Evaluating the Safety and Pharmacokinetics of VRC01, VRC01LS, and VRC07-523LS, Potent Anti-HIV Neutralizing Monoclonal Antibodies, in HIV-1-Exposed Infants

Open-Label, Dose-Escalating, Phase I Study to Determine Safety and Pharmacokinetic Parameters of Subcutaneous (SC) VRC01, VRC01LS, and VRC07-523LS, Potent Anti-HIV Neutralizing Monoclonal Antibodies, in HIV-1-Exposed Infants

The purpose of this study was to assess the safety and pharmacokinetics (PK) of three monoclonal antibodies, VRC01, VRC01LS, and VRC07-523LS, in HIV-exposed infants who are at increased risk of mother-to-child HIV transmission.

VRC01, VRC01LS, and VRC07-523LS are anti-HIV neutralizing monoclonal antibodies that may help prevent mother-to-child transmission of HIV. This study enrolled HIV-infected mothers who were at increased risk of passing HIV on to their children. The purpose of this study was to assess the safety and PK of VRC01, VRC01LS, and VRC07-523LS in HIV-exposed infants.

This study enrolled mother-infant pairs into five dose groups. Infants enrolled in Dose Group 1 and Dose Group 2 received a single VRC01 injection less than 72 hours after birth. Infants in Dose Group 3 received a VRC01 injection less than 5 days after birth, followed by VRC01 injections monthly for at least 6 months and no more than 18 months, while breastfeeding.

Dose Groups 4 and 5 each enrolled infants into two cohorts: Cohort 1 (non-breastfeeding) or Cohort 2 (breastfeeding). Infants in Dose Group 4, Cohort 1 received a single VRC01LS injection less than 72 hours after birth. Infants in Dose Group 4, Cohort 2 received an initial VRC01LS injection no longer than 5 days after birth, and a second VRC01LS injection at Week 12 if they were still breastfeeding. Infants in Dose Group 5, Cohort 1 received a single VRC07-523LS injection less than 72 hours after birth. Infants in Dose Group 5, Cohort 2 received an initial VRC07-523LS injection no longer than 5 days after birth, and a second VRC07-523LS injection at Week 12 if they were still breastfeeding.

The mothers did not receive any VRC01, VRC01LS, or VRC07-523LS injections. At study entry, all mothers underwent a medical history review and a blood collection, and then the study ended for the mothers.

Infants in Dose Groups 1 and 2 attended study visits at days 0, 1, 3, 7, 14, 28 and at weeks 8, 16, 24, and 48. Infants in Dose Group 3 attended study visits at days 0, 1, 14, 28 and at weeks 8, 12, 16, 20, 24, and every 4 weeks until cessation of breastfeeding or week 72, then at weeks 84 and 96. Infants in Dose Group 4 attended study visits at days 0, 1, 14, 28 and at weeks 8, 12, 24, 36, 48, 60, 72, 84 and 96, with additional visits at weeks 14 and 16 for Cohort 2 participants. Infants in Dose Group 5 attended study visits at days 0, 1, 3, 7, 14, 28 and at weeks 8, 12, 24, 36, 48, 60, 72, 84 and 96, with additional visits at weeks 14 and 16 for Cohort 2 participants. Visits included a medical history review, physical examination, blood collection, and oral fluid collection.

Maternal Inclusion Criteria:

• HIV infection
• Greater than or equal to 18 years of age
• Able and willing to provide signed informed consent for herself and her infant

Maternal Exclusion Criteria:

• Prior participation in any HIV-1 vaccine trial
• Receipt of any other active or passive HIV immunotherapy or investigational product during this pregnancy. (Note that administration of Food and Drug Administration [FDA]-approved antiretroviral (ARV) drugs when used to treat disease or prevent mother-to-child transmission were not considered investigational.)
• Documented or suspected serious medical illness or immediate life-threatening condition (other than HIV infection) in the mother that may have interfered with the ability to complete study requirements, as judged by the examining clinician

Infant Inclusion Criteria:

• Born to an HIV-1-infected woman who met all maternal inclusion/exclusion criteria listed above

• Gestational age, by best obstetrical, ultrasound, or infant exam, greater than or equal to 36 weeks

• Birth weight greater than or equal to 2.0 kg

• Allowable infant age at the time of enrollment was dependent on the Dose Group and Cohort:

  • Dose Groups 1, 2, 4 and 5 (Cohort 1): Less than 72 hours of age, and anticipated availability to receive VRC immunization at less than 72 hours after birth.
  • Dose Groups 3, 4 and 5 (Cohort 2): Less than or equal to 5 days of age, and anticipated availability to receive VRC immunization no more than 5 days after birth.

• At increased risk of HIV acquisition defined as documentation of one or more of the following risk factors:

• Dose Groups 1, 2, 4 and 5 (Cohort 1), only:

  • Mother received no antiretroviral therapy (ART) during pregnancy or mother began or reinitiated ART (after an interruption of greater than 14 days), during the third trimester of pregnancy; or

  • Mother with any detectable viral replication (HIV RNA above the limit of detection) at last measurement prior to delivery determined within 30 days of delivery; or

  • Prolonged rupture of membranes (greater than 12 hours); or

  • Mother with documented 2-class resistant HIV infection, which may have included historical documentation of lack of response

    • Women who had a documented history of virologic failure while on non-nucleoside reverse transcriptase inhibitors (NNRTIs) but who had no resistance testing at the time of viral failure were considered to have NNRTI-documented resistance.

• Dose Groups 3, 4 and 5 (Cohort 2), only (African sites):

  • Mother intended to breastfeed

Infant Exclusion Criteria:

• Receipt of any other active or passive HIV immunotherapy or investigational product other than the study vaccine (Note: Infant prophylaxis with any licensed ARV drugs clinically prescribed to prevent mother-to-child HIV transmission were not considered investigational.)

• Receipt of or anticipated need for blood products, immunoglobulin, or immunosuppressive therapy. This included infants who required hepatitis B immunoglobulin (HBIG) but did not require exclusion of infants who received hepatitis B vaccine in the newborn period.

• Documented or suspected serious medical illness, serious congenital anomaly, or immediate life-threatening condition in the infant that may have interfered with the ability to complete study requirements, as judged by the examining clinician

• Any requirement for supplemental oxygen beyond 24 hours of life or requiring supplemental oxygen at the time of the VRC01, VRC01LS, or VRC07-523LS dose

• Baseline laboratory results:

  • Hemoglobin less than 12.0 g/dL
  • Platelet count less than 100,000 cells/mm^3
  • Absolute neutrophil count: for infants less than or equal to 24 hours old, less than 4,000 cells/mm^3; for infants greater than 24 hours old, less than 1,250 cells/mm^3
  • Serum glutamic pyruvic transaminase (SGPT) greater than or equal to 1.25 times upper limit of age adjusted normal

• Dose Groups 1, 2, 4 and 5 (Cohort 1), only: Infant was breastfeeding at time of enrollment or mother had indicated an intention to initiate breastfeeding. Note: if a child was breastfed prior to known maternal diagnosis (in the case of a woman diagnosed in the intrapartum period), the child was still eligible as long as breastfeeding was stopped by the time the child was enrolled and there was no plan to resume breast milk feeding.