ANTIRETROVIRALS |
Amprenavir | 1200 mg twice a day for 10 days | 300 mg once a day for 10 days | Healthy male subjects (6) | ↑ AUC by 193%, ↑ Cmax by 119% | ↔ | Reduce rifabutin dose by at least 50%. Monitor closely for adverse reactions. |
Bictegravir | 75 mg once a day | 300 mg once a day (fasted) | Healthy subjects | ND | ↓ AUC 38% ↓ Cmin 56% ↓ Cmax 20% | Co-administration of rifabutin with Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide) is not recommended due to an expected decrease in tenofovir alafenamide in addition to the reported reduction in bictegravir. Refer to Biktarvy prescribing information for additional information |
Delavirdine | 400 mg three times a day | 300 mg once a day | HIV-infected patients (7) | ↑ AUC by 230%, ↑ Cmax by 128% | ↓ AUC by 80%, ↓ Cmax by 75%, ↓ Cmin by 17% | CONTRAINDICATED |
Didanosine | 167 or 250 mg twice a day for 12 days | 300 or 600 mg once a day for 12 days | HIV-infected patients (11) | ↔ | ↔ | |
Doravirine | 100 mg single dose | 300 mg once a day for 16 days | Healthy subjects (12) | ND | ↓ 50% in AUC, ↓ 68% in C24 ↔ in Cmax | If concomitant use is necessary, increase the doravirine dosage as instructed in doravirine-containing product prescribing information. |
Fosamprenavir/ ritonavir | 700 mg twice a day plus ritonavir 100 mg twice a day for 2 weeks | 150 mg every other day for 2 weeks | Healthy subjects (15) | ↔ AUC* ↓ Cmax by 15% | ↑ AUC by 35%†, ↑ Cmax by 36%, ↑ Cmin by 36% | Reduce rifabutin dose by at least 75% (to a maximum 150 mg every other day or three times per week) when given with fosamprenavir/ritonavir combination. |
Indinavir | 800 mg three times a day for 10 days | 300 mg once a day for 10 days | Healthy subjects (10) | ↑ AUC by 173%, ↑ Cmax by 134% | ↓ AUC by 34%, ↓ Cmax by 25%, ↓ Cmin by 39% | Reduce rifabutin dose by 50%, and increase indinavir dose from 800 mg to 1000 mg three times a day. |
Lopinavir/ ritonavir | 400/100 mg twice a day for 20 days | 150 mg once a day for 10 days | Healthy subjects (14) | ↑ AUC by 203% ‡ ↓ Cmax by 112% | ↔ | Reduce rifabutin dose by at least 75% (to a maximum 150 mg every other day or three times per week) when given with lopinavir/ritonavir combination. Monitor closely for adverse reactions. Reduce rifabutin dosage further, as needed. |
Saquinavir/ ritonavir | 1000/100 mg twice a day for 14 or 22 days | 150 mg every 3 days for 21–22 days | Healthy subjects | ↑ AUC by 53% § ↑ Cmax by 88% (n=11) | ↓ AUC by 13%, ↓ Cmax by 15%, (n=19) | Reduce rifabutin dose by at least 75% (to a maximum 150 mg every other day or three times per week) when given with saquinavir/ritonavir combination. Monitor closely for adverse reactions. |
Rilpivirine | 25 mg once a day | 300 mg once a day | Healthy subjects (18) | ND | ↓ AUC by 42% ↓ Cmin by 48% ↓ Cmax by 31% | Co-administration of rifabutin with Odefsey (rilpivirine/tenofovir alafenamide/emtricitabine) is not recommended, due to an expected decrease in tenofovir alafenamide in addition to the reported reduction in rilpivirine. Refer to Odefsey prescribing information for additional information. |
Ritonavir | 500 mg twice a day for 10 days | 150 mg once a day for 16 days | Healthy subjects (5) | ↑ AUC by 300%, ↑ Cmax by 150% | ND | Reduce rifabutin dose by at least 75% (to a maximum 150 mg every other day or three times per week) when given with lopinavir/ritonavir combination. Monitor closely for adverse reactions. Reduce rifabutin dosage further, as needed. |
Tipranavir/ ritonavir | 500/200 twice a day for 15 doses | 150 mg single dose | Healthy subjects (20) | ↑ AUC by 190%, ↑ Cmax by 70% | ↔ | Reduce rifabutin dose by at least 75% (to a maximum 150 mg every other day or three times per week) when given with tipranavir/ritonavir combination. Monitor closely for adverse reactions. Reduce rifabutin dosage further, as needed. |
Nelfinavir | 1250 mg twice a day for 7–8 days | 150 mg once a day for 8 days | HIV-infected patients (11) | ↑ AUC by 83%, ¶ ↑ Cmax by 19% | ↔ | Reduce rifabutin dose by 50% (to 150 mg once a day) and increase the nelfinavir dose to 1250 mg twice a day. |
Zidovudine | 100 or 200 mg every four hours | 300 or 450 mg once a day | HIV-infected patients (16) | ↔ | ↓ AUC by 32%, ↓ Cmax by 48%, | Because zidovudine levels remained within the therapeutic range during co-administration of rifabutin, dosage adjustments are not necessary. |
ANTIFUNGALS |
Fluconazole | 200 mg once a day for 2 weeks | 300 mg once a day for 2 weeks | HIV-infected patients (12) | ↑ AUC by 82%, ↑ Cmax by 88% | ↔ | Monitor for rifabutin associated adverse events. Reduce rifabutin dose or suspend MYCOBUTIN use if toxicity is suspected. |
Posaconazole | 200 mg once a day for 10 days | 300 mg once a day for 17 days | Healthy subjects (8) | ↑ AUC by 72%, ↑ Cmax by 31% | ↓ AUC by 49%, ↓ Cmax by 43% | If co-administration of these two drugs cannot be avoided, patients should be monitored for adverse events associated with rifabutin administration, and lack of posaconazole efficacy. |
Itraconazole | 200 mg once a day | 300 mg once a day | HIV-Infected patients (6) | ↑# | ↓ AUC by 70%, ↓ Cmax by 75%, | If co-administration of these two drugs cannot be avoided, patients should be monitored for adverse events associated with rifabutin administration, and lack of itraconazole efficacy. In a separate study, one case of uveitis was associated with increased serum rifabutin levels following co-administration of rifabutin (300 mg once a day) with itraconazole (600–900 mg once a day). |
Voriconazole | 400 mg twice a day for 7 days (maintenance dose) | 300 mg once a day for 7 days | Healthy male subjects (12) | ↑ AUC by 331%, ↑ Cmax by 195% | ↑ AUC by ~100%, ↑ Cmax by ~100%Þ | CONTRAINDICATED |
ANTI-PCP (Pneumocystis carinii pneumonia) |
Dapsone | 50 mg once a day | 300 mg once a day | HIV-infected patients (16) | ND | ↓ AUC by 27 –40% | |
Sulfamethoxazole- Trimethoprim | 800/160 mg | 300 mg once a day | HIV-infected patients (12) | ↔ | ↓ AUC by 15–20% | |
ANTI-MAC (Mycobacterium avium intracellulare complex) |
Azithromycin | 500 mg once a day for 1 day, then 250 mg once a day for 9 days | 300 mg once a day | Healthy subjects (6) | ↔ | ↔ | |
Clarithromycin | 500 mg twice a day | 300 mg once a day | HIV-infected patients (12) | ↑ AUC by 75% | ↓ AUC by 50% | Monitor for rifabutin associated adverse events. Reduce dose or suspend use of MYCOBUTIN if toxicity is suspected. Alternative treatment for clarithromycin should be considered when treating patients receiving rifabutin |
ANTI-TB (Tuberculosis) |
Ethambutol | 1200 mg | 300 mg once a day for 7 days | Healthy subjects (10) | ND | ↔ | |
Isoniazid | 300 mg | 300 mg once a day for 7 days | Healthy subjects (6) | ND | ↔ | |
OTHER |
Methadone | 20 – 100 mg once a day | 300 mg once a day for 13 days | HIV-infected patients (24) | ND | ↔ | |
Ethinylestradiol (EE)/Norethindrone (NE) | 35 mg EE / 1 mg NE for 21 days | 300 mg once a day for 10 days | Healthy female subjects (22) | ND | EE: ↓ AUC by 35%, ↓ Cmax by 20% NE: ↓ AUC by 46% | Patients should be advised to use additional or alternative methods of contraception. |
Theophylline | 5 mg/kg | 300 mg for 14 days | Healthy subjects (11) | ND | ↔ | |