Bioequivalence of a Pediatric Fixed-Dose Combination Tablet Darunavir/Cobicistat/Emtricitabine/Tenofovir Alafenamide Compared With Coadministration of the Separate Agents in Healthy Adults: An Open-Label, Randomized, Replicate Crossover Study

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg is a fixed-dose combination (FDC) for the treatment of HIV-1 infection in adults and adolescents weighing 40 kg or greater. This Phase 1, randomized, open-label, 2-treatment, 2-sequence, 4-period replicate crossover study (NCT04661397) evaluated the pivotal bioequivalence of a pediatric D/C/F/TAF 675/150/200/10-mg FDC compared with coadministration of the separate commercially available formulations in healthy adults under fed conditions. During each period, participants received either a single oral dose of D/C/F/TAF 675/150/200/10-mg FDC (test) or a single oral dose of darunavir 600 and 75 mg, cobicistat 150 mg, and emtricitabine/tenofovir alafenamide 200/10-mg FDC (reference). Thirty-seven participants were randomly assigned to one of 2 treatment sequence groups: test-reference-reference-test or reference-test-test-reference, with 7 days or more washout between periods. The 90% confidence intervals of the geometric mean ratios for maximum plasma concentration, area under the concentration-time curve from time zero to last measurable concentration, and area under the concentration-time curve extrapolated to infinity for darunavir, cobicistat, emtricitabine, and tenofovir alafenamide fell within conventional bioequivalence limits (80%-125%). No Grade 3/4 adverse events, serious adverse events, or deaths occurred. In conclusion, administration of D/C/F/TAF 675/150/200/10-mg FDC was bioequivalent to coadministration of the separate commercially available formulations.

In vitro evaluation of poloxamer in situ forming gels for bedaquiline fumarate salt and pharmacokinetics following intramuscular injection in rats

The objective of this study was to evaluate in vitro and in vivo drug release from in situ forming gels prepared with poloxamer 338 (P338) and/or 407 (P407) in N-methyl-2-pyrrolidone (NMP)/water mixtures for the model compound bedaquiline fumarate salt. The impact of total poloxamer concentration (20%–25% (w/w)), P338/P407 ratio (100/0%–0/100% (w/w)) and NMP/water ratio (0/100%–25/75% (v/v)) on gel point temperature (GPT) was investigated via a design of experiments (DoE), showing that GPT decreased mainly with increasing poloxamer concentration and decreasing P338/P407 ratio, while the relation with NMP/water ratio was more complex resulting in a flexion. Based on the DoE, four formulations with 10 mg/g bedaquiline fumarate salt, a fixed NMP/water ratio of 25/75% (v/v) and varying total poloxamer concentration and P338/P407 ratio were selected for evaluation of gel erosion in vitro. The fastest eroding formulation had the lowest total poloxamer concentration (20% (w/w)) and the lowest P338/P407 ratio (20.4/79.6% (w/w)), while the formulation with the highest total poloxamer concentration (23.5% (w/w)) and highest P338/P407 ratio (100/0% (w/w)) showed the lowest gel erosion rate. These fast and slow eroding formulations showed a similar trend for in vitro drug release and in vivo pharmacokinetics after intramuscular (IM) injection in rats. In vivo t_max of the IM administered poloxamer in situ forming gels was about 6 h and a short-term sustained drug release was observed in vivo in rats up to 24 h after dosing, similar to a solution of bedaquiline fumarate salt in polyethylene glycol (PEG400)/water. In conclusion, IM administration of the evaluated poloxamer in situ forming gels may be useful for drugs that require a short-term sustained release, but is not able to extend drug release rates up to weeks or months.

Clinical pharmacokinetics, pharmacodynamics, safety, and tolerability of JNJ-54175446, a brain permeable P2X7 antagonist, in a randomised single-ascending dose study in healthy participants

BACKGROUND

Central nervous system-derived interleukin-1β plays a role in mood disorders. P2X7 receptor activation by adenosine-triphosphate leads to the release of interleukin-1β.

AIMS

This first-in-human study evaluated safety, tolerability, pharmacokinetics and pharmacodynamics of a novel central nervous system-penetrant P2X7 receptor antagonist, JNJ-54175446, in healthy participants.

METHODS

The study had three parts: an ascending-dose study in fasted participants (0.5-300 mg JNJ-54175446); an ascending-dose study in fed participants (50-600 mg); and a cerebrospinal fluid study (300 mg). Target plasma concentrations were based on estimated plasma effective concentration (EC)₅₀ (105 ng/mL) and EC₉₀ (900 ng/mL) values for central nervous system P2X7 receptor binding.

RESULTS

Seventy-seven participants received a single oral dose of JNJ-54175446 ( n=59) or placebo ( n=18). Area under the curve of concentration time extrapolated to infinity (AUC_∞) increased dose-proportionally; maximum concentration (C_max) of plasma (C_max,plasma) increased less than dose-proportionally following single doses of JNJ-54175446. Because food increases bioavailability of JNJ-54175446, higher doses were given with food to evaluate safety at higher exposures. The highest C_max,plasma reached (600 mg, fed) was 1475±163 ng/mL. JNJ-54175446 C_max in cerebrospinal fluid, a proxy for brain penetration, was seven times lower than in total plasma; unbound C_max,plasma and C_max,CSF were comparable (88.3±35.7 vs 114±39 ng/mL). JNJ-54175446 inhibited lipopolysaccharide/3'-O-(4-benzoylbenzoyl)-ATP-induced interleukin-1β release from peripheral blood in a dose-dependent manner (inhibitory concentration (IC)₅₀:82 ng/mL; 95% confidence interval: 48-94). Thirty-three of 59 (55.9%) participants reported at least one treatment-emergent adverse event; the most common adverse event being headache (11/59, 18.6%).

CONCLUSION

Plasma exposure of JNJ-54175446 was dose-dependent. No serious adverse events occurred. Single-dose administration of JNJ-54175446>10 mg attenuated ex-vivo lipopolysaccharide-induced interleukin-1β release in peripheral blood. Passive brain penetration of JNJ-54175446 was confirmed.