Partner 2 study extended for gay couples

Simon Collins, HIV i-Base

The second phase of the PARTNER Study aims to estimate the risk of HIV transmission in gay sero-discordant couples. [1]

To enrol, the HIV positive partner needs to be on ART with an undectectable viral load and the couple need to be sexually active and not always using condoms.

A total of 950 gay male (MSM) couples are needed for PARTNER 2 and currently 470 MSM couples are already participating in the first phase of the PARTNER study.

MSM couples already participating in PARTNER 1 will be encouraged to continue follow-up in PARTNER 2 until 2017.

Interim results presented at CROI 2014 reported no linked transmissions after 894 eligible couple-years of follow up and more than 44,500 exposures (half of which involved anal sex without a condom). [2]

The additional follow-up will provide similar confidence levels for the residual risk of HIV transmission for gay men compared to heterosexual couples.

UK sites for PARTNER 2

  • Chelsea and Westminster, London
  • Mortimer Market Centre, London
  • Royal Free Hospital, London
  • St. Thomas’s London
  • Western General Hospital, Edinburgh
  • Royal Sussex County Hospital, Brighton
  • Southmead Hospital, Bristol

New sites are still being sought for this second phase. For further information, please contact the study coordinator Tina Bruun:


  1. Partners of people on ART: a New Evaluation of the Risks (PARTNER), 2014-2017.
  2. Rodger A et al. HIV transmission risk through condomless sex if HIV+ partner on suppressive ART: PARTNER Study. 21st CROI, 3-6 March 2014, Boston. Oral late breaker abstract 153LB.

Links to other websites are current at date of posting but not maintained.