About The Study

This pilot study will gather data to help better understand the effects of two HIV medications (tenofovir and zidovudine) on infants’ health. Study researchers will examine if tenofovir exposure during an HIV-positive mother’s pregnancy affects the bones and kidneys of her uninfected infant, and if those effects are different from infants who were exposed to zidovudine. Infants will be assessed for any signs of mitochondrial toxicity and whether there is a difference in toxicity between tenofovir and zidovudine exposed infants.

About The Disease

Currently, use of tenofovir-based antiretroviral therapy regimens in pregnant women living with HIV to prevent transmission to the baby is not routinely recommended because of a lack of safety and efficacy information. However, more women are taking tenofovir-based regimens during pregnancy for different reasons (resistance, treatment of other infections, preference, etc.). Therefore, it is important to understand the effects tenofovir exposure may have on infants’ health.

Study Approach

Eligible participants will be asked some general health questions about the infant’s medical history and also the mother’s medical and pregnancy history. This information would include the mother’s age and race, as well as medications she was taking and blood work results.The study visits will occur when the infant is 1-month, 6-months and 18-months of age, and at the same time as regular clinic visits. At these visits, the following tests will be done:

  • Bone mineral density of the lumbar spine
  • X-ray to assess for rickets (a disease of the bones) (at 1-month and 18-months visits only)
  • The infant will have blood and urine samples taken for bone, kidney, and mitochondrial testing. Some of the blood tests will be the same ones that are done for a regular visit. The extra tests will be done when the child’s regular blood work is being done, and a small amount of extra blood will be taken. The total amount of blood drawn (for routine care and for the study) will be approximate 5 mL (or 1 teaspoon).
  • Growth parameters such as height and weight will be recorded.

Eligibility Requirements


  • Infants referred for follow-up testing after being born to an HIV-positive mother who was treated with antiretroviral therapy that included either TDF or AZT as the core NRTI drug
  • The infant’s guardian consents to study participation

Not Allowed

  • Known genetic or other predispositions for bone or renal disease (eg. osteogenesis imperfecta, congenital renal disease, etc.)
  • Prematurity less than 37 weeks gestation
  • Systemic steroid therapy

Principal Investigators

Here’s who is leading this study.

Can’t find what you’re looking for? Email ctninfo@hivnet.ubc.ca.

Dr. Jason Brophy

Co-Leader, Clinical Care and Management Core; Member, Steering Committee

Children’s Hospital of Eastern Ontario

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Participating Sites

Here’s where this study is being conducted.

The Children’s Hospital of Eastern Ontario

Ottawa, ON

Jen Bowes
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Oak Tree Clinic

Vancouver, BC

Site Principal Investigator: Dr. Ariane Alimenti; Research Coordinator: Evelyn Maan
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The Hospital for Sick Children

Toronto, ON

Site Principal Investigator: Dr. Ari Bitnun; Research Coordinator: Cheryl Arneson
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Montréal, QC

Site Principal Investigator: Dr. Valerie Lamarre; Research Coordinator: Silvie Valois
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