Conditions: Healthy
Keywords: Healthy Subjects Pharmacokinetics study Pharmacokinetics of medications
Allocation: RANDOMIZED | Intervention model: FACTORIAL
Enrollment: 45
Healthy volunteers: yes

Brief summary:
To date, no study has investigated whether there is a drug interaction between the protease inhibitor fosamprenavir and the integrase inhibitor raltegravir. COL112775 is a randomized, open-label, 6-arm, 3-period, drug interaction study to assess steady-state plasma amprenavir (APV) and raltegravir (RTG) pharmacokinetics in 48 healthy, fasting, HIV-negative adults after administration of a 7-day regimen of RTG 400mg BID alone and after 14-day regimens of unboosted fosamprenavir (FPV) 1400mg twice daily (BID), FPV 700mg/RTV 100mg BID, or FPV 1400mg/ritonavir (RTV) 100mg once daily (QD) with and without concurrent RTG 400mg BID. Blood samples for drug concentration measurement will be collected over 12 hours at the end of each dosing period. Subjects will undergo a physical examination, complete blood count (CBC) with differential, HIV test, hepatitis B/C test, liver function test, renal function analysis, and lipid panel at screening, and all of these tests, except those for HIV and hepatitis B/C, will be repeated at follow-up post-study. Adverse events and adherence (by pill count and medication diary) will be assessed by the investigator/study personnel at the end of each dosing period

Detailed description:
This randomized, open-label, six-arm, three-period drug interaction study will recruit 48 healthy volunteers so as to obtain a minimum of 36 evaluable subjects at a single study center in the U.S. The study will have a screening visit, 3 treatment visits for pharmacokinetics (PK) sampling and a follow-up visit. The screening visit will be conducted within 30 days prior to receiving the first dose. Subjects will then be randomized into 1 of 6 treatment groups as shown below:

Cohort Size Period 1 Period 2 Period 3 Sample Days 1 to 7 Days 1-14 Days 1-14

A 8 RTG 400mg BID, FPV 1400mg BID, FPV 1400mg BID + RTG 400mg BID

B 8 RTG 400mg BID, FPV 1400mg BID + RTG 400mg BID , FPV 1400mg BID

C 8 RTG 400mg BID, FPV 700mg BID + RTV 100mg BID, FPV 700mg BID + RTV 100mg BID + RTG 400mg BID

D 8 RTG 400mg BID, FPV 700mg BID + RTV 100mg BID + RTG 400mg BID, FPV 700mg BID + RTV 100mg BID

E 8 RTG 400mg BID, FPV 1400mg QD + RTV 100mg QD, FPV 1400mg QD + RTV 100mg QD + RTG 400mg BID

F 8 RTG 400mg BID, FPV 1400mg QD + RTV 100mg QD + RTG 400mg BID, FPV 1400mg QD + RTV 100mg QD

Study subjects will enter the clinic in the morning prior to dosing in a fasting state and remain at the center for 12 hours following each dose. Fourteen to 21 days following completion of the third dosing period, study subjects will return to the clinic for follow-up assessment. The total duration of the study will be approximately 86 days from screening through follow up. Blood samples for drug concentration measurement of amprenavir (APV) and raltegravir (RTG) concentrations will be collected over 12 hours at the end of each dosing period (at 0 \[baseline\], 0.5, 1, 1.5, 2, 3, 4, 6, 8, and 12 hours post-dose). Subjects will undergo a physical examination, CBC with differential, HIV test, hepatitis B/C test, liver function test, renal function analysis, and lipid panel at screening, and all of these tests except those for HIV and hepatitis B/C will be repeated at follow-up post-study. Adverse events and adherence (by pill count and medication diary) will be assessed by the investigator/study personnel at the end of each dosing period. Evaluable patients will be required to have adhered to at least 95% of their study drug doses. Plasma APV concentrations will be analyzed using a validated high-performance liquid chromatography method with tandem mass spectrometric detection (HPLC/MS/MS) and plasma RTG concentrations by triple quadruple mass spectrometry. Plasma APV and RTG pharmacokinetic parameters measured will include maximum concentration (Cmax), time to maximum concentration (Tmax), minimum concentration (Cmin), and area under the concentration-time curve (AUC). All these parameters, except Tmax, will be log-transformed before statistical analysis. Analysis of variance, considering treatment as a fixed effect and subject as a random effect will be performed using Statistical Analysis Software (SAS), and assuming a treatment ratio for steady-state APV PK parameters as 1.0, the 90% confidence intervals will be within the range 0.81-1.24

Arms:
arm 1: Period 1-Raltegravir 400mg BID Period 2- Fosamprenavir 1400mg BID Period 3- Fosamprenavir 1400mg BID + Raltegravir 400mg BID arm 2: Period 1-Raltegravir 400mg BID Period 2-Fosamprenavir 1400mg BID + Raltegravir 400mg BID Period 3 Fosamprenavir 1400mg BID arm 3: Period 1-Raltegravir 400mg BID Period2- Fosamprenavir 700mg BID + Ritonavir 100mg BID Period 3- Fosamprenavir 700mg BID + Ritonavir 100mg BID + Raltegravir 400mg BID arm 4: Period 1-Raltegravir 400mg BID Period 2- Fosamprenavir 700mg BID + Ritonavir 100mg BID + Raltegravir 400mg BID Period 3-Fosamprenavir 700mg BID + Ritonavir 100mg BID arm 5: Period 1-Raltegravir 400mg BID Period 2- Fosamprenavir 1400mg QD + Ritonavir 100mg QD Period 3- Fosamprenavir 1400mg QD + Ritonavir 100mg QD + Raltegravir 400mg BID arm 6: Period 1-Raltegravir 400mg BID Period 2-Fosamprenavir 1400mg QD + Ritonavir 100mg QD + Raltegravir 400mg BID Period 3-Fosamprenavir 1400mg QD + Ritonavir 100mg QD

Interventions: intervention 1: Raltegravir intervention 2: Fosamprenavir intervention 3: Ritonavir
Intervention descriptions: intervention 1: 400mg BID intervention 2: 1400mg BID, 700 mg BID or 1400 mg QD intervention 3: 100 mg BID or QD

Protocol document: