Research Digest is a periodic installment that recognizes the world-class clinical research performed right here at UNMC ID. Today, we review two recent articles highlighting STI post-exposure prophylaxis and HIV treatment in patients with substance use disorders. As always, check out the linked full articles for more details.
Utilization of Doxycycline Post-Exposure Prophylaxis at a Midwestern United States HIV/PrEP Clinic. Open Forum Infectious Diseases, January 30, 2025 (Editor’s Choice)
This study assessed doxycycline post-exposure prophylaxis (doxy PEP) prescribing and adherence to CDC guidelines at the University of Nebraska Medical Center’s Specialty Care Center (UNMC SCC). Doxy PEP reduces sexually transmitted infections (STIs), including Neisseria gonorrhoeae, Chlamydia trachomatis, and Treponema pallidum.
Researchers retrospectively analyzed prescriptions from March 2023 to February 2024 for adherence to recommended follow-ups and STI screenings. Among 90 patients (97.8% male, average age 38.6), 70% received doxy PEP per protocol, while 30% had non-adherent prescriptions, primarily due to missed STI screenings (89%), particularly for syphilis.
The median prescription was five doses, with a median 32% coverage of days. While 13% of patients were diagnosed with an STI during doxy PEP use, syphilis incidence was significantly lower compared to the clinic’s background rate (1.8% vs. 6.9%, p = 0.01). Missed screenings, possibly due to cost barriers, pose a challenge to doxy PEP’s effectiveness and may contribute to antimicrobial resistance risks.
The study highlights the need for affordable STI screening, routine monitoring, and individualized prescribing to optimize doxy PEP’s impact on STI prevention. Read the full article here.
The BASE study evaluated the long-term efficacy and adherence of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in people with HIV and substance use disorders (PWH/SUD). At 96 weeks, viral suppression (HIV RNA <50 copies/mL) declined to 44% (intent-to-treat), with adherence decreasing by 18% compared to the first 48 weeks. Despite lower adherence, no treatment-emergent resistance was observed, supporting B/F/TAF’s high barrier to resistance. Retention in care remained stable at 83.7%, but substance use, particularly methamphetamines, persisted in 83% of participants.
Higher adherence (≥4 doses/week) significantly increased the likelihood of viral suppression (84% vs. 16%, p <0.01). Participants who lost suppression at week 96 had a 55% decline in adherence. Adverse events were common (53.5%), though none were attributed to B/F/TAF. Syphilis was the most frequently diagnosed infection (11.6%), and neuropsychiatric events occurred in 7%. Despite adherence challenges, B/F/TAF remained effective and well tolerated in this high-risk population.
The findings underscore the need for adherence support, substance use treatment, and social interventions to optimize HIV outcomes in PWH/SUD. Read the full article here.
*We are trying a new approach using AI to help summarize articles. These publications were summarized by ChatGPT (https://chatgpt.com/) and approved by the authors. There is always room for improvement. Let us know if we got it right, or if we got it wrong!*