Prevalence of doravirine cross-resistance in HIV-infected adults who failed first-line ART in China, 2014-18.

Objectives: To evaluate the prevalence and characteristics of doravirine resistance and cross-resistance in patients who failed first-line ART in China.

Methods: From 2014 to 2108, 4132 patients from five provinces were tested for drug resistance by genotypic resistance testing. Drug resistance mutations were assessed using the Stanford HIVdb algorithm Version 9.0. Sequences classified as having low-level, intermediate and high-level resistance were defined as having drug resistance.

Results: Overall, the prevalence of doravirine and other NNRTIs cross-resistance was 69.5%, with intermediate and high-level resistance accounting for 56.4%. Doravirine resistance highly correlated with efavirenz (r = 0.720) and nevirapine (r = 0.721) resistance and moderately correlated with etravirine (r = 0.637) and rilpivirine (r = 0.692) resistance. The most frequent doravirine-associated resistance mutations were V106M (8.7%), K101E (6.8%) and P225H (5.1%). High-level resistance was mainly due to Y188L (3.2%) and M230L (2.7%). There were significant differences between genotypes and provinces. Compared with CRF01_AE, CRF07_BC (OR = 0.595, 95% CI = 0.546-0.648) and CRF08_BC (OR = 0.467, 95% CI = 0.407-0.536) were associated with lower risks of doravirine resistance. Conversely, genotype A (OR = 3.003, 95% CI = 1.806-4.991) and genotype B (OR = 1.250, 95% CI = 1.021-1.531) were associated with higher risks of doravirine resistance. The risk of doravirine resistance was significantly lower in Xinjiang compared with other provinces.

Conclusions: In China, the prevalence of doravirine cross-resistance among patients who have failed first-line ART is high. Therefore, doravirine should not be used blindly without genotypic resistance testing and is not recommended for people who have failed first-line NNRTI-based ART.