RITONAVIR

The pharmacokinetics of ritonavir have been studied in healthy volunteers and HIV-infected patients (CD 4 greater than or equal to 50 cells per μL). See Table 5 for ritonavir pharmacokinetic characteristics.

AbsorptionThe absolute bioavailability of ritonavir has not been determined. After a 600 mg dose of oral solution, peak concentrations of ritonavir were achieved approximately 2 hours and 4 hours after dosing under fasting and non-fasting (514 KCal; 9% fat, 12% protein, and 79% carbohydrate...

The activity of ritonavir as monotherapy or in combination with nucleoside reverse transcriptase inhibitors has been evaluated in 1446 patients enrolled in two double-blind, randomized trials. 14.1 Advanced Patients with Prior Antiretroviral Therapy Study 247 was a randomized, double-blind trial (with open-label follow-up) conducted in HIV-infected patients with at least nine months of prior antiretroviral therapy and baseline CD 4 cell counts less than or equal to 100 cells per μL. Ritonavir 600 mg twice-daily or placebo was added to each patient's baseline antiretroviral therapy regimen, whi...

The following adverse reactions are discussed in greater detail in other sections of the labeling. Drug Interactions [see Warnings and Precautions (5.1) ] Hepatotoxicity [see Warnings and Precautions (5.3) ] Pancreatitis [see Warnings and Precautions (5.4) ] Allergic Reactions/Hypersensitivity [see Warnings and Precautions (5.5) ] When co-administering ritonavir with other protease inhibitors, see the full prescribing information for that protease inhibitor including adverse reactions. The most ...

When co-administering ritonavir tablets with other protease inhibitors, see the full prescribing information for that protease inhibitor including contraindication information. Ritonavir tablets are contraindicated in patients with known hypersensitivity (e.g., toxic epidermal necrolysis (TEN) or Stevens-Johnson syndrome) to ritonavir or any of its ingredients. Ritonavir tablets are contraindicate...

The following have been observed in patients receiving ritonavir: The concomitant use of ritonavir and certain other drugs may result in known or potentially significant drug interactions. Consult the full prescribing information prior to and during treatment for potential drug interactions. ( 5.1 , 7.2 ) Toxicity in preterm neonates: Ritonavir oral solution should not be used in preterm neonates in the immediate postnatal period because of possible toxicities. A safe and effective dose of riton...

7 DRUG INTERACTIONS When co-administering ritonavir with other protease inhibitors (atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir), see the full prescribing information for that protease inhibitor including important information for drug interactions. Co-administration of ritonavir can alter the concentrations of other drugs. The potential for drug-drug interactions must be cons...