Raltegravir plus abacavir/lamivudine in virologically suppressed HIV-1-infected patients: 48-week results of the KIRAL study

Effectiveness of integrase strand transfer inhibitors among treatment-experienced patients in a clinical setting

OBJECTIVE

Characterize virologic and immunologic outcomes of INSTI-based antiretroviral therapy (ART) in experienced patients with and without virologic failure.

DESIGN

Prospective clinical cohort.

METHODS

ART-experienced, INSTI-naive participants in the University of North Carolina Center for AIDS Research HIV Clinical Cohort (UCHCC) initiating an INSTI-containing regimen 2007-2016 were followed from INSTI initiation (baseline) to the earliest of: outcome of interest, loss to follow-up (LTFU, 1 year without clinical visit), or death. Outcomes of interest were virologic failure (first of two consecutive viral loads at least 200 copies/ml more than 2 weeks apart, or one viral load ≥200 before LTFU) and immune recovery (first CD4 ≥500 cells/μl). Patients with baseline viral load at least 50 copies/ml were given 24 weeks before meeting virologic failure criteria. Kaplan-Meier curves and Cox proportional hazards models compared INSTI regimens and patient characteristics.

RESULTS

Of 773 patients, 32% were women, 59% African-American, and 42% had a viral load at least 50 copies/ml at INSTI initiation. After 2 years, 5% of patients with baseline viral load less than 50 copies/ml experienced virologic failure, compared with 35% of patients with baseline viral load at least 50 copies/ml (P < 0.01). Among patients with baseline viral load less than 50 copies/ml, dolutegravir/NRTIs was associated with longer time to virologic failure [adjusted hazard ratio (aHR) 0.11, 95% confidence interval (CI) 0.01-0.80], whereas among patients with baseline viral load at least 50 copies/ml, raltegravir/NRTIs was associated with longer time to virologic failure (aHR 0.35, 95% CI 0.18-0.68), both compared with elvitegravir/NRTIs. After 5 years suppressed, irrespective of baseline viral load, 61% of patients experienced immune recovery.

CONCLUSION

In this cohort, INSTI-containing regimens led to low virologic failure rates in patients switching ART while suppressed. Viremic patients initiating INSTIs were at high risk of virologic failure during follow-up.

Efficacy and safety of abacavir/lamivudine with raltegravir in treatment-experienced and treatment-naïve patients with HIV-1 infection: an observational, retrospective, multi-centre study

Raltegravir (RAL) is an HIV-1 integrase strand transfer inhibitor that is well established as a component of highly active antiretroviral therapy regimens for the treatment of adults living with human immunodeficiency virus (HIV), due to its high virological efficacy and good tolerability profile. To date, limited data are available on the use of RAL with abacavir/lamivudine (ABC/3TC). We investigated retrospectively 62 HIV-1 infected patients managed by three Italian Infectious Diseases Outpatient Departments, including 57 treatment-experienced patients and 5 treatment-naïve patients, treated with ABC/3TC plus RAL. In all five naïve patients (100%), virological suppression was achieved and maintained , while 55 experienced patients (96.5%) maintained viral suppression at the most recent review. In the treatment-experienced patients, we observed a significant decrease in triglyceride levels (p < 0.01), while liver transaminases, renal function and cholesterol levels remained substantially stable. In the 34 treatment-experienced patients who switched from a protease inhibitor (PI)-based regimen, we observed a significant improvement of total cholesterol (p=0.03) and triglyceride (p < 0.01) levels. No significant alterations were found on renal and liver function and serum lipid profile of treatment-naïve patients. Despite the small number of participants, results support the efficacy and safety of ABC/3TC plus RAL, either in treatment-naïve or treatment-experienced patients.

Alternative switching strategies based on regimens with a low genetic barrier: do clinicians have a choice nowadays?

Clinicians sometimes use switching strategies based on regimens such as RAL + ABC/3TC or RPV + ABC/3TC in order to resolve tolerability or safety issues associated with conventional recommended first-line strategies. Despite the low genetic barrier of these regimens, high safety and efficacy rates have been reported in retrospective studies.