HIV Prevention

Question 1

What is treatment as prevention (TasP)?

Answer 1

Individuals with HIV who are on antiretroviral therapy (ART) and maintain an undetectable viral load cannot sexually transmit the virus to others, and are less likely to transmit via vertical transmission or with contaminated drug paraphernalia or hygiene items

Question 2

What are some harm reduction programs to be aware of? (6)

Answer 2

1. Opioid Agonist Therapy programs
2. Safer drug use education, equipment, and supply
   - syringes, needles, cookers, pipes, filters
   - safer drug supply
3. Safe consumption or injection sites
4. Safer sex education & equipment
   - Condoms
   - Sero-positioning - e.g., person with HIV takes receptive position during unprotected anal sex as risk of tranmission is lower
5. Housing programs
6. Regular STI testing & follow-up

Question 3

What is pre-exposure prophylaxis (PrEP)? (3)

Answer 3

1. PrEP is an HIV prevention strategy to reduce the risk of acquiring HIV
2. Taken by HIV-negative individuals considered at risk of infection.
   - Truvada (Tenofovir Disoproxil Fumarate + Emtricitabine) or Descovy (Tenofovir Alafenamide + Emtricitabine)
3. PrEP reduces the risk of acquiring sexually transmitted HIV by more than 90% if taken as prescribed and by at least 74% among persons who inject drugs (PWID)
   - Adherence is key!

Question 4

What are the 2 PrEP regimens?

Answer 4

1. Truvada 1 tablet once daily
   - Descovy not covered generally, would present an option for those with renal insufficiency
2. “On demand”- Truvada 2 pills 2-24 hrs prior to first sexual exposure followed by 1 pill daily until 48 hrs after last sexual activity “2-1-1”
   - Trials only support use in MSM

Question 5

What are the baseline investigations needed for PrEP? (7)

Answer 5

1. HIV status = Contraindicated if client is HIV +
   - Baseline HIV testing with confirmatory test (blood test)
   - If client recent high-risk exposure, repeat blood test after 14-21 days
2. Hepatitis A, B, and C status
   - if positive for Hepatitis B or C, refer to ID specialist
3. Baseline STIs, as appropriate = if positive, treat accordingly
4. Pregnancy, if appropriate
5. CBC, renal panel including eGFR, urinalysis
6. Comorbidities such as renal dysfunction, mental health, substance use disorder
7. Vaccination status = may offer hepatitis A and hepatitis B vaccine if non-immune, & HPV if unvaccinated

Question 6

Who is covered for PrEP?

Answer 6

Truvada available to all Saskatchewan residents with no cost

Question 7

What are the common side effects of Truvada? (2)

Answer 7

1. GI symptoms, headache, fatigue -> more common in on-demand regimen vs. daily
2. Renal toxicity – usually reversible upon discontinuation, reduction in bone mineral density in first ~6 months

Question 8

What are some drug interactions of Truvada to be aware of?

Answer 8

Avoid nephrotoxic agents e.g., NSAIDS, aminoglycosides

Question 9

Can PrEP be used in pregnancy?

Answer 9

Yes - only Truvada once daily for pregnancy/lactation

Question 10

When should PrEP not be used? (3)

Answer 10

1. Unknown HIV status
2. HIV+
3. Renal function CrCL <60 mL/min

Question 11

Can pharmacists prescribe PrEP?

Answer 11

Yes, but only with a collaborative prescribing agreement

Question 12

What should we be educating patients about with PrEP? (6)

Answer 12

1. Benefits
2. Adherence is vital for effectiveness and needs to be stressed at baseline and review at subsequent visits
3. If utilizing PrEP on-demand, ensure clients understand instructions
4. Tell clients that 7 days is required to meet effective concentrations (in anal and vaginal tissues) when PrEP taken once daily (some controversy around whether it takes 7 or 20 days in cervicovaginal tissues)
5. PrEP does NOT prevent against other STBBIs/STIS
6. Side effect expectation and management -> improves adherence

Question 13

How often to follow up after PrEP?

Answer 13

At one month, then every 3 months via telephone

Question 14

What to know about PrEP discontinuation? (5)

Answer 14

1. If indication not present or client wishing to discontinue treatment:
2. In MSM or TGW:
   - Discontinue PrEP 2-28 days after last exposure
3. In heterosexuals or PWID:
   - Discontinue PrEP 28 days after last exposure
4. On demand:
   - As per regimen, take last tablet 48 hours after last exposure
5. Recommended to repeat HIV serology 8-12 weeks after discontinuation

Question 15

What is post-exposure prophylaxis (PEP)? (2)

Answer 15

1. Involves the use of HIV medications in an HIV negative person who may have been exposed to HIV to prevent transmission.
2. HIV PEP should start as soon as possible, must be started within 72 hrs of exposure

Question 16

What is PEP treatment? (3)

Answer 16

1. The adult PEP kit in Saskatchewan includes 5 day supply of:
   - Truvada® ONE tablet ONCE daily and
   - Dolutegravir 50 mg ONE tablet ONCE daily.
   - Intent is to give the patient a chance to get drug coverage in place and take the prescription to the pharmacy to be filled
2. No assembled Peds PEP kits to date, currently assembled on an as needed basis
3. Duration of treatment is for 28 days in total

Question 17

How often to follow up on PEP treatment? (4)

Answer 17

1. All clients presenting to care following exposure should receive a baseline HIV test
2. Client should receive HIV test at:
   - 4-6 weeks post-exposure
   - 3 months post-exposure
   - 6 months post-exposure
3. Assess client for switch to PrEP following completion of PEP, should they have ongoing risk factors
4. If exposure was traumatic event, linkage to care for mental health and other supports