Pharmacokinetics and pharmacodynamics of mibavademab (a leptin receptor agonist): Results from a first-in-human phase I study.

Mibavademab (previously known as REGN4461), a fully human monoclonal antibody, is being investigated for the treatment of conditions associated with leptin deficiency. Here, we report pharmacokinetics (PKs), pharmacodynamics, and immunogenicity from a phase I study in healthy participants (NCT03530514). In part A, lean or overweight healthy participants were randomized to single-ascending-dose cohorts of 0.3, 1.0, 3.0, 10, and 30 mg/kg intravenous (i.v.), or 300 and 600 mg subcutaneous doses of mibavademab or placebo. In part B, overweight or obese participants were randomized to receive multiple doses of mibavademab (15 mg/kg i.v. loading dose and 10 mg/kg i.v. at weeks 3, 6, and 9) or placebo, stratified by body mass index and baseline leptin levels: low leptin (<5 ng/mL) or relatively low leptin (5-8 ng/mL in men and 5-24 ng/mL in women). Fifty-six and 55 participants completed the single-ascending-dose and multiple-dose parts, respectively. In the single-ascending-dose cohorts, mibavademab PKs were nonlinear with target-mediated elimination, greater than dose-proportional increases in exposure, and there were no dose-dependent differences in total soluble leptin receptor (sLEPR) levels in serum over time. Following multiple-dose administration of mibavademab in participants with leptin <8 ng/mL, lower mean mibavademab concentrations, higher mean total sLEPR concentrations, and larger mean decreases in body weight than in the relatively low leptin cohorts were observed. Baseline leptin was correlated with mibavademab PKs and pharmacodynamics. No treatment-emergent anti-mibavademab antibodies were observed in any mibavademab-treated participant. Results from this study collectively inform further development of mibavademab to treat conditions associated with leptin deficiency.

Evaluating the pharmacokinetics of beclometasone dipropionate/formoterol fumarate/glycopyrronium bromide delivered via pressurised metered-dose inhaler using a low global warming potential propellant.

INTRODUCTION: Use of propellants with high global warming potential (such as HFA-134a) for pressurised metered-dose inhalers (pMDIs) is being phased down. Switching to dry-powder inhalers may not be clinically feasible for all patients; an alternative is reformulation using propellants with low global warming potential. The combination of beclometasone dipropionate/formoterol fumarate/glycopyrronium bromide (BDP/FF/GB) is available for asthma or chronic obstructive pulmonary disease via pMDI using HFA-134a as propellant. This is being reformulated using the low global warming potential propellant HFA-152a. This manuscript reports three studies comparing BDP/FF/GB pharmacokinetics delivered via pMDI using HFA-152a vs HFA-134a. METHODS: The studies were four-way crossover, single-dose, randomised, double-blind, in healthy volunteers. In Studies 1 and 2, subjects inhaled four puffs of BDP/FF/GB (Study 1: 100/6/12.5 µg [medium-strength BDP]; Study 2: 200/6/12.5 µg [high-strength]), ingesting activated charcoal in two of the periods (once per propellant). In Study 3, subjects inhaled medium- and high-strength BDP/FF/GB using a spacer. All three studies compared HFA-152a vs HFA-134a in terms of lung availability and total systemic exposure of beclometasone-17-monopropionate (B17MP; active metabolite of BDP), BDP, formoterol and GB. Bioequivalence was concluded if the 90 % confidence intervals (CIs) of the ratios between formulations of the geometric mean maximum plasma concentration (Cmax) and area under the plasma concentration-time curve between time zero and the last quantifiable timepoint (AUC0-t) for the analytes were between 80 and 125 %. RESULTS: In Studies 1 and 2, systemic exposure bioequivalence (i.e., comparisons without charcoal block) was demonstrated, except for GB Cmax in Study 2 (upper 90 % CI 125.11 %). For lung availability (i.e., comparisons with charcoal block), B17MP and formoterol demonstrated bioequivalence in both studies, as did BDP in Study 2; in Study 1, BDP upper CIs were 126.96 % for Cmax and 127.34 % for AUC0-t). In Study 1, GB AUC0-t lower CI was 74.54 %; in Study 2 upper limits were 135.64 % for Cmax and 129.12 % for AUC0-t. In Study 3, the bioequivalence criteria were met for BDP, B17MP and formoterol with both BDP/FF/GB strengths, and were met for GB AUC0-t, although not for Cmax. Both formulations were similarly well tolerated in all three studies. CONCLUSIONS: Overall, while formal bioequivalence cannot be concluded for all analytes, these data suggest therapeutic equivalence of the new formulation with the existing BDP/FF/GB pMDI formulation, therefore supporting reformulation using a propellant with low global warming potential.

Safety, Tolerability, and Pharmacokinetics of JNJ-1802, a Pan-serotype Dengue Direct Antiviral Small Molecule, in a Phase 1, Double-Blind, Randomized, Dose-Escalation Study in Healthy Volunteers.

BACKGROUND: Dengue is a growing global health threat with no specific antiviral drugs available for treatment or prophylaxis. This first-in-human, double-blind, randomized, placebo-controlled study aimed to examine the safety, tolerability, and pharmacokinetics of increasing single and multiple oral doses of JNJ-1802, a pan-serotype dengue antiviral small molecule. METHODS: Eligible healthy participants (18-55 years of age) were randomized to receive oral JNJ-1802 in fasted conditions as (1) single doses (50-1200 mg; n = 29) or placebo (n = 10); or (2) once-daily doses (50-560 mg for 10 consecutive days or 400 mg for 31 days; n = 38) or placebo (n = 9). Safety and tolerability were evaluated throughout the study. Plasma and urine samples were collected at predetermined time points to characterize pharmacokinetics. RESULTS: JNJ-1802 was generally safe and well-tolerated. One grade 3 adverse event (depression) was reported but not considered drug-related by the investigator. Two grade 2 events of rash occurred (multiple-dose part) that were considered very likely related to JNJ-1802 by the investigator and resolved. No clinically relevant changes were observed in laboratory tests, electrocardiograms, or vital signs.JNJ-1802 exposure after single or multiple doses increased dose-proportionally from 50 to 150 mg and less than dose-proportionally for higher doses. The terminal elimination half-life was 6.3-9.2 days and the accumulation factor was 4.3-7.3 after 10 days and 14.6 after 31 days with low amounts of unchanged drug in urine (<0.001% of the 400 mg dose). CONCLUSIONS: Pharmacokinetics and safety results of JNJ-1802 support further clinical development for the treatment and prevention of dengue infection.

Orally Bioavailable Macrocyclic Peptide That Inhibits Binding of PCSK9 to the Low Density Lipoprotein Receptor.

BACKGROUND: Inhibition of PCSK9 (proprotein convertase subtilisin/kexin type 9)-low density lipoprotein receptor interaction with injectable monoclonal antibodies or small interfering RNA lowers plasma low density lipoprotein-cholesterol, but despite nearly 2 decades of effort, an oral inhibitor of PCSK9 is not available. Macrocyclic peptides represent a novel approach to target proteins traditionally considered intractable to small-molecule drug design. METHODS: Novel mRNA display screening technology was used to identify lead chemical matter, which was then optimized by applying structure-based drug design enabled by novel synthetic chemistry to identify macrocyclic peptide (MK-0616) with exquisite potency and selectivity for PCSK9. Following completion of nonclinical safety studies, MK-0616 was administered to healthy adult participants in a single rising-dose Phase 1 clinical trial designed to evaluate its safety, pharmacokinetics, and pharmacodynamics. In a multiple-dose trial in participants taking statins, MK-0616 was administered once daily for 14 days to characterize the safety, pharmacokinetics, and pharmacodynamics (change in low density lipoprotein cholesterol). RESULTS: MK-0616 displayed high affinity (Ki = 5pM) for PCSK9 in vitro and sufficient safety and oral bioavailability preclinically to enable advancement into the clinic. In Phase 1 clinical studies in healthy adults, single oral doses of MK-0616 were associated with >93% geometric mean reduction (95% CI, 84-103) of free, unbound plasma PCSK9; in participants on statin therapy, multiple-oral-dose regimens provided a maximum 61% geometric mean reduction (95% CI, 43-85) in low density lipoprotein cholesterol from baseline after 14 days of once-daily dosing of 20 mg MK-0616. CONCLUSIONS: This work validates the use of mRNA display technology for identification of novel oral therapeutic agents, exemplified by the identification of an oral PCSK9 inhibitor, which has the potential to be a highly effective cholesterol lowering therapy for patients in need.

Safety and immunogenicity of the measles vector-based SARS-CoV-2 vaccine candidate, V591, in adults: results from a phase 1/2 randomised, double-blind, placebo-controlled, dose-ranging trial.

BACKGROUND: We report on the safety and immunogenicity of V591, a measles vector-based SARS-CoV-2 vaccine candidate. METHODS: In this multicentre, randomised, placebo-controlled, double-blind, phase 1/2 trial, healthy adults with no history of COVID-19 disease were assigned to intramuscular injection of V591 or placebo (4:1 ratio). In part 1, younger adults (18-55 years) received V591 median tissue culture infectious dose (TCID50)-levels of 1×105 or 1×106 or placebo, 56 days apart. In part 2, younger and older (>55 years) adults received a single dose of one of four (104/105/106/107) or one of two (105/106) V591 TCID50 levels, respectively, or placebo. PRIMARY OUTCOME: safety/tolerability. Secondary outcome: humoral immunogenicity. ClinicalTrials.gov: NCT04498247. FINDINGS: From August-December 2020, 444 participants were screened and 263 randomised (210 V591; 53 placebo); 262 received at least one and 10 received two doses of V591 or placebo. Adverse events were experienced by 140/209 (67.0%) V591 dose-group participants and 37/53 (69.8%) placebo-group participants following injection 1; most frequent were fatigue (57 [27.3%] vs 20 [37.7%]), headache (57 [27.3%] vs 19 [35.8%]), myalgia (35 [16.7%] vs 10 [18.9%]), and injection-site pain (35 [16.7%] vs 4 [7.5%]). No deaths nor vaccine-related serious adverse events occurred. At Day 29, no anti-SARS-CoV-2 spike serum neutralising antibody and IgG-responses were identified in placebo or the three lower V591 dose-groups; responses were detected with V591 1×107 TCID50, although titres were lower than convalescent serum. INTERPRETATION: V591 was generally well tolerated, but immunogenicity was insufficient to warrant continued development. FUNDING: Merck Sharp & Dohme, Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.

A Randomized, Double-Blind, Placebo-Controlled, Multiple Dose Escalation Study to Evaluate the Safety and Pharmacokinetics of ELX-02 in Healthy Subjects.

ELX-02 is an investigational compound being developed as a therapy for genetic diseases caused by nonsense mutations such as cystic fibrosis. Structurally, ELX-02 is an aminoglycoside analogue that induces read-through of nonsense mutations through interaction with the ribosome, resulting in the production of full-length functional proteins. This phase 1 multiple-ascending-dose trial evaluated the safety and pharmacokinetics of ELX-02 in 62 healthy volunteers. ELX-02 plasma exposure was dose proportional, with no apparent accumulation, and followed by renal elimination. The most reported adverse event was injection site reactions that were mild to moderate in severity. At the top dose of 5.0 mg/kg, 1 of 6 subjects experienced auditory threshold changes in which ototoxicity could not be clearly ruled out, and 2 of 6 had hearing threshold changes consistent with possible ototoxicity. Two of 3 subjects receiving placebo in the 5.0 mg/kg group also had significant hearing threshold changes. All observed hearing threshold changes resolved or were trending toward resolution after withdrawal of the study drug. No severe or serious adverse events were reported.The results of this study support the evaluation of ELX-02 in phase 2 clinical trials with patients that have genetic diseases caused by nonsense mutations.

Pharmacokinetics and Pharmacodynamics of Garetosmab (Anti-Activin A): Results From a First-in-Human Phase 1 Study.

We describe outcomes from the first-in-human study of garetosmab (a fully human monoclonal antibody that inhibits activin A) under development for the treatment of fibrodysplasia ossificans progressiva (FOP). In a double-blind, placebo-controlled phase 1 study, 40 healthy women of nonchildbearing potential were randomized to receive a single dose of intravenous garetosmab 0.3, 1, 3, or 10 mg/kg; subcutaneous garetosmab 300 mg; or placebo. Serum concentrations of functional garetosmab (with ≥1 arm free to bind to target), total activin A, and antidrug antibodies were measured predose and up to 113 days post-first dose. Garetosmab demonstrated an acceptable safety profile with no dose-limiting toxicities. Garetosmab displayed nonlinear pharmacokinetics with target-mediated elimination. With increasing doses of intravenous garetosmab, mean peak concentration increased in a dose-proportional manner; mean steady-state estimates ranged from 41.4 to 47.8 mL/kg. A greater than dose-proportional increase in mean area under the concentration-time curve from time zero extrapolated to infinity (range, 72.2-7520 mg*day/L) was observed, consistent with decreasing mean clearance (range, 4.35-1.34 mL/day/kg). Following administration of intravenous garetosmab, mean concentrations of total activin A increased in a dose-dependent manner. At 10 mg/kg, total activin A levels reached a state of little or no change between weeks 4 and 12, suggesting saturation of the target-mediated pathway. No safety signals were seen in this study to preclude investigation in patients. Following intravenous administration, garetosmab concentrations decreased quickly, then decreased over time (reflecting linear elimination), and finally decreased in a nonlinear phase, reflecting target-mediated elimination. Results here support further investigation. Garetosmab 10 mg/kg every 4 weeks intravenously is being evaluated in patients with FOP (NCT03188666).

Randomized study of the effect of gadopiclenol, a new gadolinium-based contrast agent, on the QTc interval in healthy subjects.

AIMS: We investigated the effect of gadopiclenol, a new gadolinium-based contrast agent, on the QTc interval at clinical and supraclinical dose, considering the relative hyperosmolarity of this product. METHODS: This was a single centre, randomized, double-blind, placebo- and positive-controlled, 4-way crossover study. Forty-eight healthy male and female subjects were included to receive single intravenous (i.v.) administrations of gadopiclenol at the clinical dose of 0.1 mmol kg-1 , standard for current gadolinium-based contrast agents, the supraclinical dose of 0.3 mmol kg-1 , placebo and a single oral dose of 400 mg moxifloxacin. RESULTS: The largest time-matched placebo-corrected, mean change from-baseline in QTcF (ΔΔQTcF) was observed 3 hours after administration of 0.1 mmol kg-1 gadopiclenol (2.39 ms, 90% confidence interval [CI]: 0.35, 4.43 ms) and 5 minutes after administration of 0.3 mmol kg-1 (4.81 ms, 90%CI: 2.84, 6.78 ms). The upper limit of the 90% CI was under the threshold of 10 ms, demonstrating no significant effect of gadopiclenol on QTc interval. From 1.5 to 4 hours postdose moxifloxacin, the lower limit of the 90% CI of ΔΔQTcF exceeded 5 ms demonstrating assay sensitivity. Although there was a positive slope, the concentration-response analysis estimated that the values of ΔΔQTcF at the maximal concentration of gadopiclenol at 0.1 and 0.3 mmol kg-1 were 0.41 and 2.23 ms, respectively, with the upper limit of the 90% CI not exceeding 10 ms. No serious or severe adverse events or treatment discontinuations due to adverse events were reported. CONCLUSION: This thorough QT/QTc study demonstrated that gadopiclenol did not prolong the QT interval at clinical and supraclinical doses and was well tolerated in healthy volunteers. The positive slope of the QTc prolongation vs concentration relationship suggests that hyperosmolarity could be associated with QTc prolongation. However, the amplitude of this effects is unlikely to be associated with proarrhythmia.

Safety, pharmacokinetics and antiviral activity of AT-527, a novel purine nucleotide prodrug, in HCV-infected subjects with and without cirrhosis.

AT-527 is a novel modified guanosine nucleotide prodrug inhibitor of the hepatitis C virus (HCV) NS5B polymerase, with increased in vitro antiviral activity as compared to sofosbuvir and a highly differentiated favorable preclinical profile compared to other anti-HCV nucleoside/nucleotide analogs. This was a multiple part clinical study where multiple ascending doses of AT-527 up to 600 mg (expressed as AT-527 salt form; equivalent to 553 mg free base) once daily for seven days were evaluated in a randomized, double-blind, placebo-controlled study of treatment-naïve, non-cirrhotic, genotype 1b, HCV-infected subjects. The highest dose of AT-527 for the same duration was then evaluated in two open label cohorts of a) non-cirrhotic, genotype 3, HCV-infected subjects and b) HCV-infected subjects of any genotype with compensated (Child-Pugh A) cirrhosis. AT-527 was well tolerated for seven days in all cohorts. At the highest dose tested, mean HCV RNA reductions of up to 2.4 log10 IU/mL occurred within the first 24 hours of dosing. Mean maximum reductions observed with seven days of dosing were 4.4, 4.5 and 4.6 log10 IU/mL in non-cirrhotic subjects with HCV genotype 1b, non-cirrhotic subjects with HCV genotype 3, and subjects with compensated cirrhosis, respectively. The systemic half-life of AT-273, the nucleoside metabolite considered a surrogate of intracellular phosphates including the active triphosphate, exceeded 20 hours, supporting once daily dosing. In summary, AT-527 demonstrated rapid, potent, dose/exposure-related and pan-genotypic antiviral activity with similar responses between subjects with and without cirrhosis. Exposure-antiviral response analysis identified 550 mg (free base equivalent) as the optimal dose of AT-527. Safety and antiviral activity data from this study warrant continued clinical development of AT-527 dosed once daily.

Safety, Tolerability, and Pharmacokinetics of Single Ascending Doses of ELX-02, a Potential Treatment for Genetic Disorders Caused by Nonsense Mutations, in Healthy Volunteers.

ELX-02 is an investigational synthetic eukaryotic ribosome-selective glycoside optimized as a translational read-through molecule that induces read through of nonsense mutations, resulting in normally localized full-length functional proteins. ELX-02 is being developed as a therapy for genetic diseases caused by nonsense mutations. Two phase 1a, randomized, double-blind placebo-controlled, single-ascending-dose studies were conducted in healthy human subjects to evaluate the safety and pharmacokinetics of ELX-02. Single subcutaneously injected doses of ELX-02 between 0.3 mg/kg and 7.5 mg/kg showed an acceptable safety profile without severe or serious drug-related adverse events, including a lack of renal and ototoxicity events. Injection of ELX-02 resulted in a rapid time to peak concentration and elimination phase, with complete elimination from the vascular compartment within 10 hours. ELX-02 area under the concentration-time curve to infinity showed dose-exposure linearity (24-fold increase for a 25-fold dose increase), and the maximum concentration showed dose proportionality (17-fold increase for a 25-fold increase). The mean apparent volume of distribution was dose dependent, suggesting an increased distribution and tissue uptake of ELX-02 at higher doses. The primary route of excretion was in the urine, with the majority of the compound excreted unchanged. These results support the evaluation of the safety, pharmacokinetics, and efficacy of repeat dosing in future studies.

Sputum induction for assessment of biomarkers in early respiratory drug development
.

OBJECTIVE: To study the success rate and reproducibility of sputum induction (SI) in healthy subjects (HS) and asthma patients (AP). MATERIALS AND METHODS: 130 HSs/APs were recruited for early-phase studies to evaluate sputum biomarkers. SI and sample processing were performed according to standard protocols. RESULTS: Adequate samples were obtained from 46% of HSs and 80% of APs. There was no difference between the groups with adequate and nonadequate samples. Differences between HS and AP groups were minor. Reproducibility was 56.0% in HSs and 90.6% in APs. CONCLUSION: Sputum induction for biomarker assessment in early drug development is feasible in HSs and APs, but only modestly reproducible in HSs. The technique is complex and time consuming.
.

Efficacy, Safety, Pharmacokinetics, and Pharmacodynamics of Filgotinib, a Selective JAK-1 Inhibitor, After Short-Term Treatment of Rheumatoid Arthritis: Results of Two Randomized Phase IIa Trials.

OBJECTIVE: JAK inhibitors have shown efficacy in rheumatoid arthritis (RA). We undertook this study to test our hypothesis that selective inhibition of JAK-1 would combine good efficacy with a better safety profile compared with less selective JAK inhibitors. METHODS: In two 4-week exploratory, double-blind, placebo-controlled phase IIa trials, 127 RA patients with an insufficient response to methotrexate (MTX) received filgotinib (GLPG0634, GS-6034) oral capsules (100 mg twice daily or 30, 75, 150, 200, or 300 mg once daily) or placebo, added onto a stable regimen of MTX, to evaluate safety, efficacy, pharmacokinetics (PK), and pharmacodynamics (PD) of filgotinib. The primary efficacy end point was the number and percentage of patients in each treatment group meeting the American College of Rheumatology 20% improvement criteria (achieving an ACR20 response) at week 4. RESULTS: Treatment with filgotinib at 75-300 mg met the primary end point and showed early onset of efficacy. ACR20 response rates progressively increased to week 4, and the Disease Activity Score in 28 joints using the C-reactive protein (CRP) level decreased. Marked and sustained improvements were observed in serum CRP level and other PD markers. The PK of filgotinib and its major metabolite was dose proportional over the 30-300 mg range. Early side effects seen with other less selective JAK inhibitors were not observed (e.g., there was no worsening of anemia [JAK-2 inhibition related], no effects on liver transaminases, and no increase in low-density lipoprotein or total cholesterol). A limited decrease in neutrophils without neutropenia was consistent with immunomodulatory effects through JAK-1 inhibition. There were no infections. Overall, filgotinib was well tolerated. Events related to study drug were mild or moderate and transient during therapy, and the most common such event was nausea. CONCLUSION: Selective inhibition of JAK-1 with filgotinib shows initial efficacy in RA with an encouraging safety profile in these exploratory studies.

Safety, pharmacokinetics and pharmacodynamics of GLPG0974, a potent and selective FFA2 antagonist, in healthy male subjects.

AIMS: Free fatty acids (FFA) can act as direct signalling molecules through activation of several membrane-bound G-protein coupled receptors. The FFA2 receptor (known as GPR43) is activated by short chain fatty acids (SCFA) such as acetate and has been shown to play a major role in SCFA-induced neutrophil activation and migration and to contribute in the development and control of inflammation. GLPG0974 is a potent and selective antagonist of the human FFA2. The main objectives of the two phase 1 trials were to characterize the safety, tolerability, pharmacokinetics and pharmacodynamics of GLPG0974. METHODS: Two consecutive randomized, double-blind, placebo-controlled, single centre trials in healthy subjects were performed. In the first, GLPG0974 was administered as single doses up to 250 mg and in the second, multiple daily doses up to 400 mg for 14 days were evaluated. Non-compartmental analysis was used to determine GLPG0974 pharmacokinetics while target engagement was investigated through the inhibition of neutrophils in acetate-simulated whole blood samples using surface expression of CD11b activated epitope as a marker of neutrophil activation. RESULTS: The investigation of safety/tolerability and pharmacokinetics in the early development phase showed that GLPG0974 was safe and well tolerated up to a daily dose of 400 mg. GLPG0974 showed good and dose proportional exposure up to 400 mg daily as well as a substantial and sustained inhibition of acetate-stimulated neutrophil activation. CONCLUSION: Based on these results, a proof-of-concept study was initiated to evaluate the safety, tolerability and efficacy of GLPG0974 in patients with mild to moderate ulcerative colitis.

A dose escalating phase I study of GLPG0187, a broad spectrum integrin receptor antagonist, in adult patients with progressive high-grade glioma and other advanced solid malignancies.

BACKGROUND: Integrin signaling is an attractive target for anti-cancer treatment. GLPG0187 is a broad spectrum integrin receptor antagonist (IRA). GLPG0187 inhibited tumor growth and metastasis in mouse models. METHODS: We aimed to determine the Recommended Phase II Dose (RP2D) and to assess safety and tolerability of continuous i.v. infusion in patients with advanced malignant solid tumors. Anticipated dose levels were 20, 40, 80, 160, 320, and 400 mg/day in a modified 3 + 3 design. Plasma concentrations of GLPG0187 were assessed to characterize the pharmacokinetics (PK). C-terminal telopeptide of type I collagen (CTX) was used as pharmacodynamics marker. RESULTS: Twenty patients received GLPG0187. No dose limiting toxicities (DLTs) were observed. The highest possible and tested dose was 400 mg/day. Fatigue was the most frequently reported side effect (25%). Recurrent Port-A-Cath-related infections and skin toxicity suggest cutaneous integrin inhibition. No dose-dependent toxicity could be established. PK analysis showed a short average distribution (0.16 h) and elimination (3.8 h) half-life. Continuous infusion resulted in dose proportional PK profiles. We observed decreases in serum CTX levels independent of the dose given, suggesting target engagement at the lowest dose level tested. Single agent treatment did not result in tumor responses. CONCLUSIONS: GLPG0187 was well tolerated with a dose-proportional PK profile upon continuous infusion. No formal maximal tolerated dose could be established. GLPG0187 showed signs of target engagement with a favourable toxicity profile. However, continuous infusion of GLPG0187 failed to show signs of monotherapy efficacy.

Oral administration of GLPG0259, an inhibitor of MAPKAPK5, a new target for the treatment of rheumatoid arthritis: a phase II, randomised, double-blind, placebo-controlled, multicentre trial.

BACKGROUND: Mitogen-activated protein (MAP) kinases are key regulators of cytokine production, and are therefore potential targets for treatment of rheumatoid arthritis (RA). OBJECTIVE: This two-part phase II study investigated the efficacy and safety of a once-daily 50 mg GLPG0259 (an inhibitor of MAP kinase-activated protein kinase 5) dose vs placebo (part A). An interim analysis after part A would determine whether the dose-finding part (part B) would be performed. METHODS: In part A, eligible methotrexate (MTX)-refractory patients with RA were randomised to receive either a once-daily 50 mg dose of GLPG0259 or placebo, in addition to a stable dose of MTX, for 12 weeks. The primary efficacy end point was the percentage of patients achieving an American College of Rheumatology 20% improvement (ACR20) response after 12 weeks. RESULTS: The interim analysis showed no difference between the percentage of subjects achieving the primary efficacy variable of ACR20 or the secondary efficacy variables (ACR50, ACR70 and Disease Activity Score 28) at week 12 in the GLPG0259-treated (n=19) and placebo-treated (n=11) groups. Owing to lack of efficacy, the study was terminated, and part B was not initiated. CONCLUSIONS: This innovative study design quickly provided conclusive results on the lack of efficacy of GLPG0259 in patients with RA.

Pharmacokinetics, safety, and tolerability of GLPG0259, a mitogen-activated protein kinase-activated protein kinase 5 (MAPKAPK5) inhibitor, given as single and multiple doses to healthy male subjects.

BACKGROUND AND OBJECTIVES: GLPG0259 is a small-molecule inhibitor of mitogen-activated protein kinase-activated protein kinase 5 (MAPKAPK5), a kinase enzyme that plays a role in important inflammatory pathways. The main objectives of the phase I clinical studies in early development were to characterize the pharmacokinetics, tolerability, and safety of GLPG0259 in healthy subjects, including the development of a solid dosage form (free-base pellets and fumarate salt capsules) and the potential for interaction of GLPG0259 with methotrexate. SUBJECTS AND METHODS: Four phase I studies were initiated. Study 1 was a randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, and pharmacokinetics of single ascending doses (1.5-150 mg) and multiple oral doses (20 and 50 mg once daily) of GLPG0259 in healthy male subjects (n = 34). Study 2 was a randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, and pharmacokinetics of oral multiple ascending doses of GLPG0259 (25-75 mg once daily) given for 14 days to healthy male subjects, and to get preliminary information on the potential pharmacokinetic interaction between GLPG0259 and methotrexate (n = 24). Studies 3 and 4 were open-label, randomized, crossover studies to compare the oral bioavailability of two solid dosage forms of GLPG0259 (a capsule) relative to an oral solution after a 100 mg or 50 mg single dose and to evaluate the effect of food on these formulations (n = 12 for each study). MAIN OUTCOME MEASURES: The non-compartmental pharmacokinetic parameters for plasma concentrations of GLPG0259 were determined, and a population pharmacokinetic model of GLPG0259 was developed to support the planning of the number and timing of the sparse samples to be taken per patient in the phase II study. Safety and tolerability data are also summarized. RESULTS: The absorption of GLPG0259 was slow, with a decrease in the absorption rate with increasing dose, and there was decreased elimination, with an apparent terminal elimination half-life of 26.0 hours. On the basis of statistical analysis of variance, the exposure to GLPG0259 increased in proportion to the dose over a 30-150 mg single-dose range and a 25-75 mg repeated-dose range. Between- and within-subject variability in GLPG0259 pharmacokinetics was low/moderate (coefficient of variation [CV] 16-30%). After once-daily repeated dosing, steady-state plasma concentrations were reached at between 5 and 8 dosing days, which is consistent with the long apparent elimination half-life of GLPG0259. Food increased the bioavailability of GLPG0259 given in a solid dosage form. Co-administration of GLPG0259 with a single dose of methotrexate 7.5 mg did not result in any change in the pharmacokinetic profiles of either GLPG0259 or methotrexate. CONCLUSION: In summary, the investigation of safety/tolerability and pharmacokinetics in the early development phase showed that single and repeated doses of GLPG0259 were safe and well tolerated. The most common adverse event reported was mild gastrointestinal discomfort. The pharmacokinetics characterized in healthy male subjects showed no major obstacles and supports a once-daily oral regimen in patients.

Correlations between factors determining the pharmacokinetics and antiviral activity of HIV-1 non-nucleoside reverse transcriptase inhibitors of the diaryltriazine and diarylpyrimidine classes of compounds.

OBJECTIVE: To investigate the important factors that determine the bioavailability and the antiviral activity of the diaryltriazine (DATA) and diarylpyrimidine (DAPY) non-nucleoside reverse transcriptase inhibitors (NNRTIs) of HIV-1 in animal species and humans using cell-based assays, physicochemical and computed parameters. METHODS: This naturalistic study included 15 parameters ranging from molecular mechanics calculations to phase I clinical trials. The calculated parameters were solvent-accessible surface area (SASA), polar surface area and Gibbs free energy of solvation. Physicochemical parameters comprised lipophilicity (octanol/water partition coefficient [cLogP]), ionisation constant (pKa), solubility and aggregate radius. Cell-based assays included human colonic adenocarcinoma cell (Caco-2) permeability (transepithelial transport), drug metabolism and antiviral activity (negative logarithm of the molar effective concentration inhibiting viral replication by 50% [pEC50]). Exposure was tested in rats, dogs and human volunteers. RESULTS: Of the 15 parameters, eight correlated consistently among one another. Exposure (area under the plasma concentration-time curve [AUC]) in humans correlated positively with that in rats (r = 1.00), with transepithelial transport (r = 0.83), lipophilicity (r = 0.60), ionisability (r = 0.89), hydrodynamic radius of aggregates (r = 0.66) and with antiviral activity (r = 0.61). Exposure in humans was also seen to correlate negatively with SASA (r = -0.89). No consistent correlation was found between exposure in dogs and the eight parameters. Of the 14 DATA/DAPY molecules, 11 form aggregates with radii between 34 and 100 nm. CONCLUSIONS: We observed correlations between exposure in humans with exposure in rats, transepithelial transport (Caco-2 cells), ionisability, lipophilicity, aggregate radius and SASA in the class of DATA/DAPY NNRTI compounds. The lipophilic DATA/DAPY compounds form aggregates. It can be assumed that absorption in the intestinal tract and endocytosis in infected cells of these lipophilic compounds are governed by the common phenomenon of aggregate formation. As the lymphatic system offers a pathway for intestinal uptake of aggregates, this may offer a therapeutic advantage in the treatment of HIV-1 infection. Although it was not the objective of the study, we found that the rat was a better in vivo model than the dog for the prediction of systemic exposure in this particular set of compounds.