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Updated: Aug 21, 2026
An Affordable HIV-1 Drug Resistance Monitoring Method for Resource Limited Settings
Published on: March 30, 2014
Performance of plasma separation cards for HIV drug-resistance genotyping in a resource-limited setting: comparison
Thang Hong Pham1, Hanh Thi Hong Ngo1, Tram Thi Phuong Pham1
1National Institute of Hygiene and Epidemiology (NIHE), Hanoi 100000, Vietnam.
Insights
The Cobas Plasma Separation Card (PSC) shows high accuracy for HIV drug resistance genotyping compared to plasma. This method can expand access to HIV genotyping in resource-limited settings.
Area of Science:
- Virology
- Public Health
- Clinical Diagnostics
Background:
- HIV drug resistance (HIVDR) poses a significant threat to the efficacy of antiretroviral therapy (ART) in low- and middle-income countries.
- The Cobas Plasma Separation Card (PSC) offers a promising solution for decentralized HIVDR genotyping, potentially improving access in remote areas.
Purpose of the Study:
- To evaluate the performance of the Cobas Plasma Separation Card (PSC) for HIV drug resistance genotyping against traditional plasma methods.
Main Methods:
- Paired plasma and PSC specimens were collected from 250 individuals with HIV on ART and viral load ≥1000 copies/mL.
- HIVDR genotyping was performed using the CDC Atlanta in-house protocol, with resistance interpretation via the Stanford HIVdb algorithm.
- Paired sequences were analyzed for subtype, nucleotide similarity, mutation profiles, and drug resistance classification.
Main Results:
- Of 20 valid paired specimens, HIV-1 Pol gene amplification was successful in 95% of PSC samples.
- Nucleotide similarity between PSC and plasma sequences was high at 98.5%.
- 94.6% of major drug-resistance mutations identified in plasma were concordantly found in PSC specimens, with minimal impact on clinical interpretation.
Conclusions:
- The Cobas Plasma Separation Card (PSC) demonstrates strong concordance with plasma for HIV drug resistance genotyping.
- PSC is a viable alternative specimen type for HIVDR genotyping in clinical practice and surveillance, particularly in resource-limited settings.
Background:
HIV drug resistance (HIVDR) threatens the effectiveness of antiretroviral therapy (ART) programmes in low- and middle-income countries. The Cobas Plasma Separation Card (PSC) is a recently developed specimen collection tool with potential to expand access to HIVDR genotyping in remote settings. This study evaluates PSC performance for HIVDR genotyping compared with plasma.
Methods:
Paired plasma and PSC specimens were selected from 250 people living with HIV (PLHIV) on ART ≥6 months with viral load (VL) ≥1000 copies/mL. HIVDR genotyping followed CDC Atlanta in-house protocol; resistance interpretation used the Stanford HIVdb algorithm. Paired sequences were compared for subtype, nucleotide similarity, mutation profile and drug-resistance classification.
Results:
Twenty paired specimens met inclusion criteria. Amplification of the HIV-1 Pol gene succeeded in 19/20 (95%) PSC samples. Of 19 paired sequences, nucleotide similarity was 98.5% (IQR 98.0%-99.3%). Eleven plasma samples showed 37 major drug-resistance mutations (MDM); 35 (94.6%) concordant MDM were identified in PSC. Discordances in four pairs were limited to mixed versus single bases and did not alter drug-resistance classification. Only one pair showed a clinically significant discordance (K103N detected in plasma but not initially in PSC).
Conclusions:
PSC demonstrated good concordance with plasma for HIVDR genotyping and has potential as an alternative specimen type for clinical practice and surveillance in resource-limited settings.
