HIV‐1 Subtype Shift in the Philippines is Associated With High Transmitted Drug Resistance, High Viral Loads, and Fast Immunologic Decline

• Published in: International journal of infectious diseases 2022-09, Vol.122, p.936-943
• Main Authors: Salvaña, Edsel Maurice T., Dungca, Niña Theresa, Arevalo, Geraldine, Li, Kingbherly, Francisco, Christian, Penalosa, Christine, dela Tonga, Angelo, Leyritana, Katerina, Solante, Rontgene, Tactacan-Abrenica, Rosario Jessica, Lim, Jodor, Alejandria, Marissa, Palaypayon, Noel, Schwem, Brian
• Format: Article
• Language: English
• Subjects: CRF01_AE; Drug resistance; Epidemiology; HIV; Philippines
• ISSN: 1201-9712; 1878-3511
• DOI: 10.1016/j.ijid.2022.06.048

•Transmitted drug resistance in the Philippines is high.•CRF01_AE is associated with higher viral load and lower CD4.•Drug-resistance testing is recommended in the Philippines when initiating antiretroviral therapy. The Philippines has one of the fastest growing HIV epidemics in the world. A subtype shift from B to CRF01_AE may have contributed to the increase in cases. We undertook a genotyping and transmitted drug resistance (TDR) study to determine if the dominant subtype has any advantages in resistance and transmission. Filipinos who were treatment-naive who were living with HIV were recruited from two large government treatment hubs from March 2016 to August 2018. HIV-1 viral load, CD4 count, genotyping, and TDR testing were performed. Demographic and clinical data were collected and compared across subtypes. A total of 298 Filipinos living with HIV were recruited. Median CD4 count was 143 cells/µl and HIV viral load was 2,345,431 copies/ml. Sanger-based sequencing showed 230/298 (77.2%) had subtype CRF01_AE, 41 (13.8%) subtype B, and the rest had other subtypes or recombinants. Overall TDR was 11.7%. TDR was associated with lower viral loads and no previous HIV testing. CRF01_AE had a higher likelihood of a viral load >100,000 copies/ml and having a baseline CD4 count