PreP Flashcards
What is the combination therapy used for PrEP?
Tenofovir (typically disoproxil + additional salt)
emtricitabine
Which trials are used/quoted in support of PrEP use?
iPrEx
PROUD
IPERGAY-OLE
How effective is PrEP for prevention of HIV infection?
iPrEx 44% reduction
PROUD 86% reduction
IPERGAY (extended) 97% reduction
Summarise iPrEx study?
phase 3
randomised, double blind, placebo-controlled
multi centre
DAILY dosing
MSM and trans male to female
South America, USA, Thailand, South Africa
HIV infections - TDF/FTC:placebo, 36:64
Summarise PROUD study?
phase 3 randomised open label multi centre DAILY dosing MSM and trans male to female sexual health clinics in England HIV infections - TDF/FTC:no PreP, 3:20
Summarise IPERGAY study?
phase 3 randomised, double blind, placebo-controlled multi centre ON DEMAND dosing MSM and trans male to female Canada and France HIV infections - TDF/FTC:placebo, 2:14
Of those with confirmed adherence to PrEP how many have acquired HIV?
3 case reports
What is the reason for HIV acquisition despite good adherence to PrEP?
2 of case reports had resistant virus
1 case report wild-type virus sensitive to tenofovir and emtricitabine
In which situation is PreP not recommended when HIV negative MSM have sex with HIV positive?
Partner has been on ART 6 months
and
viral load <200 (undetectable)
What is efficacy of PrEP dependent on?
Adherence
What side effects have been reported more commonly in those takin PrEP?
GI disturbance including nausea
Headache
What is the likelihood of a serious renal event on PreP?
Very low
Reversible (mostly)
What is the proportional effect on bone mineral density with PrEP?
Small net decrease 0.7-1%
No evidence of increased fracture risk
What effect does PrEP have on bacterial STI incidence?
Similar or Increase (dependent on study)
What is the rate of hepatitis C in MSM on PreP vs no PrEP?
4.8% vs 0.3-1.2%
What regimen of PreP can be used for heterosexual people?
DAILY
Summarise Partners PrEP study?
phase 3 randomised, double blind, placebo-controlled multi centre TDF vs TDF/FTC Daily dosing Heterosexual SERODIFFERENT couples Uganda and Kenya Efficacy - TDF 88% and TDF/FTC 91%
Summarise TDF-2 study?
phase 3
randomised, double blind, placebo-controlled
Daily dosing
Heterosexual men and women
Botswana
Concluded early ad underpowered
Efficacy - 62%; men > women (women 49%, men 80%)
Summarise FEM-PrEP study?
phase 3
randomised, double blind, placebo-controlled
multi centre
Daily dosing
Heterosexual WOMEN
Kenya, South Africa, Tanzania
No significant difference (likely due to low adherence)
Summarise VOICE study?
phase 2B
randomised, double blind, placebo-controlled
multi centre
TDF vs TDF/FTC vs vaginal tenofovir GEL
Heterosexual WOMEN
South Africa, Uganda, Zimbabwe
No significant difference (likely due to low adherence)
Which study is the most useful when considering PrEP in heterosexual men and women?
Partners PrEP study
What our virus does PrEP reduce the acquisition of?
HSV 2
When PrEP is used as a bridge to TasP for the seronegative partner how effective is it?
HIV incidence <0.05% per year vs >5% if not on PrEP
What are the differences between PrEP for heterosexual men and women and MSM?
MSM can have ON DEMAND or DAILY
Heterosexual DAILY only
Heterosexual can have tenofovir alone
What barriers to adherence to PrEP have been identified?
Perceived harm
Distinguishing between prevention and treatment
Social/community pressures/discouraged
What evidence is available for use of PrEP in pregnancy?
Partners PrEP - although stopped early pregnancy (average 35days)
2 USA clinics reported PrEP in pregnancy
Systematic review of TDF in HIV negative and chronic hepatitis B infection
Systematic review of TDF in HIV positive
Oral TDF-based PrEP appears SAFE in pregnancy, although no formal studies
Is PrEP detected in breast milk?
extremely low TDF
Higher levels of FTC (however 200-fold less than therapeutic dose)
aka VERY LOW concentrations TDF and FTC
Is there a change sexual behaviour that increases risk of STI in heterosexual people on PrEP?
Lack of data
What group of people at risk of HIV did the Bangkok Tenofovir Study review?
PWID
Summarise Bangkok Tenofovir Study?
phase 3
randomised, double blind, placebo-controlled
Daily dosing
TDF vs placebo
PWID (direct from drug treatment centres)
HIV infections - TDF:placebo, 17:33
What 3 drugs are typically used in chemise?
Crystal methamphetamine, ephedrine, GHB
What is BASHH/BHIVA recommendations on PrEP use in PWID?
Not recommended where needle exchange and opiate substitution programmes available
Consider on case by case
Chemsex relates to different demographic and should be explored
How much more likely are trans women to acquire HIV than the general population?
49 times higher
What factors contribute to trans women higher risk of HIV?
High level of discrimination Structural barriers to healthcare Violence Poverty High unemployment Housing instability