What is the most cost-effective medication for post-exposure prophylaxis (PEP)?

Most Cost-Effective Medication for HIV Post-Exposure Prophylaxis (PEP)

The basic regimen of generic tenofovir disoproxil fumarate (TDF) plus lamivudine (3TC) is the most cost-effective medication regimen for HIV PEP, providing effective prophylaxis while minimizing cost. 1

Understanding PEP Regimen Options

PEP is recommended for individuals who have had exposure to potentially HIV-infected blood or body fluids when that exposure represents a substantial risk for HIV transmission and when care is sought within 72 hours of exposure 2.

Basic vs. Expanded Regimens

Two main approaches exist for PEP medication selection:

1. Basic Regimen (2-drug):

   • TDF + 3TC (or FTC) - recommended as the preferred backbone regimen 2
   • Lower cost than 3-drug regimens
   • Acceptable option when risk of drug resistance is low 2

2. Expanded Regimen (3-drug):

   • Basic regimen plus a third drug (protease inhibitor or integrase inhibitor)
   • Recommended by more recent guidelines for all exposures 2
   • Higher cost but potentially better efficacy

Cost-Effectiveness Analysis

When considering cost-effectiveness, several factors must be balanced:

• Generic TDF+3TC provides the best balance of efficacy and cost 1
• Single-tablet regimens improve adherence but come at significantly higher cost 1
• Modeling studies confirm that partially generic regimens like TDF+3TC are highly cost-effective 1

Third Drug Options (When 3-Drug Regimen Is Needed)

If a third drug is required (for high-risk exposures or possible resistance), the following options should be considered in order of cost-effectiveness:

1. Lopinavir/ritonavir (LPV/r) - suggested as preferred third drug 2
2. Atazanavir/ritonavir (ATV/r) - alternative option 2
3. Raltegravir (RAL), dolutegravir (DTG), or efavirenz (EFV) - effective but more expensive alternatives 2

Adherence and Completion Considerations

The cost-effectiveness of any PEP regimen depends on completion rates:

• TDF-based PEP regimens are better tolerated than those containing zidovudine 2
• Enhanced adherence counseling is suggested for all individuals initiating HIV PEP 2
• A full 28-day prescription should be provided following initial risk assessment 2

Administration Protocol

For maximum cost-effectiveness and efficacy:

1. Initiate PEP as soon as possible - ideally within 24 hours but no later than 72 hours after exposure 1
2. Prescribe a full 28-day course 2, 1
3. Schedule follow-up within 72 hours of starting PEP to monitor for drug toxicity 1
4. Conduct HIV testing at baseline, 6 weeks, 3 months, and 6 months post-exposure 1

Special Considerations

• Renal function: TDF may require dose adjustment in patients with renal impairment 1, 3
• Pregnancy: TDF-based regimens are generally considered safe during pregnancy 1
• Drug interactions: Consider potential interactions with other medications the patient may be taking 3, 4

Common Side Effects

Be aware of common side effects that may affect adherence:

• Gastrointestinal issues (nausea, diarrhea) 1, 5
• Fatigue 1, 5
• Headache 5
• Temporary decrease in estimated glomerular filtration rate 5

Conclusion

For maximum cost-effectiveness in HIV PEP, generic TDF+3TC represents the optimal balance of efficacy, tolerability, and cost. When a third drug is needed, LPV/r provides the most cost-effective option as recommended by current guidelines.