HIV Part 3: Prevention & Treatment Flashcards
What is PrEP?
- Antiretroviral medications taken to PREVENT HIV
infection in HIV-negative individual - Tool for preventing HIV along with other HIV
prevention strategies (e.g., condoms, male
circumcision, behavioral risk reduction) - Does not prevent other STIs
More information about PrEP
- TDF 300 mg (Tenofovir disoproxil
fumarate) + FTC 200 mg (Emtricitabine) - Approved in Canada for HIV PrEP in 2016
(TAF/FTC approved Dec 2020) - Dose: 1 tablet daily (TDF/FTC) with or
without food [alternative dosing strategy
“PrEP on demand”] - Not recommended if CrCL < 60 mL/min
- PrEP not appropriate if unknown or
positive HIV status - Highly effective (>90%) if adherent
HIV Preventive Care Continuum
HIV-Negative Person
Behavioral Risk
Reduction
(ALONE)
Pre-Exposure
Prophylaxis
(PrEP)
Nonoccupational
Postexposure
Prophylaxis
(nPEP)
HIV-Positive Person
Treatment as Prevention
(TasP)
Behavioral risk reduction, ongoing support, and outreach
occurs throughout the continuum
So we ideally, you know someone’s HIV negative. We want to regularly screen, and and you have provide information about how to reduce risk and then be able t0 0ffer
prep. If if they maybe are
someone who’s higher at risk of acquiring HIV.
there’s also again post exposure, prophylaxis as an option, and then using treatment of of HIV as also a preventiontool,
Viral load suppresed w tx to prevent community transmission
Pharmacists’ Role in PrEP
How can I
access PrEP?
Can I take with my
other medications?
What if I miss a
dose?
How long can I
take PrEP?
Are there any
side effects?
Why do I have to
go for frequent
lab tests?
ELIGIBILITY CRITERIA FOR PREP –
GUIDELINES IN CANADA AND
ALBERTA
pretty much. All provinces now have publicly funded to prep for high risk groups
It’s important to have funding in place, because these drugs, even generics, I think, are both
$400 a month ish
PrEP eligibility guidelines
* MSM, Trans Women and Gender Diverse
People:
Condomless anal sex within last 6 months and any
of:
* Infectious syphilis or bacterial STI in past 12 months
* nPEP more than once
* Ongoing sexual relationship with HIV+ partner with
substantial risk of transmissable HIV (e.g. VL detectable
or HIV status unknown but from higher risk population –
MSM or PWID)
* HIRI-MSM risk score ≥ 11 (see resources)
HIRI-MSM
risk
assessment
tool
this was a a scoring system that was done in clinical trials.
if you’re younger. Or, again, if you had receptive anal sex in the last 6 months that would would get you on its own. A very high risk. Category
PrEP eligibility guidelines
* Heterosexual persons:
* People who inject drugs:
- Heterosexual persons:
– For HIV negative partner in an ongoing
relationship with HIV positive partner involving
condomless vaginal/anal sex where HIV positive
partner has substantial risk of transmissible HIV
(e.g. VL> 40 copies/mL) OR HIV status unknown
but from higher risk population (e.g. MSM, PWID) - People who inject drugs:
– sharing of injection drug use paraphernalia (e.g.,
needles, syringes, etc
How PrEP works
- PrEP prevents HIV from
establishing infection - Takes several days to
establish protective
levels of drug in
mucosal tissue to
prevent infection
– Rectal tissue – 7 days
– Vaginal tissue – 20 days
Crosses mucosal barriers starts to to infect local immune cells and start to replicate. And then it takes a few days, though, for then HIV to get into the blood and lymphatic system, and then start to spread and and seed throughout the body.
So prep. It starts working by preventing that infection to happen in the first.
even if someone had HIV and across the the mucus membranes. If you were taking medication that can interrupt that cycle that will prevent HIV from from continuing to infect immune cells and and getting more established early on.
it does take a bit of time to get absorbed and and to establish protective levels in in the tissues, that you might need it like rectal or vaginal tissues. So that’s just something to to be aware of that. People should be on it a minimum a week before high risk activities. But in terms of vaginal protection it can take even a bit longer than that.
Assessing Eligibility for PrEP
Individual is HIV negative (recent test) and is at high
risk of acquiring HIV infection
* No signs/symptoms of acute HIV in previous month
* No documented contraindications to FTC/TDF
- Other laboratory tests:
- Screening for HBV (vaccinate if susceptible), and HCV
- STI screening
- CBC, Scr, urinalysis at baseline
you need to confirm that the person is negative for HIV.
Requires hx taking to know if they are high risk
Lower risk - not funded by AB
No contra: renal fxn, severe osteoporosis
Starting PrEP
- Must be prescribed by designated prescriber (Alberta)
- Initial prescription x 30 days (no automatic refills)
- Discuss can take 7 days (or 20 days) to reach protective
concentrations - Adverse events:
- Common – headache, abdominal pain, flatulence
- Other – decreased renal function, decreased BMD
- Review if patient taking other drugs that may increase
risk of TDF renal toxicity - Reinforce/discuss strategies for adherence
Follow-up Assessment (at least every ___
months)
q3mo
* Screen to see if still eligible for PrEP (follow-up HIV &
STI testing every 3 months)
* Refill prescription for no more than 90 days
* Requests for refill extension – discuss with designated
prescriber (case by case basis)
* Assess adverse effects
* Assess and reinforce adherence
* Individuals of childbearing age/potential: pregnancy tests
this drug can be used in pregnancy. But again, just just wanting to do a pregnancy test as well, because again. both with respect to HIV risk, but also for prevention of transmission to a child. If if there was a exposure. So pregnancy testing is is recommended.
Which of the following would you not tell Shawn
regarding HIV pre-exposure prophylaxis (PrEP)?
a. PrEP reduces the risk of HIV by more than
90% if taken regularly
b. Once you are stabilized on PrEP, you only
need to get bloodwork every 6-12 months
c. It can take several days after starting PrEP to
have protective concentrations (in rectal or
vaginal tissues).
d. Side effects of HIV PrEP include decreased
bone mineral density.
B
Blood work is is typically recommended every 3 months.
You are working in an inner-city pharmacy and sustained a
needle-stick injury after giving a patient a flu shot. The source
patient has not been engaged in medical care and recent labs in
Netcare show a CD4 count of 124 cells/µL and HIV viral load of
48,000 copies/mL. What is the average risk of acquiring HIV
from a needlestick injury?
a. 0.3%
b. 3%
c. 10%
d. 25%
A
HCV is 3%
HBV 10%?
PEP – Post-exposure prophylaxis
What is it?
– Combination antiretroviral therapy (cART) given to someone who may have been exposed to HIV
– 2- or 3-drug regimens used to prevent acquisition of HIV infection
* Depends on type of exposure and infection status of source
- May be an occupational (e.g. needlestick injury) or nonoccupational exposure (e.g. sexual encounter, needlestick,
etc) - cART should be given as soon as possible, within 72 hours
- Refer to hospital emergency department for assessment if
someone has had an exposure in past 72 hours
these medications should be start started as soon as possible, and within 72 h. So again, that just comes down to we know the sooner you take it the more likely it’s going to interrupt replication, and more than 3 days after exposure is is unlikely to to have much benefit.
Basically the the best thing to do is, refer people to the the local emergency department for assessment. All ers in the province have post exposure, prophylaxis, kits with with drugs in the emergency department, and they would get started assessed. And then, if if they need criteria and get started on those.
And then often get referred to an infectious disease specialist for follow up, and an ongoing prescription
