Program Supplement [International Conference on AIDS (14th: 2002: Barcelona, Spain)]

[ LBOR22 I
Nevirapine (NVP) during labor and in the neonate
significantly improves zidovudine (ZDV) prophylaxis for the
prevention of perinatal HIV transmission: results of PHPT-2
first interim analysis
Lallemant, Marc1, Jourdain, Gonzague', Le Coeur,
Sophie2, Mary, jean-Yves2, Koetsawang, Suporn', McIntosh,
Kenneth3, Ngo-Giang-Huong, Nicole', Kanshana,
Siriporn', Thaineua, Vallop' (Thailand; 2France; 3United States)
Background: ZDV starting at 28 weeks' gestation decreases
'in utero' transmission to 1-2%, but 4-5% 'intrapartum'
transmission still occurs. Adding NVP to ZDV during labor and
in neonates may further reduce intrapartum transmission.
Methods: Eligibility: ZDV prophylaxis from 28 wks' gestation or
as soon as possible thereafter (at least 2 wks), oral loading
dose during labor and 1 wk for infants (6 wks if mother <4 wks);
formula feeding. Multicenter, randomized, double-blind, 3-arm
study 1) NVP+ZDV mother/ NVP+ZDV infant; 2) NVP+ZDV
mother/Placebo+ZDV infant; 3) Placebo+ZDV
mother/Placebo+ZDV infant (Reference). Dosing: NVP mother
= 200 mg po at onset of labor, NVP infant = 6 mg po 48-72
hours after birth. Endpoint: HIV-infected infants (2 PCR+ on 2
samples); vs. uninfected (2 PCR- after 1 month).
Results: As of May 24, 2002, 1247 women have been enrolled,
ioo1100 have delivered. At the first interim analysis based on the
outcomes of the first 629 infants (May 2, 2002), the DSMB
recommended that we stop enrollment in the ZDV alone arm
because HIV transmission was significantly higher than in the
NVP+ZDV mother/ NVP+ZDV infant (stopping boundary:
P=o.ooo36), and that we continue the other 2 arms. Safety
data did not raise concerns. 48% of the women started ZDV
before/at 28 wks' gestation, 16% after 32 wks. ARV naive:
99%. Median baseline CD4+: 371/mm3 (18%<2oo); median log
viral load: 3.94. Median duration from study treatment intake
to delivery: 7 hours (13%<2 hrs); C-sections (non-elective):
21%. Infants: median time from birth to study treatment
intake: 48.5 hrs (98% (72 hrs).
Conclusion: Adding NVP during labor and in the neonate to
oral ZDV prophylaxis starting at 28 weeks' gestation or as soon
as possible thereafter significantly decreases the risk of HIV
perinatal transmission.
Sponsors: NIH Rol HD39615, USA; ANRS 1208 and IRD,
France; Ministry of Public Health, Thailand; BoehringerIngelheim (study treatment), Glaxo-Smith-Kline (ZDV), Roche
Diagnostics (DNA-PCR).
Corresponding author: Lallemant, Marc, 57/2 Faham Road, Soi
3, 50 00ooo Chiang Mai, Thailand, Tel: [phone],
Fax: [phone], Email: [email protected]
LBOR23
Does additional lubrication reduce condom failure?
A randomised controlled trial
GabbaMr Thomas, joanna, Gibbs, Alan
(United Kingdom)
Background: Condom failures potentially expose couples to
255M pregnancies & STIs each year worldwide, acting as a
disincentive to their use. Our large RCT investigated the impact
of additional spermicide on condom failure.
Method: Adult heterosexual condom users in stable relationships
were randomized using a crossover control design. Data were
collected by self-completion questionnaires. Failures were

classified using the recommended taxonomy. Main outcome
analyses used an intention to treat approach comparing couples'
proportional failure rates (to account for inter-subject variation)
during additional spermicide & control arms.
Results: 175 couples used 12,530 condoms, 145 completing
both trial arms with 67 clinical and 102 non-clinical failures.
Unadjusted overall failure rates were 44/6463 (0.7%) in the
additional lubrication arm & 113/6067 (1.9%) in the control
arm. There was a significant reduction in overall condom
failure rate for couples when using additional lubrication
(Wilcoxon signed ranks test Z = -2.36, P = 0.017), and fewer
clinical failures (Z= -1.9, P = 0.056). Couples with a history of
condom failure also had significantly fewer clinical failures
(Mann-Whitney Z = -2.18, P = 0.02). The only evidence of
adverse events was a mild risk of irritation with spermicide (13
v 2 subjects, McNemar's P = 0.013). Whilst some couples
preferred condoms alone, citing lubricant as an additional
interruption or messy, a significant proportion considered sex
with additional spermicide to be more pleasurable, and many
preferred it (Wilcoxon's Z = -4.2, P = 0.0005 for men, & -2.8, P
= 0.oo6 for women).
Conclusion: The low failure rate in this RCT concurs with recent
findings. Additional spermicide reduced condom failure, and
was popular with some users, but not others. Acceptable and
effective additional lubrication will boost condom popularity,
reduce failure and hence HIV transmission.
Corresponding author: Gabbay, Mark, Dept of Primary Care,
University of Liverpool, Whelan Building, Quadrangle,
Brownlow Hill, Liverpool L69 3GB, United Kingdom,
Tel: [phone], Fax: [phone],
Email: [email protected]
LBOR24
Joint Thai-US phase III trial of HIV prime-boost vaccines
Rerks-Nqarm Suhai1, Pitisuttithum, Punnee', Kitayaporn,
Dwip', Nitayaphan, Sorachai', Gurunathan, Sanjay2, Heyward,
William', Brown, Arthur', McNeil, John2
(' Thailand; 2United States)
Purpose: To describe the plan for initiating and implementing a
community-based, phase Ill efficacy trial of a prophylactic HIV
candidate vaccine combination in Thailand.
Methodology: Trial objectives: Determine whether this vaccine
combination 1) reduces the HIV infection rate by at least 50%,
and/or 2) results in decreased viral load and increased CD4
cell count in recipients who become infected with HIV, and 3) is
safe and well tolerated. Vaccines: Designed specifically for the
predominant circulating HIV of Thailand (CRFolAE). Prime -
recombinant canarypox ALVAC-HIV containing subtype B
Gag/Pro and Env-TM, and subtype E Env(R5) gene insertions
(vCP1521, Aventis Pasteur); Boost - monomeric gpl2os B(X4) +
E(R5) with alum (AIDSVAX B/E, VaxGen). Study population:
16,000ooo 20-30 year old Thai citizens from the communities of
Rayong and Chon Buri, Thailand. Study design:
Randomized(vaccine:placebo = 1:1), placebo-controlled,
double-blind, 3.5 year duration. Endpoints: Primary Efficacy -
HIV infection based on serological and nucleic acid testing;
Secondary Efficacy - HIV RNA and CD4 quantitation; Safety -
Adverse events and HIV risk-relevant behaviors. Projected start
date: December 2002
Discussion: Other than HIV vaccine candidates based on
envelope subunit proteins, recombinant canarypox is the only
candidate vaccine that has been assessed adequately to
transition into phase Ill testing. Combining both strategies

Program Supplement