VITA 2: The Effect of Phenytoin on the Pharmacokinetics of Nevirapine and the Development of Nevirapine Resistance

Sponsor

Radboud University Medical Center (Other)

Overall Status

Completed

CT.gov ID

NCT01187719

Collaborator

(none)

Enrollment

Locations

Arms

28.1

Duration (Months)

Patients Per Site

1.2

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The primary objective of this two-phase trial is as follows:

To determine the elimination half-life of NVP in HIV positive pregnant women receiving it as a single dose in labour in addition to the ZDV and 3TC with or without seven days phenytoin (pilot PK phase)
To determine NVP resistance in HIV positive pregnant women receiving it as a single dose in labour in addition to ZDV and 3TC with or without seven days phenytoin (main trial phase)

The secondary objectives of this two-phase trial are as follows:

To determine the safety of single dose nevirapine with seven days phenytoin as a part of ARV prophylaxis for PMTCT vs. single dose of nevirapine without phenytoin as a part of ARV prophylaxis for PMTCT
To determine the HIV status of the infant
To determine the safety of the ARV prophylaxis for PMTCT with seven days of phenytoin on the newborn

Hypothesis: phenytoin reduces the elimination half life of SD NVP and thereby decreases development of resistance to NVP in HIV positive pregnant Tanzanian and Zambian women.

Condition or Disease	Intervention/Treatment	Phase
HIV-infection Pregnancy Mother to Child Transmission	Drug: phenytoin	Phase 2

Detailed Description

This trial (VITA2) will be done with phenytoin as enzyme inducer to decrease the elimination half-life of NVP as it has also shown a significant difference in the elimination half-life of NVP in the ENVI study and side effects were also transient and mild. The guidelines for ARV prophylaxis for PMTCT has been changed to a more complex regimen. Therefore addition of phenytoin OD for 7 days after delivery will not complicate the regimen for the mother.

Tanzania and Zambia are among the countries in sub-Saharan Africa most affected by the HIV pandemic. In 2008, an estimated 85,000 children were living with HIV in Zambia and out of the 89,000 children born to HIV infected women, 28,000 are infected annually. In Tanzania, 140,000 children were living with HIV in 2007. Both countries use NVP alone or in combination with other drugs as ARV prophylaxis for PMTCT. Little data are available on the extent of NVP resistance in the Tanzanian, Zambian PMTCT setting. Moreover, there is no data available on the follow-up of mother-infant pair with particular focus on resistance to NVP and the infants HIV status. No studies have explored possibilities of reducing NVP resistance by use of an enzyme inducer.

This study seeks to the effect of phenytoin on the pharmacokinetics of NVP and the development of NVP resistance on SD NVP as part of the ARV prophylaxis for PMTCT. This intervention will be part of the VITA2 trial to test the hypothesis that phenytoin reduces the elimination half life of SD NVP and thereby decreases development of resistance to NVP in HIV positive pregnant Tanzanian and Zambian women.

Study Design

Study Type:

Interventional

Actual Enrollment :

66 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

None (Open Label)

Primary Purpose:

Prevention

Official Title:

The Effect of Phenytoin on the Pharmacokinetics of Nevirapine and the Development of Nevirapine Resistance After a Single Dose Nevirapine (VIramune®), Which is Part of ARV Prophylaxis for PMTCT in Moshi, TAnzania, and in Lusaka, Zambia (VITA2 Trial)

Study Start Date :

May 1, 2010

Actual Primary Completion Date :

Jun 1, 2012

Actual Study Completion Date :

Sep 1, 2012

Arms and Interventions

Arm	Intervention/Treatment
No Intervention: Control ARV prophylaxis for PMTCT follows national guidelines.
Experimental: phenytoin interaction ARV prophylaxis for PMTCT follows national guidelines + start phenytoin 184 mg (2 tablets of 92mg) OD at onset of labour and continue for seven days	Drug: phenytoin phenytoin 184 mg (2 tablets of 92mg) OD at onset of labour and continue for seven days

Arm

Intervention/Treatment

No Intervention: Control

ARV prophylaxis for PMTCT follows national guidelines.

Experimental: phenytoin interaction

ARV prophylaxis for PMTCT follows national guidelines + start phenytoin 184 mg (2 tablets of 92mg) OD at onset of labour and continue for seven days

Drug: phenytoin

phenytoin 184 mg (2 tablets of 92mg) OD at onset of labour and continue for seven days

Outcome Measures

Primary Outcome Measures

half-life time nevirapine [untill two weeks after NVP dosing]
blood samples will be taken <30 min after delivery, 24 hours after delivery, at day 3, at day 5, at day 7 and at day 14

Secondary Outcome Measures

NVP resistance [week 4 / week 6 after delivery]
resistance testing at week 4 or week 6 after delivery (and NVP dosing).
safety of co-administration phenytoin and NVP [entire trial]
Adverse events will be collected during the entire trial (for both mother and child).
HIV status of the newborn [week 6 after birth]
HIV status of the newborn will be assessed at week 6 after birth.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

Female

Accepts Healthy Volunteers:

Inclusion Criteria:

HIV-infected as documented by positive HIV antibody test
Antiretroviral naïve
Starting ARV prophylaxis from 28th weeks of gestation or at least 4 weeks before delivery
Not intending to relocate out of the area for the duration of study participation
Willingness of subject to adhere to follow up schedule (note: this is more intensive for the pilot PK phase)
Ability and willingness of subject to give written consent
Pregnant women aged 18 years and above
Willing and able to regularly attend the antenatal clinic

Exclusion Criteria:

Serious illness that requires systemic treatment or hospitalization
Use of concomitant medication, which interferes with the ARV prophylaxis for PMTCT or phenytoin
Any condition that in the opinion of the investigator would compromise the subjects' ability to participate in the study
Previously treated for HIV infection with antiretroviral agents, including ARV prophylaxis for PMTCT
Inability to understand the nature and extent of the trial and the procedures required
CD4 count <350 cells/µl because such a patient is eligible for HAART