CME
Physicians: maximum of 1.00 AMA PRA Category 1 Credit
Released: June 09, 2025
Expiration: June 08, 2026
PrEP Regimens Used in Asia
PrEP Options for Patients With Renal Dysfunction
When prescribing PrEP, healthcare professionals (HCPs) need to consider whether a client’s clinical profile and medical history will affect the type of PrEP they can be prescribed.
In particular, a client's renal health should be considered, as tenofovir disoproxil fumarate (TDF) is secreted through the kidney and can potentially cause kidney damage. Although this renal dysfunction can be reversed with discontinuation of TDF, recovery is sometimes incomplete. As such, TDF is not recommended for patients below a certain level of kidney function.1,2
As you can see with this diagram, TDF-based PrEP is suitable for people with good kidney function, defined as creatinine clearance 60 mL/min or greater. However, a tenofovir alafenamide (TAF)-based PrEP regimen can be given to those with lower creatinine clearance, although not lower than 30 mL/min.1-3
Clinical trial data show that long-acting (LA) cabotegravir (CAB) is suitable for individuals with renal problems and is unlikely to cause renal dysfunction based on how it is excreted.
Ultimately, when I encounter clients with reduced kidney function, I tend to switch them from an oral TDF-based regimen to either a TAF-based one, LA CAB, or the dapivirine vaginal ring, if appropriate.1,2,4
Summary of Renal, Bone, and Weight Outcomes With Various PrEP Options
Other factors that can help determine the most suitable PrEP regimen are bone health and weight.
Oral TDF-based PrEP is associated with bone mineral density loss in some users. The good news is that it can help maintain or even mildly reduce weight when used daily, although these weight effects are not seen when it is used in an event-driven fashion.5-8
TAF-based PrEP is not associated with any negative bone or renal effects. In fact, switching to TAF-based PrEP from TDF-based PrEP can improve renal outcomes and bone mineral density. However, studies show that people who use TAF-based PrEP experienced an increase in weight at Week 96 of usage.9-11
Data from the HPTN 083 study demonstrated that LA CAB might be better at preserving bone mineral density compared to oral TDF-based PrEP.12-14
Participants in studies of LA CAB reported some weight gain in the first 40 weeks after initiating LA CAB, though overall changes in weight were comparable to TDF-based PrEP later on in the trials.12,13
PrEP for Patients With HBV Coinfection
Another aspect to consider before prescribing PrEP is whether clients have any coinfections, such as hepatitis B. Most guidelines recommend an initial assessment for HBV infection via hepatitis B surface antigen (HBsAg) and anti-hepatitis B surface antibody (HBs) testing, although this is not mandatory for PrEP initiation.15-17
If the assessment is performed and returns a negative result, hepatitis B vaccination should be recommended to all individuals without HBV immunity. Meanwhile, individuals who request PrEP but who require treatment for HBV should be prescribed an oral PrEP regimen that contains tenofovir, such as a TDF- or TAF-based regimen, owing to the efficacy of these drugs against both HBV and HIV.15-17
By contrast, LA CAB is not effective against hepatitis B infection. making it not ideal for those living with hepatitis B.15-17
Although some guidelines also allow people with HBV to take on-demand or event-driven PrEP, these regimens may not be ideal in this population because of the potential for HBV reactivation during periods between PrEP courses.15-17
PrEP for Patients With HCV Coinfection
Just as HBV infection is not a contraindication for PrEP, neither is hepatitis C virus (HCV) coinfection.
Similar to HBV, it is recommended that every individual receive screening for HCV infection, but it is not mandatory for PrEP initiation.15,18
Those who are diagnosed with hepatitis C should be linked to care to ensure the fastest track to treatment. Proper counseling should be given to those without hepatitis C to reduce the risk of HCV acquisition.15,19
Contraindications for PrEP
PrEP is suitable for most people but is contraindicated in a few specific populations.
First, people living with HIV should not take PrEP as it increases the likelihood of developing HIV drug resistance in the future.18,20
Second, people who are indicated for post-exposure prophylaxis (PEP), such as those who have been exposed to HIV in the past 72 hours, are contraindicated for PrEP. These people will benefit more from using PEP, however, they are eligible for PrEP after they finish their PEP regimens.18
Third, people with suspected acute HIV infection and potential HIV exposure in the last 14 days should not take PrEP as it can complicate diagnosis by reducing or delaying detection of viral antigens. This is why it is essential for HCPs to ensure that clients do not have symptoms of acute HIV infection at the time of PrEP initiation.18
Lastly, people with a contraindication, allergy, or hypersensitivity to PrEP products should not be given PrEP.18
Baseline Testing and Monitoring
The table on this slide details laboratory tests that should be performed or considered before initiating and while taking PrEP. As you can see, PrEP eligibility has been extensively simplified. The only mandatory baseline testing and monitoring is for HIV RNA.18
For people using oral PrEP and the dapivirine vaginal ring, it is imperative that they undergo HIV RNA testing at initiation and every 3 months afterwards, with an optional test 1 month post initiation.18
For people using LA CAB, HIV RNA monitoring is going to be more frequent. Individuals should be tested at the day of initiation, then 1 month later, and then every 2 months.18
HCPs may also consider monitoring creatinine and estimated glomerular filtration rate in patients on oral PrEP, which can identify whether these patients are experiencing renal dysfunction. These kidney function tests should be prioritized in people younger than 50 years old and those with underlying kidney-related comorbidities. For those younger than 50 years old without any kidney-related comorbidities, this monitoring is optional.18
HCPs might consider baseline assessment of alanine aminotransferase in people on LA CAB, especially among individuals who may have acute hepatitis.18
And lastly, screening for other sexually transmitted infections is optional but highly encouraged. Individuals should be screened for HBV, HCV, and other sexually transmitted infections such as syphilis, chlamydia, and gonorrhea, within 3 months of starting PrEP and every 3 to 6 months thereafter according to their individual risk factors.18
Addressing Common Adverse Events
Although PrEP is generally well-tolerated, HCPs may need to address adverse events (AEs), particularly for people who have just started using PrEP. Here, I will review some common AEs associated with different PrEP regimens, and potential methods of mitigating them.
A common AE with TDF, TAF, and LA CAB is GI upset, such as nausea, dizziness, flatulence, or diarrhea. If needed, GI upset can usually be managed with over-the-counter medications. However, most cases do not require treatment and will resolve within 5 to 10 days after PrEP initiation.2-4,18
For TDF-based oral PrEP, the potential for renal dysfunction and loss of bone mineral density must be discussed before PrEP initiation.2,18
However, although it is important to make patients aware of this potential, HCPs should also note that these side effects are very rare. Clinical trials reported that less than 10% of participants experienced these types of AEs, and they are generally reversible after discontinuation of the drug. Patients should be counseled both on the potential for and rarity of these AEs.2,18,21
With TAF-based PrEP, the conversation about renal dysfunction and bone mineral density loss is not necessary, but patients should still be informed about the possibility of GI upset and weight gain.3,18
For LA CAB, the most important AE to discuss with patients is the potential for injection-site reactions. According to data from HPTN 083, approximately 80% of participants reported injection-site reactions after the first injection. However, these reactions should decrease over time and are manageable using over-the-counter pain management.12
Lastly, the dapivirine vaginal ring is associated with an increased risk of urinary tract infections and vaginal itching. For these issues, I usually tell patients to come for an in-person assessment to rule out other causes that can manifest similar side effects.18
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