Tybost

TYBOST is a CYP3A inhibitor indicated to increase systemic exposure of atazanavir or darunavir (once daily dosing regimen) in combination with other antiretroviral agents in the treatment of HIV-1 infection in adults and in pediatric patients weighing at least 14 kg. ( 1.1 ) Limitations of Use : TYBOST is not interchangeable with ritonavir to increase systemic exposure of darunavir 600 mg twice daily, fosamprenavir, saquinavir, or tipranavir due to lack of exposure data.

The use of TYBOST is not recommended with darunavir 600 mg twice daily, fosamprenavir, saquinavir, or tipranavir. ( 1.2 , 5.4 ) Complex or unknown mechanisms of drug interactions preclude extrapolation of ritonavir drug interactions to certain TYBOST interactions. TYBOST and ritonavir when administered with either atazanavir or darunavir may result in different drug interactions when used with concomitant medications.

( 1.2 , 5.3 , 7 , 12.3 )

1.1Indications Adult Patients:

TYBOST is a CYP3A inhibitor indicated to increase systemic exposure of atazanavir or darunavir (once daily dosing regimen) in combination with other antiretroviral agents in the treatment of HIV-1 infection in adults [see Dosage and Administration (2.1) ]. Pediatric Patients: TYBOST is a CYP3A inhibitor indicated to increase systemic exposure of atazanavir or darunavir (once daily dosing regimen) in combination with other antiretroviral agents in the treatment of HIV-1 infection in pediatric patients weighing at least 14 kg [see Dosage and Administration (2.2) , and Drug Interactions (7.3) ].

1.2Limitations of Use

TYBOST is not interchangeable with ritonavir to increase systemic exposure of darunavir 600 mg twice daily, fosamprenavir, saquinavir, or tipranavir due to lack of exposure data. The use of TYBOST is not recommended with darunavir 600 mg twice daily, fosamprenavir, saquinavir, or tipranavir [see Warnings and Precautions (5.4) ]. Complex or unknown mechanisms of drug interactions preclude extrapolation of ritonavir drug interactions to certain TYBOST interactions.

TYBOST and ritonavir when administered with either atazanavir or darunavir may result in different drug interactions when used with concomitant medications [see Warnings and Precautions (5.3) , Drug Interactions (7) , and Clinical Pharmacology (12.3) ].

The concomitant use of TYBOST with atazanavir or darunavir and the following drugs is contraindicated due to the potential for serious and/or life-threatening events or loss of therapeutic effect [see Drug Interactions (7.3) and Clinical Pharmacology (12.3) ] . Alpha 1-adrenoreceptor antagonist: alfuzosin Antianginal: ranolazine Antiarrhythmic: dronedarone Anticonvulsants: carbamazepine, phenobarbital, phenytoin Anti-gout: colchicine Antimycobacterial: rifampin Antineoplastics: irinotecan These contraindications apply only to TYBOST coadministered with atazanavir Antipsychotics: lurasidone, pimozide Ergot Derivatives: dihydroergotamine, ergotamine, methylergonovine Herbal Products: St.