1 Tenofovir Disoproxil Fumarate (TDF) Pharmacokinetics (PK) with Daily Dosing in the First Week of Life (HPTN 057) Karin Nielsen-Saines*, Mark Mirochnick, Newton Kumwenda, Esau Joao, Regis Kreitchmann, Jorge Pinto, Breno Santos, Teresa Parsons, Taha Taha, Lynne Mofenson, Paul Sato, Brian Kearney, and Mary Glenn Fowler for the HPTN 057 Protocol Team Washington, D.C. July 23, 2012 HPTN 057 TUAB0201

Background  Alternatives to perinatal single dose NVP are needed for HIV PMTCT purposes.  Tenofovir (TFV): Is highly effective in protecting newborn macaques against SIV infection with no major toxicity and no development of resistance Is available as a pro-drug (tenofovir disoproxil fumarate - TDF) in an oral tablet for maternal dosing and powder for oral suspension for infants  Can we develop a simple TDF regimen for use in place of NVP in pregnant women during labor and in the newborn? 2 HPTN 057

Study Design and Objectives  HPTN 057: A prospective, phase I study of the PK and safety of TDF administered to HIV infected pregnant women in labor and to their infants.  Primary objectives: To evaluate the pharmacokinetics, safety and tolerance of intrapartum/neonatal TDF in HIV-infected women and their infants.  Secondary objectives: T o evaluate the effect of single dose TDF on maternal HIV-1 RNA levels, evaluate viral resistance to TDF in women and infants, determine infection status of infants & measure TDF concentration in amniotic fluid and breast milk following maternal exposure. HPTN 057

PK target and sites  PK Goal: Maintain infant TDF concentration throughout the first week of life above 50 ng/mL, the mean trough TDF concentration in adults receiving chronic dosing with TDF.  Study sites: Malawi and Brazil  Malawi College of Medicine, Blantyre, Malawi  Univ. Federal de Minas Gerais, Belo Horizonte, Brazil  Irmandade Santa Casa da Misericordia, Porto Alegre, Brazil  Hospital Nossa Senhora da Conceiçao, Porto Alegre, Brazil  Hospital dos Servidores do Estado, Rio de Janeiro, Brazil  Study Strategy : Maternal/infant TDF dosing in addition to local PMTCT standard of care. HPTN 057

Study cohorts (n = 122 mother-infant pairs enrolled) Cohortn Maternal TDF Dosing (in labor) Infant TDF Dosing mg x1None 220None 4 mg/kg within 12 hours of birth, day 3 and day mg x1 6 mg/kg within 12 hours of birth, day 3 and day mg x 16 mg/kg daily x 1 week HPTN 057

Patient Characteristics cohort 4  33 Mother/infant pairs enrolled/followed for 12 mo 16 in Malawi, 17 in Brazil  Route of Delivery: 21 vaginal, 12 cesarean section  Median maternal delivery weight (kg): 66 kg, range: kg  Median time between maternal dose and delivery: 4.5 hrs, range: ( ) hrs  Median birth weight: 3.1 kg, range: 2.1 – 4.2 kg HPTN 057

Cord Blood and Maternal Delivery TDF Concentrations Cord Blood61 ng/mL (69.3%) Cord Blood TDF > 50 ng/mL24/31 (77%) Maternal Delivery Concentration108 ng/mL (76.1%) Cord Blood/Maternal Delivery Ratio0.55 (64.0%) Geo mean (CV%) or #/n (%) HPTN 057

Infant TDF PK Results Predose (ng/mL) % with Predose >50 ng/mL Tmax (hr) Cmax (ng/mL) AUC (ng*hr/mL) t½ (hr) Initial Dose 29 (6.7%) 45% 6.9 (54.8%) 288 (49.9%) (37.6%) 13.2 (80.1%) Dose (84.5%) 100% 2.3 (99.2%) 336 (40.5%) (37.4%) 14.5 (45.0%) Dose 7 79 (77.2%) 84% 3.4 (84.6%) 221 (66.1%) 3061 (49.0%) 14.6 (96.1%) Geo mean (CV%) or % HPTN 057

Amniotic fluid concentrations of TDF  Amniotic fluid was obtained from women who underwent elective C-section for obstetrical reasons.  24 paired amniotic fluid - serum specimens were obtained from 3 of the study cohorts. The drug achieved effective amniotic fluid concentrations in the majority of subjects, with highest levels hrs post-dosing. 9 HPTN 057 Geo mean 168 ng/ml, coeff variation: 72%

Safety of TDF  All mothers and infants tolerated TDF well.  Mild/moderate abnormal laboratory results according to the DAIDS Toxicity Tables were common but appeared representative of local site background values in HIV infected women and their newborns.  No severe or life-threatening adverse events or deaths were assessed by the Protocol Safety Review Team as possibly, probably, or definitely related to TDF.  An HPTN Study Monitoring Committee reviewed safety and toxicity and noted no safety concerns.  1 of 33 infants (3%) in cohort 4 was found to be HIV- infected. HIV PCR was + at birth (in utero infection). In total 5 of 122 infants were infected in 057 (4.1%) HPTN 057

Summary/ Conclusions This regimen of a single maternal TDF dose of 600 mg during labor and a daily TDF dose of 6 mg/kg to the infant during the 1 st week of life:  Was safe and well tolerated.  Achieved cord blood TDF concentrations above 50 ng/mL target in most infants.  Maintained infant TDF concentrations above 50 ng/mL during the first week of life. 11 HPTN 057

Mothers and children who enrolled in the study. Pharmaceutical :Gilead Sciences: James Rooney, Brian Kearney Study Sponsors: NIAID: Paul Sato and Sheryl Zwerski Eunice Kennedy Shriver NICHD: Lynne Mofenson, George Siberry DAIDS Pharmaceutical Branch: Ana Martinez, Scharla Estep, Eva Purcell (in memoriam) Study Coordination: FHI: Kathleen George, Melissa Allen Scharp: Lynda Emel, Elizabeth Brown, Molly Swenson Institutions and Investigators: Boston University: Mark Mirochnick UCLA: Karin Nielsen, Yvonne Bryson Johns Hopkins University, Baltimore: Taha Taha Malawi College of Medicine, Blantyre: Newton Kumwenda, George Kafulafula (in memoriam), Robin Broadhead Federal University of Minas Gerais, Belo Horizonte: Jorge Pinto, Fabiana Kakehasi Irmandade Santa Casa de Misericordia, Porto Alegre: Regis Kreitchmann, Debora Coelho Hospital dos Servidores, Rio de Janeiro: Esau C. Joao, M. Leticia Santos Cruz, Leon Sidi Hospital Nossa Senhora da Conceicao, Porto Alegre: Breno Santos, Rita Lira, Rosana Fonseca CDC: Mary Glenn Fowler HPTN Central Lab: Paul Richardson, Susan Eshelman HPTN PK network: Teresa Parsons 12 Acknowledgments…. HPTN 057