Table 1_Prevalence and transmission of pretreatment drug resistance and acquired drug resistance among people living with HIV-1 in Chongqing, China, 2014–2024.docx

For NNRTIs, a high proportion of potential low-level resistance was observed in patients with PDR; by contrast, nevirapine (NVP) and efavirenz (EFV) showed a high proportion of high-level resistance in the ADR population. Notably, high prevalence of resistance to various antiretroviral therapy (ART) drugs was observed in the dominant HIV-1 CRF07_BC subtype. M184V (NRTI-associated mutation) and V179D (NNRTI-associated mutation) were the most frequently identified observed in PDR and ADR sequences; in contrast, the prevalent drug resistance mutation sites associated with PIs and INSTIs differed between PDR and ADR cases.

In CRF07_BC with PDR and ADR, the most prevalent mutations were V179D and M184V, respectively. Furthermore, distinct patterns of drug resistance mutations associated with different ART regimens were observed when comparing PDR and ADR populations. Among ART-naive PLWH, females and CRF08_BC were identified as significant risk factors for HIVDR.

In contrast, among ART-treated PLWH, risk factors such as HIV-1 subtypes and ART regimens were associated with HIV drug resistance.</p>Conclusion<p>Collectively, these results revealed the distinct epidemiological profiles of PDR and ADR in Chongqing area, underscoring the necessity of sustained, routine surveillance of PDR and ADR, and providing strong support to guide personalized regimen selection and reduce the risk of virological failure.</p>