Switching antiretroviral regimes for the treatment of HIV: safety implications

Pharmacokinetic testing of a first-generation cabotegravir prodrug in rhesus macaques

: Long-acting antiretrovirals can improve therapy and prevention for HIV-1 infection. Current long-acting cabotegravir (CAB LAP) can be administered every other month. Previously, we demonstrated that a myristoylated CAB prodrug encased in poloxamer 407 provided extended plasma drug concentrations. We now demonstrate that this first-generation nanoformulated prodrug can sustain plasma CAB concentrations above the protein-adjusted 90% inhibitory concentration for 4 months in rhesus macaques. A 2.5-fold extension in CAB half-life and a 1.6-fold increase in area under the concentration-time curve were observed compared with CAB LAP.

Pharmacokinetics of a Long-Acting Nanoformulated Dolutegravir Prodrug in Rhesus Macaques

A nanoformulated myristoylated dolutegravir prodrug (NMDTG) was prepared using good laboratory practice protocols. Intramuscular injection of NMDTG (118 ± 8 mg/ml, 25.5 mg of DTG equivalents/kg of body weight) to three rhesus macaques led to plasma DTG levels of 86 ± 12 and 28 ± 1 ng/ml on days 35 and 91, respectively. The NMDTG platform showed no significant adverse events. Further modification may further extend the drug's apparent half-life for human use.

Reasons for switching ART: Comparison of data collected in 2012-2013 and 2014-2015 in Florence, Italy

Persons living with HIV should remain on antiretroviral therapy (ART) indefinitely; however, a switch in the drug regimen is often necessary. In order to investigate if reasons for switching ART changed over time, we retrospectively analyzed reasons for switching and characteristics of switches among patients at Santa Maria Annunziata Hospital (OSMA), Florence area, Tuscany, Italy, over two periods (November 2012-October 2013 and November 2014-October 2015). The reasons for switching were classified as: simplification; virologic failure; occurrence of co-morbidities; and drug tolerability/toxicity issues. In period 1 (2012-2013), 18% patients changed their regimen vs. 13.5% in period 2 (2014-2015) (p = 0.019). Among reasons for switching, switches for simplification significantly increased from 41% in period 1 to 53% in period 2 (p = 0.004), with an increasing use of single tablet regimens (p = 0.002); no other statistically significant differences were found in other reasons for switching in periods 1 and 2. Characteristics of patients and of switches were analyzed and described. According to our data, the main reason for switching is now simplification, reflecting the recent changes in recommendations aimed to enhance adherence and quality of life, and to minimize, at the same time, drug toxicity and side effects.