Is on-demand PrEP a suitable tool for MSM who practice chemsex Is on-demand PrEP a suitable tool for MSM who practice chemsex? Results from a sub-study of the ANRS-IPERGAY trial Roux P1, Fressard L1, Suzan-Monti M1, Chas J2, Capitant C3, Meyer L3, Tremblay C4, Molina JM5, Pialoux G2, Spire B1 1INSERM UMR912 – SESSTIM, Marseille; 2Hôpital Tenon, Paris; 3INSERM SC10, Le Kremlin-Bicêtre; 4Université de Montréal; 5Hôpital Saint-Louis, Paris

No conflicts of interest to declare. Conflict of Interest No conflicts of interest to declare.

Context Chemsex - the use of psychoactive substances during sexual encounters : a growing concern among MSM Stuart, HIV Nursing, 2013; McCall, 2015, BMJ Main reasons for practicing chemsex reported by MSM Weatherburn, 2017, STI to increase confidence, disinhibition and stamina to enhance sexual arousal and eroticism Main drugs involved : crystal meth, GHB/GBL, cathinones Psychostimulants, empathogens, hallucinogens High potential of addiction

Context One very risky element in chemsex is “slamming” = drug injection before sex Foureur, 2015, AIDES Many negative consequences of chemsex : related to drug use but also to sexual risk behaviors Bourne, 2015, IJDP Including HIV transmission ANRS-Ipergay trial : efficacy of on-demand PrEP in preventing HIV transmission among MSM Molina, 2015, NEJM; Molina, 2017, Lancet HIV Question: Is PreP a suitable tool to prevent HIV transmission in MSM who practice chemsex ?

Methods (1) ANRS IPERGAY : a double-blind RCT conducted in France and Canada providing sexual activity-based antiretroviral prophylaxis (PrEP) Inclusion criteria: HIV- males or transgender women who have sex with men aged 18 years or older at high risk of HIV Data collection: online questionnaire every 2 months sociodemographic characteristics alcohol and recreational drug use sexual behaviors PrEP adherence during the most recent sexual encounter

Methods (2) Present sub-study : open-label extension N=331 participants, 1,657 visits Median[IQR] follow-up=10 [9-11] months Objectives To characterize chemsexers (being under the effect of a psychoactive drug during most recent sexual encounter) To study the association between chemsex and PrEP use (having used PrEP during most recent sexual encounter) Statistical analyses: logistic regression using a GEE model

least once during follow-up Results (1) Characteristics of participants : chemsex versus no chemsex during follow-up Participants (N=331) Practiced chemsex at least once during follow-up p† No N=236 (71%) Yes N=95 (29%) % or mean (SD) Age 36 (10) 36 (9) Educational level > high school 74.2 81.1 Active employment 86.9 85.2 Anxiolytic consumption 19.5 40.0 *** Antidepressant consumptiona 14.8 14.7 Recent depressiona 20.8 22.1 Sensation Seeking Score (BSSS-4)b 11 (4) 13 (4) Participation in prevention activitiesa 37.7 39.0 Practiced slamming at least once during follow-upc 1.9 23.5 Number of sexual encounters (previous 4 weeks)d 11 (11) 20 (24) † Chi² tests for categorical variables, t-test for continuous variables. *** p≤0.001 a during the previous 12 months b 10 missing values c 39 missing values d Reported at most recent assessment; 2 missing values Abbreviations: BSSS-4 = Brief Sensation Seeking Scale, as per Stephenson et al., 2003.

Results (2) Factors associated with chemsex at most recent sexual encounter  Visits (N=1657) Practiced chemsex during most recent sexual encounter p† No N=1400 (84%) Yes N=257 (16%) % or mean (SD) Chemsex with one partner (vs. multiple partners)a - 75.9 Psychoactive substances involved a GHB/GBL 51.4 Mephedrone/cathinone/PDPV/NRJ3/4MEC 45.9 Amphetamine-like substances (ecstasy/methamphetamines) 24.5 Cocaine 22.2 Type of partner *** Main partner 33.6 12.1 Casual partner 59.4 63.8 Multiple partners 6.9 24.1 High-risk HIV exposure : condomless anal sexb 68.4 79.6 Hardcore sexual practices (fisting, sadomasochistic practices)c 7.1 33.5 HIV transmission risk perception [0;10] 3 (3) 4 (3) PrEP used 80.1 94.1 † Chi² test for categorical variables, t-test for continuous variables. *** p≤0.001  a Among 257 visits reporting chemsex (195 with one, 62 with multiple partners) b 29 missing values c 16 missing values d 19 missing values

Results (3) Factors associated with PrEP use at most recent sexual encounter Results from GEE multiple logistic regression, n=331 participants, 1619 visits  aOR [95% CI] p† Age (ref. 19-29) 30-42 2.3 [1.3;4.1] ** 43-61 4.3 [2.2;8.6] *** Educational level > high school (ref. No) 0.6 [0.3;0.96] * Active employment (ref. No) 1.5 [0.9;2.7] Recent depression (ref. No) 0.6 [0.3;0.95] At most recent sexual encounter: Type of partner (ref. Main partner) Casual partner 7.8 [5.3;11.6] Multiple partners 29.2 [8.6;98.4] Sexual practices (ref. Oral sex) Insertive anal sex and/or oral sex 1.4 [0.8;2.4] Receptive anal sex and/or insertive anal sex and/or oral sex 1.2 [0.7;2.0] High-risk HIV exposure: condomless anal sex (ref. No) 1.5 [0.9;2.4] HIV transmission risk perception [0;10] 1.1 [1.0;1.2] Chemsex practice (ref. No) 2.2 [1.1;4.6] † p-values for the parameters estimates. * p≤0.05 ** p≤0.01 *** p≤0.001. Abbreviations: aOR [95%CI] = adjusted odds-ratio [95% confidence interval]

Discussion (1) Chemsex practice is associated with PrEP use No significant difference between chemsexers and non-chemsexers regarding sociodemographic characteristics However, chemsexers have a more vulnerable psychological profile: anxiolytic consumption and higher scores on sensation-seeking scale

Discussion (2) Chemsex associated with: sex parties/casual partners, high-risk/hardcore practices but higher HIV transmission risk perception PrEP is a suitable tool to reduce HIV transmission in chemsexers Access to PrEP is an opportunity to provide other prevention interventions and comprehensive care for chemsexers

Acknowledgments Participants Study and Peer Counselors Trial Scientific committee DSMB ANRS Staff INSERM SC10-US19