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Symptoms, Side Effects and Adherence in the iPrEx Open-Label Extension
David V Glidden1, K Rivet Amico2, Albert Y Liu3
1University of California, San Francisco.
Pre-exposure prophylaxis (PrEP) symptoms are temporary and affect a minority of users. Gastrointestinal symptoms may slightly reduce adherence, but good adherence remains achievable.
Area of Science:
- Infectious Diseases
- Pharmacology
- Public Health
Background:
- Blinded trials noted transient
- start-up syndrome
- with tenofovir-based pre-exposure prophylaxis (PrEP).
- This study investigates PrEP-associated symptoms and adherence in an open-label setting.
Purpose of the Study:
- To evaluate the prevalence, duration, and impact of PrEP-associated symptoms on adherence.
- To assess symptom-related adherence in an open-label PrEP cohort.
Main Methods:
- 18-month open-label, multi-site study of daily oral tenofovir/emtricitabine.
- Assessed symptom prevalence and duration.
- Measured adherence via drug levels in dried blood spots for the first 3 months.
Main Results:
- Symptom reports peaked at month 1 (39%) versus baseline (22%), largely resolving by 3 months.
- Gastrointestinal (GI) symptoms in the first 4 weeks were inversely associated with adherence (OR=0.47).
- GI symptoms accounted for 7% of suboptimal adherence; non-GI symptoms showed no association.
Conclusions:
- PrEP-associated symptoms affect a minority, are transient, and mostly resolve within 3 months.
- GI symptoms are linked to a modest decrease in adherence.
- Good adherence is possible despite symptom reporting.
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