a study on HIV/AIDS
Integrase is 1 of 3 HIV (Human Immunodeficiency Virus)-1 enzymes required for viral replication. Raltegravir is a drug that prevents integrase from working properly. This drug has been tested for safety and efficacy in adults, but this is the first study to examine raltegravir in children and adolescents. The purpose of this study was to determine the appropriate dose for raltegravir across the pediatric age range from 4 weeks to 18 years of age, by acquiring short and long term safety data, intensive and population pharmacokinetic (PK) data, and efficacy experience with raltegravir in HIV-infected children and adolescents.
A Phase I/II, Multicenter, Open-Label, Noncomparative Study of the International Maternal, Pediatric, Adolescent AIDS Clinical Trials (IMPAACT) Group to Evaluate the Safety, Tolerability, Pharmacokinetics, and Antiretroviral Activity of Raltegravir (Isentress, MK-0518) in HIV-1 Infected Children and Adolescents
Integrase is one of three enzymes necessary for HIV (Human Immunodeficiency Virus) replication. Integrase allows for the integration of HIV DNA (deoxyribonucleic acid) into the human genome. Raltegravir is a strong and selective inhibitor of HIV integrase. In adults, raltegravir has shown significant antiretroviral activity in clinical trials and is well tolerated. The purpose of this study was to determine the appropriate dose for raltegravir across the pediatric age range from 4 weeks (30 days) to 18 years of age, by acquiring short and long term safety data, intensive and population PK data, and efficacy experience with raltegravir in treatment-experienced, HIV-infected children and adolescents.
The study consists of two sequential Stages: I and II. The dose finding period of Stage I was intended to examine the pharmacokinetics and short term tolerability and safety of raltegravir in a limited number of participants to permit dose selection for further study in Stage II. The dose finding algorithm required a preliminary assessment of data from the first 4 patients of each cohort (termed a "mini-cohort"). Failure to meet PK targets required dose adjustments, contingent upon the mini-cohort's dose having met safety criteria, followed by reassessment of safety and PK data from the new mini-cohort dose. When a mini-cohort dose had passed both safety and PK criteria, further accrual to and an assessment of results from the full cohort could occur. Again, failure to meet PK targets required dose adjustments contingent upon the full cohort's dose having met safety criteria with subsequent PK and safety evaluation of data from a new cohort taking the new dose.
Chronic dosing, which includes Stage I extension (the period after Stage I dose finding) and Stage II (additional participants enrolled), was intended to provide longer term safety and antiviral activity data in a larger sample of participants. Participants accrued into Stage I and treated only at the dose ultimately selected for their cohorts were combined with those accrued into Stage II, where all patients received only the final selected doses for their respective cohorts. This group is denoted as the Final Dose Population, and results from this group are considered primary, since they reflect only the age-specific doses proposed for commercial use. The group with all participants exposed to raltegravir (at any dose) is denoted as the All Treated Population.
Stage I lasted for a minimum of 48 weeks, Stage II was for 48 weeks, and a long-term follow-up period will last for 5 years from initial exposure (i.e., 48 weeks of treatment plus 4 years of follow-up). Participants were stratified by age and assigned to one of six cohorts. Participants in Cohort I were between the ages of 12 and 18 years and received poloxamer film coated raltegravir tablets. Participants in Cohort IIA were between the ages of 6 and 11 years, weighed at least 25 kg, and received poloxamer film coated raltegravir tablets. Participants in Cohort IIB were between the ages of 6 and 11 years and received chewable raltegravir tablets. Participants in Cohort III were between the ages of 2 and 5 years and received chewable raltegravir tablets. Participants in Cohort IV were between the ages of 6 months (defined as 180 days) and 23 months and received oral granules for suspension. Participants in Cohort V were between the ages of 4 weeks (defined as 30 days) and 5 months and received oral granules for suspension.
Enrollment for Stage I of this study began with Cohort I and progressed to the other cohorts once preliminary dosage had been determined and safety data were reviewed. When this information had been determined for Cohort I, Cohorts IIA and IIB began enrollment. Once safety and dose data for these cohorts were reviewed, enrollment into Cohort III began. Once safety and dose data for Cohort III were reviewed, enrollment into Cohorts IV began and once safety and dose data for Cohort IV were reviewed, enrollment into Cohorts V began.
During Stage II of this study, participants took raltegravir at the dosage determined as safe and reaching PK targets based on the the Stage I data. The purpose of Stage II was to determine long-term safety of raltegravir once a safe dose meeting PK targets has been determined.
Participants whose Stage I dose was different from the dose determined for Stage II and who had not had individual dose adjustments because of extreme PK values had their raltegravir dose changed to the selected Stage II dose once it was determined. If individualizing the dose for participants in this manner resulted in a dose increase, these participants had an additional safety visit 4 weeks after the dose modification, and then continued on study visits with no further changes in the visit schedule.
There were at least 9 study visits for participants in this study, occurring during the 48-week raltegravir treatment period. For participants who completed 48 weeks of study and appeared to have benefited from receiving study drug, raltegravir will be provided until five years after initial raltegravir exposure. For participants who opt to continue on study-provided raltegravir, extended provision of drug will be implemented as part of a protocol extension involving visits every 4 months for five years after initial raltegravir exposure. Participants who do not continue on study-provided raltegravir will be followed with annual visits for five years after initial raltegravir exposure (i.e. 48 weeks of raltegravir treatment plus 4 years follow-up). At each visit, a physical exam, blood collection, and determination of treatment adherence will occur. At some visits, urine collection and Tanner staging will occur. Selected cohorts will undergo a taste evaluation at 1 of 2 visits. Participants aged 2 to less than 6 years of age were asked to participate in an additional PK substudy in which blood was collected two times over a 12-hour visit (or, if more convenient, this assessment may have been completed in 2 separate visits) in order to collect additional Cmin PK data. Participants were re-registered into the same cohort if a dose change was recommended.
On December 21, 2011, raltegravir was approved by the FDA (Food and Drug Administration) in combination with other antiretroviral drugs in children and adolescents ages 2 to 18 based on interim analysis of this study. The present results submission pertains to that interim analysis. The results present safety and efficacy results of complete Week 24 data (primary and key secondary endpoints) of Cohort I, IIA, IIB, and III participants from IMPAACT P1066, the Final Dose Population. By the date on which most of the data were frozen, 14Feb2011, all participants enrolled in Cohorts I, IIA, IIB, and III had Week 24 data (i.e., had either completed the Week 24 visit, or, for those who discontinued before Week 24, had the potential to have experienced the Week 24 visit). All participants enrolled in Cohorts I, IIA, and IIB had also completed (or had the potential to have experienced) the Week 48 visit. Note that as of this reporting, the study is ongoing with Cohorts I, IIA, IIB, and III in long-term follow-up and Cohorts IV and V, are in Stage II. There will be another results submission to report on the Cohort IV and Cohort V when these data are available.
HIV Infections Raltegravir Potassium
Open to people ages up to 18 years
for All Participants:
for All Participants:
Exclusion Criteria for Stage I Participants:
Exclusion Criteria for Stage II Participants Taking Atazanavir as Part of Their Background
© The Regents of the University of California