Antiretroviral treatment in HIV-1 infected pediatric patients: focus on efavirenz

Survey of Pretreatment HIV Drug Resistance and Genetic Transmission Network Analysis Among HIV Patients in a High Drug-Use Area of Southwest China

Background: Pretreatment drug resistance (PDR) poses an increasing threat to the success of antiretroviral treatment (ART) programs in China. We aimed to conduct a survey of PDR among HIV patients in an area in Southwest China with extensive drug trafficking.

Methods: Consecutive cross-sectional surveys were conducted in Liangshan Prefecture of Sichuan Province from 2009 to 2018 based on the WHO-recommended method. PDR was identified by testing pol region sequences with the Stanford HIVdb algorithm (version 7.0). PDR prevalence and related factors were assessed by multivariable logistic regression. The transmission of HIV drug resistance was analyzed using a genetic transmission network.

Results: HIV-1 pol genes from 1889 patients were successfully amplified. The distribution of HIV-1 genotypes was as follows: CRF07_BC (94.0%), CRF08_BC (2.3%), CRF01_AE (2.0%) and others (1.4%). Of the participants, 6.9% (95% CI: 4.1-8.1%) had pretreatment resistance to 12 antiretroviral drugs recommended by the WHO, and nucleoside reverse transcriptase inhibitor (NRTI), non-nucleoside reverse transcriptase inhibitor (NNRTI) and protease inhibitors (PI) resistance were identified among 1.4% (95% CI: 0.7-3.4%), 5.8% (95% CI: 1.2-8.7%) and 0.4% (95% CI: 0.1-3.0%) of the patients, respectively. In the multivariate logistic model, the prevalence of PDR was 1.52-fold higher among intravenous drug users (IDUs) than among patients infected by heterosexual transmission (95% CI: 1.07-2.38; P=0.049), and the prevalence of PDR among patients diagnosed from 2017-2018 was 2.03-fold higher than that among patients diagnosed from 2009-2016 (95% CI: 1.18-5.76; P=0.018). A total of 26 clusters containing PDR and a rapidly growing drug resistance-related cluster containing the E138Q and V179D mutations were identified by genetic transmission network analysis.

Conclusion: The results show a moderate overall level of PDR prevalence and rapidly growing drug resistance over time. Preventive intervention should be focused on controlling the HIV epidemic among drug users, and surveillance is urgently needed to monitor the trend of PDR.

Virologic response to efavirenz-based first-line antiretroviral therapy in children with previous exposure to antiretrovirals to prevent mother-to-child transmission

Efavirenz-based first-line regimens have been widely used for children ≥3 years of age starting antiretroviral therapy, despite possible resistance with prior exposure to non-nucleoside reverse transcriptase inhibitors for prevention of mother-to-child transmission (PMTCT). We used logistic regression to examine the association between PMTCT exposure and viral failure (VF) defined as two consecutive viral loads (VL)>1000 copies/ml between 6–18 months on ART. Children with previous nevirapine exposure for PMTCT were not at higher risk of VF compared to unexposed children (adjusted Odds Ratio (aOR): 0.79; 95% CI:0.56, 1.11).

Efavirenz-based simplification after successful early lopinavir-boosted-ritonavir-based therapy in HIV-infected children in Burkina Faso and Côte d'Ivoire: the MONOD ANRS 12206 non-inferiority randomised trial

BACKGROUND

The 2016 World Health Organization guidelines recommend all children <3 years start antiretroviral therapy (ART) on protease inhibitor-based regimens. But lopinavir/ritonavir (LPV/r) syrup has many challenges in low-income countries, including limited availability, requires refrigeration, interactions with anti-tuberculous drugs, twice-daily dosing, poor palatability in young children, and higher cost than non-nucleoside reverse transcriptase inhibitor (NNRTI) drugs. Successfully initiating LPV/r-based ART in HIV-infected children aged <2 years raises operational challenges that could be simplified by switching to a protease inhibitor-sparing therapy based on efavirenz (EFV), although, to date, EFV is not recommended in children <3 years.

METHODS

The MONOD ANRS 12026 study is a phase 3 non-inferiority open-label randomised clinical trial conducted in Abidjan, Côte d'Ivoire, and Ouagadougou, Burkina Faso (ClinicalTrial.gov registry: NCT01127204). HIV-1-infected children who were tuberculosis-free and treated before the age of 2 years with 12-15 months of suppressive twice-daily LPV/r-based ART (HIV-1 RNA viral load (VL) <500 copies/mL, confirmed) were randomised to two arms: once-daily combination of abacavir (ABC) + lamivudine (3TC) + EFV (referred to as EFV) versus continuation of the twice-daily combination zidovudine (ZDV) or ABC + 3TC + LPV/r (referred to as LPV). The primary endpoint was the difference in the proportion of children with virological suppression by 12 months post-randomisation between arms (14% non-inferiority bound, Chi-squared test).

RESULTS

Between May 2011 and January 2013, 156 children (median age 13.7 months) were initiated on ART. After 12-15 months on ART, 106 (68%) were randomised to one of the two treatment arms (54 LPV, 52 EFV); 97 (91%) were aged <3 years. At 12 months post-randomisation, 46 children (85.2%) from LPV versus 43 (82.7%) from EFV showed virological suppression (defined as a VL <500 copies/mL; difference, 2.5%; 95% confidence interval (CI), -11.5 to 16.5), whereas seven (13%) in LPV and seven (13.5%) in EFV were classed as having virological failure (secondary outcome, defined as a VL ≥1000 copies/mL; difference, 0.5%; 95% CI, -13.4 to 12.4). No significant differences in adverse events were observed, with two adverse events in LPV (3.7%) versus four (7.7%) in EFV (p = 0.43). On genotyping, 13 out of 14 children with virological failure (six out of seven EFV, seven out of seven LPV) had a drug-resistance mutation: nine (five out of six EFV, four out of seven LPV) had one or more major NNRTI-resistance mutations whereas none had an LPV/r-resistance mutation.

CONCLUSIONS

At the VL threshold of 500 copies/mL, we could not conclusively demonstrate the non-inferiority of EFV on viral suppression compared to LPV because of low statistical power. However, non-inferiority was confirmed for a VL threshold of <1000 copies/mL. Resistance analyses highlighted a high frequency of NNRTI-resistance mutations. A switch to an EFV-based regimen as a simplification strategy around the age of 3 years needs to be closely monitored.

TRIAL REGISTRATION

ClinicalTrial.gov registry n° NCT01127204 , 19 May 2010.

Antiretroviral treatment in HIV-infected children who require a rifamycin-containing regimen for tuberculosis

INTRODUCTION

In high prevalence settings, tuberculosis and HIV dual infection and co-treatment is frequent. Rifamycins, especially rifampicin, in combination with isoniazid, ethambutol and pyrazinamide are key components of short-course antituberculosis therapy. Areas covered: We reviewed available data, for which articles were identified by a Pubmed search, on rifamycin-antiretroviral interactions in HIV-infected children. Rifamycins have potent inducing effects on phase I and II drug metabolising enzymes and transporters. Antiretroviral medications are often metabolised by the enzymes induced by rifamycins or may suppress specific enzyme activity leading to drug-drug interactions with rifamycins. These may cause significant alterations in their phamacokinetic and pharmacodynamic properties, and sometimes that of the rifamycin. Recommended strategies to adapt to these interactions include avoidance and dose adjustment. Expert opinion: Despite the importance and frequency of tuberculosis as an opportunistic disease in HIV-infected children, current data on the management of co-treated children is based on few studies. We need new strategies to rapidly assess the use of rifamycins, new anti-tuberculosis drugs and antiretroviral drugs together as information on safety and dosing of individual drugs becomes available.

An analysis of drug resistance among people living with HIV/AIDS in Shanghai, China

BACKGROUND

Understanding the mechanisms of drug resistance can facilitate better management of antiretroviral therapy, helping to prevent transmission and decrease the morbidity and mortality of people living with HIV/AIDS. However, there is little data about transmitted drug resistance and acquired drug resistance for HIV/AIDS patients in Shanghai.

METHODS

A retrospective cohort study of HIV-infected patients who visited the Department of Infectious Disease from June 2008 to June 2015 was conducted in Shanghai, China. Logistic regression analysis was performed to analyze risk factors for drug resistance among HIV-infected people with virological failure. The related collected factors included patient age, gender, marital status, infection route, baseline CD4 count, antiretroviral therapy regimens, time between HIV diagnosis and initiating antiretroviral therapy. Factors with p<0.1 in the univariate logistic regression test were analyzed by multivariate logistic regression test.

RESULTS

There were 575 subjects selected for this study and 369 participated in this research. For the antiretroviral therapy drugs, the rates of transmitted drug resistance and acquired drug resistance were significantly different. The non-nucleoside reverse transcriptase inhibitor (NNRTI) had the highest drug resistance rate (transmitted drug resistance, 10.9%; acquired drug resistance, 53.3%) and protease inhibitors (PIs) had the lowest drug resistance rate (transmitted drug resistance, 1.7%; acquired drug resistance, 2.7%). Logistic regression analysis found no factors that were related to drug resistance except marital status (married status for tenofovir: odds ratio = 6.345, 95% confidence interval = 1.553-25.921, P = 0.010) and the time span between HIV diagnosis and initiating antiretroviral therapy (≤6M for stavudine: odds ratio = 0.271, 95% confidence interval = 0.086-0.850, P = 0.025; ≤6M for didanosine: odds ratio = 0.284, 95% confidence interval = 0.096-0.842, P = 0.023; ≤6M for tenofovir: odds ratio = 0.079, 95% confidence interval = 0.018-0.350,P<0.001).

CONCLUSION

NNRTI had a higher DR rate compared with nucleoside reverse transcriptase inhibitor (NRTI) and PIs, consequently, LPV/r was a reasonable choice for patients with NNRTI drugs resistance in China. Only married status and a time span≤6 month between the HIV confirmed date and the time initiating antiretroviral therapy were risk factors for TDF drug resistance. Both baseline HIV-RNA load and resistance test is crucial for TDR diagnosis, and frequent monitoring of HIV-RNA load is crucial for ADR identification and intervention. Treatment adherence still plays a positive role on the outcome of ART.