Safety and Pharmacokinetics of Once-Daily Multiple-Dose Administration of Islatravir in Adults Without HIV.

BACKGROUND: Islatravir (MK-8591) is a novel nucleoside analog in development for the treatment and prevention of HIV-1 infection. Islatravir has potent antiviral activity and a long intracellular half-life. SETTING: A 3-panel, randomized, double-blind, placebo-controlled, multiple-dose study in 36 adults without HIV evaluated the safety, tolerability, and pharmacokinetics of islatravir after daily administration. METHODS: Islatravir or placebo was administered orally once daily for 42 days (5 mg) or 28 days (0.25 mg; 0.75 mg). Blood samples were taken at prespecified time points for pharmacokinetic analysis of islatravir (plasma) and islatravir-triphosphate (ISL-TP; peripheral blood mononuclear cells [PBMCs]). Rectal and vaginal tissue samples were also collected in a subset of participants. Safety and tolerability were evaluated throughout. RESULTS: The pharmacokinetics of islatravir were approximately dose proportional, with concentrations approaching a steady state between days 14 and 21 in plasma and by day 28 for ISL-TP in PBMCs. Plasma exposure accumulation was 1.5-fold to 1.8-fold, and ISL-TP exposure accumulation was ∼10-fold. The apparent terminal half-life of ISL-TP was 177-209 hours. The ISL-TP pharmacokinetic trough threshold-the minimal concentration required for efficacy-of 0.05 pmol/106 cells was achieved after a single administration at all dose levels. Rectal and vaginal tissue also exhibited potentially therapeutic concentrations. Islatravir was generally well tolerated at all doses. CONCLUSIONS: ISL-TP levels in PBMCs were above the threshold projected for antiviral efficacy against wild-type HIV after a single 0.25-mg dose. Multiple once-daily dosing of islatravir in adults without HIV was generally well tolerated up to doses of 5 mg administered for up to 6 weeks.

A Phase 1 Randomized, Double-Blind, Placebo-Controlled Trial to Assess the Safety, Tolerability, and Pharmacokinetics of a Respiratory Syncytial Virus Neutralizing Monoclonal Antibody MK-1654 in Healthy Adults.

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infection and related morbidity and mortality in infants. Passive immunization with an RSV-neutralizing antibody can provide rapid protection to this vulnerable population. Proof-of-concept for this approach has been demonstrated by palivizumab; however, the use of this antibody is generally restricted to the highest-risk infants due to monthly dosing requirements and its cost. To address the large unmet medical need for most infants, we are evaluating MK-1654, a fully human RSV-neutralizing antibody with half-life extending mutations targeting site IV of the fusion protein. In this 2-part, placebo-controlled, double-blind, first-in-human study, 152 healthy adults were randomized 3:1 to receive a single dose of MK-1654 or placebo in 5 cohorts (100 or 300 mg as an intramuscular dose or 300, 1000, or 3000 mg as an intravenous dose). Safety, pharmacokinetics, antidrug antibodies, and RSV serum-neutralizing antibody titers were evaluated through 1 year. MK-1654 serum concentrations increased proportionally with dose and resulted in corresponding elevations in RSV serum-neutralizing antibody titers. The antibody displayed a half-life of 73 to 88 days and an estimated bioavailability of 69% at the 300-mg dose. The overall safety profile of MK-1654 was similar to placebo, and treatment-emergent antidrug antibodies were low (2.6%) with no associated adverse events. These data support the continued development of MK-1654 for the prevention of RSV disease in infants.

Investigation of Pharmacokinetic Interactions between Doravirine and Elbasvir-Grazoprevir and Ledipasvir-Sofosbuvir.

Doravirine is a non-nucleoside reverse transcriptase inhibitor for the treatment of human immunodeficiency virus type 1 (HIV-1) infection. Due to the high prevalence of HIV-1 and hepatitis C virus (HCV) coinfection and coadministration of HIV-1 and HCV treatment, potential drug-drug interactions (DDIs) between doravirine and two HCV treatments were investigated in two phase 1 drug interaction trials in healthy participants. Trial 1 investigated the effect of multiple-dose doravirine and elbasvir + grazoprevir coadministration (N = 12), and trial 2 investigated the effect of single-dose doravirine and ledipasvir-sofosbuvir coadministration (N = 14). Doravirine had no clinically relevant effect on the pharmacokinetics of elbasvir, grazoprevir, ledipasvir, sofosbuvir, or the sofosbuvir metabolite GS-331007. Coadministration of elbasvir + grazoprevir with doravirine moderately increased doravirine area under the concentration-time curve from 0 to 24 h (AUC0-24), maximal concentration (Cmax), and concentration 24 h postdose (C24), with geometric least-squares mean ratio (GMR) with 90% confidence intervals (CI) of 1.56 (1.45, 1.68), 1.41 (1.25, 1.58), and 1.61 (1.45, 1.79), respectively. Doravirine AUC0-∞, Cmax, and C24 values increased slightly following coadministration with ledipasvir-sofosbuvir (GMR [90% CI] of 1.15 [1.07, 1.24], 1.11 [0.97, 1.27], and 1.24 [1.13, 1.36], respectively). The modest increases in doravirine exposure are not clinically meaningful based on the therapeutic profile of doravirine. Effects are likely secondary to cytochrome P450 3A and P-glycoprotein inhibition by grazoprevir and ledipasvir, respectively. Coadministration of doravirine with elbasvir + grazoprevir or ledipasvir-sofosbuvir was generally well tolerated. Clinically relevant DDIs are not expected to occur between doravirine and elbasvir-grazoprevir or ledipasvir-sofosbuvir at the therapeutic doses.

Impact of a Diabetes Risk Score on Lifestyle Education and Patient Adherence (IDEA) in Prediabetes: A Multisite Randomized Controlled Trial.

BACKGROUND: To evaluate whether knowledge of a personalized Diabetes Risk Score (DRS) improved performance in a 12-week lifestyle change program for prediabetes. METHODS: Randomized subjects at four clinics provided samples for a DRS at baseline, 12, and 24 weeks. The intervention group received scores at each point, whereas the control group only received this information at 12 and 24 weeks. Outcomes included attendance and changes in weight, abdominal circumference, blood pressure, fasting glucose, hemoglobin A1c, cholesterol, and risk score. RESULTS: Baseline characteristics were similar in the groups (n = 192) and within risk-stratified subgroups. At 12 weeks, there were no differences in outcomes, with mean weight loss of 4.61 kg in the intervention group and 4.43 kg in the control group (p = 0.79). Both groups were given 12-week risk scores, with previously unseen baseline scores for the control group. The control group continued to lose additional weight (1.21 kg) by 24 weeks, whereas the intervention group regained previously lost weight (0.33 kg) (p = 0.04). CONCLUSIONS: The knowledge of a single baseline personalized DRS did not affect performance in a lifestyle modification program. However, the knowledge of an improvement in risk score, and the timing of this information, may impact further adherence.