Brief Report: Long-Acting Injectable PrEP Can Substantially Reduce HIV Incidence in Los Angeles County: A Simulation...

Area of Science:

• Public Health
• Epidemiology
• HIV Prevention Research

Background:

• Oral pre-exposure prophylaxis (PrEP) has reduced HIV incidence but faces adherence challenges due to daily dosing.
• Young Black men who have sex with men (YBMSM) are disproportionately affected by HIV.
• Long-acting injectable (LAI) PrEP presents a potential solution to improve adherence.

Purpose of the Study:

• To simulate the impact of introducing LAI PrEP among YBMSM in Los Angeles County.
• To evaluate how varying LAI PrEP uptake and retention rates affect HIV transmission.
• To compare the effectiveness of LAI PrEP against oral PrEP in reducing HIV incidence and prevalence.

Main Methods:

• Utilized an agent-based network model (ABNM) calibrated with empirical data.
• Simulated HIV transmission dynamics over 10 years, incorporating dynamic sexual networks and HIV progression.
• Modeled scenarios with different proportions of PrEP users switching to LAI and varying adherence levels to LAI retention.

Main Results:

• LAI PrEP substantially reduced HIV incidence and prevalence compared to oral PrEP alone.
• Retention rates of 60% or higher for LAI PrEP yielded reductions comparable to or exceeding oral PrEP.
• A 45% decrease in HIV incidence was observed when all PrEP users switched to LAI with 85% retention.

Conclusions:

• LAI PrEP shows significant potential for advancing HIV prevention among YBMSM by overcoming oral PrEP adherence issues.
• Integrating LAI PrEP into public health strategies can lead to substantial reductions in HIV incidence.
• LAI PrEP can contribute to ending the HIV epidemic in high-priority populations like YBMSM.