1. Adherence and Acceptability for PrEP formulations
Jessica Haberer, MD, MS
July 24, 2017

2. Conflicts of Interest
I have no conflicts to declare Grant funding: US National Institutes of Health, Bill and Melinda Gates Foundation, USAID Consultation: US National Institutes of Health, World Health Organization, Merck Stock: Natera

3. Overview Factors influencing adherence and acceptability
Multi-purpose technologies
Prevention-effective adherence
Perspective on adherence and effectiveness
Conclusions

4. Factors influencing prevention adherence
(Bekker, Lancet, 2015)

5. Adherence factors by PrEP formulation
Dosing
Daily
Periodic
On demand
Product formulations
Oral tablets
Vaginal or rectal microbicide
Vaginal rings
Depot injections
Unique adherence facilitators
Pair with daily routine (habit formation)
Infrequent dosing
Not a part of daily life
Less susceptible to stigma
Dosing only on cue (sex)
Unique adherence barriers
Fatigue
More susceptible to stigma
Remembering infrequent dosing
Discomfort (physical or psychological)
Being prepared for cue

6. Factors influencing acceptability
(Tolley, Antivir Res, 2013)

7. Choice is important for acceptability
Satellite sessions:
Next Wave of Prevention Options (AVAC)
Making Strides with Systemic PrEP
(Hall, JMIR, 2016)

8. Multi-purpose technologies
HIV prevention alone may not be a top priority
Motivation for adherence may increase with combined PrEP, contraception and/or prevention for other sexually transmitted infections (e.g., acyclovir for HSV)
Rings
Oral tablets
Depot Injections
Vaginal tablets
(Malcolm, BJOG, 2014; Boyd, Intl J Pharm, 2016; McConville, Eur J Pharm Biopharm, 2016)

9. Prevention-effective adherence
Prevention-effective adherence: alignment of adherence and risk for HIV acquisition (Haberer, AIDS, 2015)
PrEP use in this way can be high efficient: protection when needed with minimal individual burden and cost

10. Prevention-effective adherence
Requires knowledge of risk for HIV acquisition
Daily and periodic dosing should be assessed as “seasons”
On demand dosing needs on-going assessment; risk for inaccurate assessment mitigated through user friendly tools (e.g., Play Sure Kit)
All methods require good counseling and attention to acceptability
NYC Play Sure Kit

11. Perspective on adherence in prevention
Oral PrEP
Study
Adherence
Efficacy
2010
iPrEx
51% (plasma TFV)
44%
2012
Partners PrEP
82% (plasma TFV)
75%
2016
PROUD
Partners Demo Project
86% (days covered)
86% (plasma TFV)
86%
96%
Relevant factors
Clinical trial experience
Knowledge of efficacy
Self-selection/acceptability
Vaginal ring
2015
ASPIRE
The Ring Study
82% (plasma DPV )
84% (plasma DPV)
27%
31%
anticipated
HOPE, DREAM ?
(Grant, NEJM, 2010; Baeten, NEJM, 2012; McCormick, Lancet, 2016; Baeten, NEJM, 2017; Nel, NEJM 2017; Brown, IAS 2016 )

12. Perspective on adherence in prevention
Oral PrEP
Study
Adherence
Efficacy
2010
iPrEx
51% (plasma TFV)
44%
2012
Partners PrEP
82% (plasma TFV)
75%
2016
PROUD
Partners Demo Project
86% (days covered)
86% (plasma TFV)
86%
96%
Relevant factors
Clinical trial experience
Knowledge of efficacy
Self-selection/acceptability
Vaginal ring
2015
ASPIRE
The Ring Study
27-42% (residual ring DPV )
84% (plasma DPV)
65%
31%
anticipated
HOPE, DREAM ?
(Grant, NEJM, 2010; Baeten, NEJM, 2012; McCormick, Lancet, 2016; Baeten, NEJM, 2017; Nel, NEJM 2017; Brown, IAS 2016 )

13. Adherence and preferences
“…a less efficacious barrier (one that fails more often than another on each sexual encounter), if frequently used, might serve the public health as well or better than a more efficacious but less frequently used barrier, and could in the end play an important role in preventing transmission at the population level.”
(Am J Pub Health, 1990)

14. Conclusions Adherence and acceptability are multi-faceted
Choice matters and one size will not fit all
Multi-purpose technologies may increase acceptability and adherence
Prevention-effective adherence is the goal
Adherence evolves over time as experience with each PrEP product increases