Table 2.
Summary of key TFV oral and gel phase 2 and 3 safety and effectiveness studies for HIV prevention
| Phase 2/2b - Safety and Effectiveness Studies | |||||
|
FHI West Africa Study (9780)[60] Safety and Preliminary Effectiveness 2007 |
Ghana, Cameroon, Nigeria | Sexually active HIV- women, (N=936) |
Active: Daily TDF 300mg tablet Control: Daily placebo tablet |
Complete | No clinical or laboratory safety concerns Effectiveness not evaluable due to a small number of HIV infections observed. |
|
HPTN 059[64] Safety and acceptability 2008 |
US, India | Sexually active HIV- women, (N = 200) |
Active: Daily TFV 1% gel (N=50) Coital use: TFV 1% gel (N=50) Control: Daily placebo gel (N=50) Coital Use – placebo gel (N=50) |
Complete | No safety or acceptability differences or concerns between the arms |
|
CAPRISA 004[15] Expanded safety and effectiveness study 2010 |
South Africa | Sexually active HIV- women, (N = 889) |
Active: TFV 1% Gel (N=445) Control: Placebo Gel (N= 444) *BAT 24 |
Complete | 39% (95%CI: 6-60%) effective against HIV 51% (95%CI: 22-70%) effective against HSV-2[100] Higher gel adherence 54% effective in preventing HIV |
|
CDC 4323 [61, 62] Extended behavioural safety 2010 |
US | Sexually active HIV- MSM, (N=400) |
Active: Daily TDF 300mg tablet Control: Daily placebo tablet Group 1: Started at enrolment Group 2: Started 9 months after enrolment |
Complete | Preliminary analysis in July 2010 No serious safety concerns No increased risk in men taking PrEP compared to those not taking it. |
|
MTN 001[46, 66] Adherence and PK study 2011 |
US, South Africa, Uganda | Sexually active, HIV- women, (N=144) | Daily TFV 1% gel (N = 144) Daily TDF 300 mg tablet (N=144) Both (N=144) |
Complete | No safety or acceptability differences Tablet preferred in US women Vaginal tissue concentrations of TFV-DP-2log10 higher after vaginal dosing than oral dosing. |
|
MTN 003 (VOICE)[93] Safety and effectiveness study Initiated September 2009 |
South Africa, Zimbabwe, Uganda | Sexually active, HIV- women, (N=5000) |
Active: Daily TFV 1% gel (N=1000) Daily TDF 300mg tablet (N=1000) Daily TDF/FTC 300/200 mg tablet (N = 1000) Control: Placebo gel (N = 1000) Oral placebo tablet (N = 1000) |
Ongoing | Oral TDF arm stopped for futility September 2011 1% TFV gel arm stopped for fultility November 2011 No serious safety concerns Results expected in 2013 |
| Phase 3 - Effectiveness Studies | |||||
|
Partners PrEP study [12] Safety and effectiveness study Initiated May 2008 |
Kenya, Uganda | Sero-discordant heterosexual couples (N=4758) |
Active: Daily oral TDF tablet or Daily oral TDF/FTC tablet Control: Placebo tablet |
Ongoing | Preliminary analysis: safety concerns - SAEs similar in all arms. TDF effectiveness: 62% (95%CI: 34-78%) TDF/FTC effectiveness 73% (95%CI: 49-85%) |
|
CDC 4370 Bangkok Tenofovir Study Safety and effectiveness study Initiated June 2005 |
Bangkok | Injection drug users (N=2400) |
Active: Daily oral TDF tablet Control: Placebo tablet |
Ongoing | Results expected in 2012 |
|
FACTS 001 [76] Safety and effectiveness study including HSV-2 infection as a primary endpoint Initiated October 2011 |
South Africa | HIV-uninfected sexually active women (N=2200) |
Active: BAT 24* - TDF 1% Gel Control: HEC Placebo Gel |
Ongoing | Results expected in 2014 |
*
BAT24 Regimen - within 12 hours BEFORE coitus, as soon as possible within 12 hours AFTER coitus and up to TWO doses in a 24 hour period