metabolite, 25-O-desacetyl rifabutin when rifabutin is given at 300 mg bi-weekly as
part of tuberculosis chemotherapy.
Secondary Objectives:
To compare the pharmacokinetics of nelfinavir given twice daily at 1250 mg bid with
twice-weekly isoniazid and rifabutin to the pharmacokinetics of nelfinavir 1250 mg
twice-daily in historical HIV-infected patients not receiving isoniazid and rifabutin.
To evaluate the correlation between pharmacokinetic parameters of rifabutin and
25-O-desacetyl rifabutin and the occurrence of toxicity attributed to rifabutin in patients
with HIV-related tuberculosis.
To define detailed pharmacokinetics of isoniazid given at 15mg/kg or 900 mg in patients with
HIV-related tuberculosis.
To attempt to derive optimal sampling times for nelfinavir and rifabutin pharmacokinetic
studies.
TBTC Study 23A: Pharmacokinetics of Intermittent Isoniazid and Rifabutin in HIV-TB [Completed]
Primary Objectives:
1) To determine the proportion of patients with HIV-related tuberculosis who have abnormal
pharmacokinetic parameters for isoniazid and rifabutin.
Secondary Objectives:
1. To determine risk factors for abnormal pharmacokinetic parameters for isoniazid and
rifabutin.
2. To evaluate the correlation between pharmacokinetic parameters of isoniazid and
rifabutin and the occurrence of toxicity attributed to antituberculous therapy.
3. To evaluate the correlation between pharmacokinetic parameters of isoniazid and
rifabutin and the efficacy of TB therapy.
4. To define and correlate phenotypic INH acetylator status with the results of genotypic
acetylator data obtained in the parent trial.
TBTC Study 23C: Pharmacokinetics of Intermittent Rifabutin and Isoniazid With Daily Efavirenz [Completed]
The aim of this trial is to study the efavirenz-rifabutin interaction. Thus, this trial will
enroll patients with HIV and tuberculosis co-infections who are receiving a rifabutin-based
regimen and who plan to begin an antiretroviral regimen containing efavirenz dosed at 600 mg
daily. Enrollment in TB Trials Consortium Study 23 is not a requirement for participation in
this study.
Primary Objective:
To compare the pharmacokinetics of rifabutin at 600 mg twice a week in combination with
efavirenz 600 mg daily to the pharmacokinetics of rifabutin 300 mg twice a week without
efavirenz.
A Study of Rifabutin, Used Alone or With Ethambutol in the Prevention of Mycobacterium Avium Complex (MAC) Bacteremia in Patients With AIDS [Completed]
To optimize Mycobacterium avium Complex (MAC) prophylaxis in AIDS patients by measuring serum
rifabutin levels and adjusting the dose accordingly. To combine rifabutin with ethambutol to
examine the effect of combination therapy in preventing or delaying the incidence of MAC
bacteremia in this patient population.
The Safety and Effectiveness of Rifabutin, Combined With Clarithromycin or Azithromycin, in HIV-Infected Patients [Completed]
PER 03/10/94 AMENDMENT: PART B. To determine whether there is an effect on plasma drug levels
of azithromycin and rifabutin as measured by changes in the plasma concentration-time curve
(AUC) when these drugs are taken concomitantly.
ORIGINAL PRIMARY: To gain preliminary information about the safety and tolerance of
clarithromycin and azithromycin in combination with rifabutin (three potential agents against
Mycobacterium avium-intracellulare) in HIV-infected patients with CD4 counts < 200
cells/mm3.
ORIGINAL SECONDARY: To determine whether there is an effect on the pharmacokinetics of the
macrolide antibiotics or rifabutin when these drugs are taken concomitantly. To monitor the
effect of rifabutin therapy on dapsone serum levels in patients taking dapsone for PCP
prophylaxis. To monitor the effect of macrolide/rifabutin combination therapies on AZT or ddI
serum levels.
Two new macrolide antibiotics, clarithromycin and azithromycin, and rifabutin (a rifamycin
derivative) have all demonstrated in vitro and in vivo activity against Mycobacterium
avium-intracellulare, a common systemic bacterial infection complicating AIDS. Further
information is needed, however, regarding the clinical and pharmacokinetic interaction of
these drugs used in combination.
|
