Drug-drug interaction prediction of ziritaxestat using a physiologically based enzyme and transporter pharmacokinetic network interaction model.

Ziritaxestat, an autotaxin inhibitor, was under development for the treatment of idiopathic pulmonary fibrosis. It is a substrate of cytochrome P450 3A4 (CYP3A4) and P-glycoprotein and a weak inhibitor of the CYP3A4 and OATP1B1 pathways. We developed a physiologically based pharmacokinetic (PBPK) network interaction model for ziritaxestat that incorporated its metabolic and transporter pathways, enabling prediction of its potential as a victim or perpetrator of drug-drug interactions (DDIs). Concurrently, we evaluated CYP3A4 autoinhibition, including time-dependent inhibition. In vitro information and clinical data from healthy volunteer studies were used for model building and validation. DDIs with rifampin, itraconazole, voriconazole, pravastatin, and rosuvastatin were predicted, followed by validation against a test dataset. DDIs of ziritaxestat as a victim or perpetrator were simulated using the final model. Predicted-to-observed DDI ratios for the maximum plasma concentration (Cmax ) and the area under the plasma concentration-time curve (AUC) were within a two-fold ratio for both the metabolic and transporter-mediated simulated DDIs. The predicted impact of autoinhibition/autoinduction or time-dependent inhibition of CYP3A4 was a 12% decrease in exposure. Model-based predictions for ziritaxestat as a victim of DDIs with a moderate CYP3A4 inhibitor (fluconazole) suggested a 2.6-fold increase in the AUC of ziritaxestat, while multiple doses of a strong inhibitor (voriconazole) would increase the AUC by 15-fold. Efavirenz would yield a three-fold decrease in the AUC of ziritaxestat. As a perpetrator, ziritaxestat was predicted to increase the AUC of the CYP3A4 index substrate midazolam by 2.7-fold. An overarching PBPK model was developed that could predict DDI liability of ziritaxestat for both CYP3A4 and the transporter pathways.

Ziritaxestat, a Novel Autotaxin Inhibitor, and Lung Function in Idiopathic Pulmonary Fibrosis: The ISABELA 1 and 2 Randomized Clinical Trials.

Importance: There is a major need for effective, well-tolerated treatments for idiopathic pulmonary fibrosis (IPF). Objective: To assess the efficacy and safety of the autotaxin inhibitor ziritaxestat in patients with IPF. Design, Setting, and Participants: The 2 identically designed, phase 3, randomized clinical trials, ISABELA 1 and ISABELA 2, were conducted in Africa, Asia-Pacific region, Europe, Latin America, the Middle East, and North America (26 countries). A total of 1306 patients with IPF were randomized (525 patients at 106 sites in ISABELA 1 and 781 patients at 121 sites in ISABELA 2). Enrollment began in November 2018 in both trials and follow-up was completed early due to study termination on April 12, 2021, for ISABELA 1 and on March 30, 2021, for ISABELA 2. Interventions: Patients were randomized 1:1:1 to receive 600 mg of oral ziritaxestat, 200 mg of ziritaxestat, or placebo once daily in addition to local standard of care (pirfenidone, nintedanib, or neither) for at least 52 weeks. Main Outcomes and Measures: The primary outcome was the annual rate of decline for forced vital capacity (FVC) at week 52. The key secondary outcomes were disease progression, time to first respiratory-related hospitalization, and change from baseline in St George's Respiratory Questionnaire total score (range, 0 to 100; higher scores indicate poorer health-related quality of life). Results: At the time of study termination, 525 patients were randomized in ISABELA 1 and 781 patients in ISABELA 2 (mean age: 70.0 [SD, 7.2] years in ISABELA 1 and 69.8 [SD, 7.1] years in ISABELA 2; male: 82.4% and 81.2%, respectively). The trials were terminated early after an independent data and safety monitoring committee concluded that the benefit to risk profile of ziritaxestat no longer supported their continuation. Ziritaxestat did not improve the annual rate of FVC decline vs placebo in either study. In ISABELA 1, the least-squares mean annual rate of FVC decline was -124.6 mL (95% CI, -178.0 to -71.2 mL) with 600 mg of ziritaxestat vs -147.3 mL (95% CI, -199.8 to -94.7 mL) with placebo (between-group difference, 22.7 mL [95% CI, -52.3 to 97.6 mL]), and -173.9 mL (95% CI, -225.7 to -122.2 mL) with 200 mg of ziritaxestat (between-group difference vs placebo, -26.7 mL [95% CI, -100.5 to 47.1 mL]). In ISABELA 2, the least-squares mean annual rate of FVC decline was -173.8 mL (95% CI, -209.2 to -138.4 mL) with 600 mg of ziritaxestat vs -176.6 mL (95% CI, -211.4 to -141.8 mL) with placebo (between-group difference, 2.8 mL [95% CI, -46.9 to 52.4 mL]) and -174.9 mL (95% CI, -209.5 to -140.2 mL) with 200 mg of ziritaxestat (between-group difference vs placebo, 1.7 mL [95% CI, -47.4 to 50.8 mL]). There was no benefit with ziritaxestat vs placebo for the key secondary outcomes. In ISABELA 1, all-cause mortality was 8.0% with 600 mg of ziritaxestat, 4.6% with 200 mg of ziritaxestat, and 6.3% with placebo; in ISABELA 2, it was 9.3% with 600 mg of ziritaxestat, 8.5% with 200 mg of ziritaxestat, and 4.7% with placebo. Conclusions and Relevance: Ziritaxestat did not improve clinical outcomes compared with placebo in patients with IPF receiving standard of care treatment with pirfenidone or nintedanib or in those not receiving standard of care treatment. Trial Registration: ClinicalTrials.gov Identifiers: NCT03711162 and NCT03733444.

GLPG1205 for idiopathic pulmonary fibrosis: a phase 2 randomised placebo-controlled trial.

BACKGROUND: GLPG1205 is a selective functional antagonist of G-protein-coupled receptor 84, which plays an important role in fibrotic processes. This study assessed the efficacy, safety and tolerability of GLPG1205 for treatment of idiopathic pulmonary fibrosis (IPF). METHODS: PINTA (ClinicalTrials.gov: NCT03725852) was a phase 2, randomised, double-blind, placebo-controlled, proof-of-concept trial. Patients with IPF were randomised 2:1 to once-daily oral GLPG1205 100 mg or placebo for 26 weeks and stratified to receive GLPG1205 alone or with local standard of care (nintedanib or pirfenidone). The primary end-point was change from baseline in forced vital capacity (FVC); other end-points were safety and tolerability, and lung volumes measured by imaging (high-resolution computed tomography). The study was not powered for statistical significance. RESULTS: In total, 68 patients received study medication. Least squares mean change from baseline in FVC at week 26 was -33.68 (95% CI -112.0-44.68) mL with GLPG1205 and -76.00 (95% CI -170.7-18.71) mL with placebo (least squares mean difference 42.33 (95% CI -81.84-166.5) mL; p=0.50). Lung volumes by imaging declined -58.30 versus -262.72 mL (whole lung) and -33.68 versus -135.48 mL (lower lobes) with GLPG1205 versus placebo, respectively. Treatment with GLPG1205 versus placebo resulted in higher proportions of serious and severe treatment-emergent adverse events and treatment-emergent discontinuations, most apparent with nintedanib. CONCLUSIONS: Treatment with GLPG1205 did not result in a significant difference in FVC decline versus placebo. GLPG1205 demonstrated a poorer safety and tolerability profile than placebo.

Ziritaxestat Drug-Drug Interaction with Oral Contraceptives: Role of SULT1E1 Inhibition.

In vitro signals indicate that ziritaxestat is a weak cytochrome P450 (CYP) 3A4 inhibitor and inducer. Therefore, potential drug-drug interactions (DDIs) with oral contraceptives were examined at a time when ziritaxestat was under development for treatment of fibrotic diseases. This open-label, crossover (fixed sequence) DDI study enrolled healthy, nonpregnant women aged 18-65 years (n = 15) who were using highly effective contraception, such as a nonhormonal intrauterine device, bilateral tubal occlusion, or sexual abstinence. A single dose of oral contraceptive (0.03 mg ethinyl estradiol (EE) and 3 mg drospirenone (DRSP)) was administered on days 1, 8, and 18, and ziritaxestat 600 mg once daily was administered from days 8 to 23. Co-administration resulted in a 2.8-fold and 2.4-fold increase in EE maximum plasma concentration (Cmax ) and area under the plasma drug concentration-time curve from time zero to infinity (AUC0-inf ), respectively (day 18 vs. day 1). DRSP Cmax and AUC0-inf increased by 1.1-fold and 1.2-fold, respectively. DRSP is a CYP3A4 substrate, meaning increased EE exposure with ziritaxestat was not due to CYP3A4 inhibition. Ziritaxestat inhibition of EE glucuronidation and sulfation was quantified by liquid chromatography with tandem mass spectrometry in day 1 and day 18 plasma samples after EE conjugate hydrolysis. The ratio of EE AUC from time of administration up to the time of the last quantifiable concentration (AUClast ) with/without hydrolysis by arylsulfatase was substantially lower on day 18 vs. day 1, suggesting ziritaxestat is a potent inhibitor of sulfation; EE glucuronidation was largely unaffected by ziritaxestat. In vitro assessment confirmed ziritaxestat is a potent inhibitor of sulfotransferase family 1E member 1 (half-maximal inhibitory concentration < 0.8 µM). These findings highlight the importance of assessing enzymes other than CYP3A4 when investigating potential DDIs with oral contraceptives.

Pharmacokinetics and Metabolism of Ziritaxestat (GLPG1690) in Healthy Male Volunteers Following Intravenous and Oral Administration.

Ziritaxestat is a novel inhibitor of autotaxin, an enzyme responsible for the production of lysophosphatidic acid, the downstream signaling of which mediates responses to tissue injury and has been implicated in the pathogenesis of fibrotic conditions such as idiopathic pulmonary fibrosis and systemic sclerosis. This study (Clinical Trial Registration: NCT03787186) was designed to assess the absorption, distribution, metabolism, and excretion of orally administered 600-mg ziritaxestat labeled with a carbon-14 tracer (14 C-ziritaxestat). To understand the absolute bioavailability of ziritaxestat, an intravenous 100-µg microdose, labeled with a microtracer amount of 14 C radiation, was administered in a separate part of the study, following an unlabeled 600-mg therapeutic oral dose of ziritaxestat. Six healthy male subjects completed each study part. The majority of the labeled oral dose was recovered in feces (77%), with a total mass balance of 84%. The absolute bioavailability of ziritaxestat was 54%. Ziritaxestat was the main (76%) circulating drug-related product. There were 7 treatment-emergent adverse events, all of which were considered mild and not considered to be related to the study drug.

GLPG1205, a GPR84 Modulator: Safety, Pharmacokinetics, and Pharmacodynamics in Healthy Subjects.

GLPG1205 is a modulator of GPR84, a G-protein-coupled receptor reported to be associated with several diseases. Safety, tolerability, pharmacokinetics, and pharmacodynamics of GLPG1205 in healthy subjects were evaluated in 2 randomized, double-blind, placebo-controlled, single-site, phase 1 studies. In study 1, 16 (aged 21-48 years) and 24 (24-50 years) healthy men received single doses of GLPG1205 10 to 800 mg, and GLPG1205 50, 100, or 200 mg once daily for 14 days, respectively, or placebo. Study 2 evaluated the effect of aging on GLPG1205 pharmacokinetics: 24 healthy men (aged 37-83 years), weight-matched into 3 age cohorts (65-74, ≥75, and 18-50 years), received GLPG1205 50 mg or placebo once daily for 14 days; an open-label part of this study evaluated a GLPG1205 250-mg loading dose followed by 50 mg once daily for 13 days in 8 healthy men (aged 68-74 years). Single (up to 800 mg) and multiple (maximum tolerated dose 100 mg once daily) GLPG1205 doses had favorable safety and tolerability profiles. After single administration of GLPG1205, median time to occurrence of maximum observed plasma concentration and arithmetic mean apparent terminal half-life ranged from 2.0 to 4.0 and from 30.1 to 140 hours, respectively. Age did not affect GLPG1205 exposure. GPR84 receptor occupancy with GLPG1205 vs placebo confirmed target engagement. These results support further clinical development of GLPG1205.

Effect of GLPG1205, a GPR84 Modulator, on CYP2C9, CYP2C19, and CYP1A2 Enzymes: In Vitro and Phase 1 Studies.

GLPG1205 is a novel agent being investigated for the treatment of idiopathic pulmonary fibrosis. GLPG1205 may be concomitantly administered with pirfenidone in future clinical development; therefore, the potential for GLPG1205 to interact with enzymes involved in the metabolism of pirfenidone (cytochrome P450 [CYP] 1A2, CYP2C9, 2C19) was evaluated. In vitro experiments indicated weak inhibition of CYP1A2 and moderate but reversible inhibition of CYP2C9 and CYP2C19 by GLPG1205. A phase 1 randomized, double-blind crossover study in 14 healthy males (NCT02623296) evaluated the effect of GLPG1205 100 mg or placebo (once daily for 12 days) on the single-dose pharmacokinetics of a cocktail of CYP1A2, CYP2C9, and CYP2C19 substrates (coadministered on day 13). GLPG1205 had no effect on the exposure of CYP2C9 and CYP1A2 substrates or metabolites; however, a trend toward increased omeprazole (CYP2C19 substrate) exposure was observed. Although considered not clinically relevant, GLPG1205 increased the elimination rate of 5-hydroxyomeprazole (CYP2C19 metabolite) 1.16-fold versus placebo. GLPG1205 had no effect on the elimination of all other substrates or metabolites. GLPG1205 had a favorable safety and tolerability profile. In conclusion, GLPG1205 100 mg once daily does not interact with CYP2C9, CYP2C19, or CYP1A2 to a clinically relevant extent and may be administered concomitantly with drugs metabolized by these enzymes.

A phase 2 randomized, double-blind, placebo-controlled, proof-of-concept study of oral seletalisib in primary Sjögren's syndrome.

OBJECTIVES: This phase 2 proof-of-concept study (NCT02610543) assessed efficacy, safety and effects on salivary gland inflammation of seletalisib, a potent and selective PI3Kδ inhibitor, in patients with moderate-to-severe primary Sjögren's syndrome (PSS). METHODS: Adults with PSS were randomized 1:1 to seletalisib 45 mg/day or placebo, in addition to current PSS therapy. Primary end points were safety and tolerability and change from baseline in EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) score at week 12. Secondary end points included change from baseline at week 12 in EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) score and histological features in salivary gland biopsies. RESULTS: Twenty-seven patients were randomized (seletalisib n = 13, placebo n = 14); 20 completed the study. Enrolment challenges led to early study termination with loss of statistical power (36% vs 80% planned). Nonetheless, a trend for improvement in ESSDAI and ESSPRI [difference vs placebo: -2.59 (95% CI: -7.30, 2.11; P=0.266) and -1.55 (95% CI: -3.39, 0.28), respectively] was observed at week 12. No significant changes were seen in saliva and tear flow. Serious adverse events (AEs) were reported in 3/13 of patients receiving seletalisib vs 1/14 for placebo and 5/13 vs 1/14 discontinued due to AEs, respectively. Serum IgM and IgG concentrations decreased in the seletalisib group vs placebo. Seletalisib demonstrated efficacy in reducing size and organisation of salivary gland inflammatory foci and in target engagement, thus reducing PI3K-mTOR signalling compared with placebo. CONCLUSION: Despite enrolment challenges, seletalisib demonstrated a trend towards clinical improvement in patients with PSS. Histological analyses demonstrated encouraging effects of seletalisib on salivary gland inflammation and organisation. TRIAL REGISTRATION: https://clinicaltrials.gov, NCT02610543.

Seletalisib for Activated PI3Kδ Syndromes: Open-Label Phase 1b and Extension Studies.

Mutations in two genes can result in activated PI3Kδ syndrome (APDS), a rare immunodeficiency disease with limited therapeutic options. Seletalisib, a potent, selective PI3Kδ inhibitor, was evaluated in patients with APDS1 and APDS2. In the phase 1b study (European Clinical Trials Database 2015-002900-10) patients with genetic and clinical confirmation of APDS1 or APDS2 received 15-25 mg/d seletalisib for 12 wk. Patients could enter an extension study (European Clinical Trials Database 2015-005541). Primary endpoints were safety and tolerability, with exploratory efficacy and immunology endpoints. Seven patients (median age 15 years; APDS1 n = 3; APDS2 n = 4) received seletalisib; five completed the phase 1b study. For the extension study, four patients entered, one withdrew consent (week 24), three completed ≥84 wk of treatment. In the phase 1b study, patients had improved peripheral lymphadenopathy (n = 2), lung function (n = 1), thrombocyte counts (n = 1), and chronic enteropathy (n = 1). Overall, effects were maintained in the extension. In the phase 1b study, percentages of transitional B cells decreased, naive B cells increased, and senescent CD8 T cells decreased (human cells); effects were generally maintained in the extension. Seletalisib-related adverse events occurred in four of seven patients (phase 1b study: hepatic enzyme increased, dizziness, aphthous ulcer, arthralgia, arthritis, increased appetite, increased weight, restlessness, tendon disorder, and potential drug-induced liver injury) and one of four patients had adverse events in the extension (aphthous ulcer). Serious adverse events occurred in three of seven patients (phase 1b study: hospitalization, colitis, and potential drug-induced liver injury) and one of four patients had adverse events in the extension (stomatitis). Patients with APDS receiving seletalisib had improvements in variable clinical and immunological features, and a favorable risk-benefit profile was maintained for ≤96 wk.

Role of P-glycoprotein in the brain disposition of seletalisib: Evaluation of the potential for drug-drug interactions.

Seletalisib is an orally bioavailable selective inhibitor of phosphoinositide 3-kinase delta (PI3Kδ) in clinical development for the treatment of immune-mediated inflammatory diseases. The present study investigated the role of P-gp in seletalisib disposition, especially brain distribution, and the associated risks of interactions. Seletalisib was found to be actively transported by rodent and human P-gp in vitro (transfected LLC-PK1 cells; Km of ca. 20 µM), with minimal or no affinity for the other tested transporters. A distribution study in knockout rats (single oral dosing at 750 mg kg-1) showed that P-gp restricts the brain disposition of seletalisib while having minimal effect on its intestinal absorption. Restricted brain penetration was also observed in cynomolgus monkeys (single oral dosing at 30 mg kg-1) using brain microdialysis and cerebrospinal fluid sampling (Kp,uu of 0.09 and 0.24, respectively). These findings opened the question of potential pharmacokinetic interaction between seletalisib and P-gp inhibitors. In vitro, CsA inhibited the active transport of seletalisib with an IC50 of 0.13 µM. In rats, co-administration of high doses of CsA (bolus iv followed by continuous infusion) increased the brain distribution of seletalisib (single oral dosing at 5 mg kg-1). The observed data were found aligned with those predicted by in vitro-in vivo extrapolation. Based on the same extrapolation method combined with literature data, only very few P-gp inhibitors (i.e. CsA, quinine, quinidine) were predicted to increase the brain disposition of seletalisib in the clinical setting (maximal 3-fold changes).

Safety, Pharmacokinetics, and Pharmacodynamics of the Autotaxin Inhibitor GLPG1690 in Healthy Subjects: Phase 1 Randomized Trials.

GLPG1690 is a novel autotaxin inhibitor in development for the treatment of idiopathic pulmonary fibrosis (IPF). We report phase 1 studies investigating the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of GLPG1690 in healthy subjects. We performed a first-in-human randomized, double-blind, placebo-controlled trial of single (20, 60, 150, 300, 600, 1000, 1500 mg) and multiple (14 days: 150 mg twice daily; 600 and 1000 mg once daily) ascending oral doses of GLPG1690 (NCT02179502), and a randomized, open-label, crossover relative bioavailability study to compare the PK of tablet and capsule formulations of GLPG1690 600 mg and to assess the effect of food on PK of the tablet formulation (NCT03143712). Forty and 13 subjects were randomized in the first-in-human and relative bioavailability studies, respectively. GLPG1690 was well tolerated, with no dose-limiting toxicity at all single and multiple doses. GLPG1690 was rapidly absorbed and eliminated, with a median tmax and mean t1/2 of approximately 2 and 5 hours, respectively. GLPG1690 exposure increased with increasing dose (mean Cmax , 0.09-19.01 µg/mL; mean AUC0-inf , 0.501-168 µg·h/mL, following single doses of GLPG1690 20-1500 mg). PD response, evidenced by rapid reduction in plasma lysophosphatidic acid (LPA) C18:2 levels, increased with increasing GLPG1690 plasma levels, plateauing at approximately 80% reduction in LPA C18:2 at around 0.6 µg/mL GLPG1690. Tablet and capsule formulations had similar PK profiles, and no clinically significant food effect was observed when comparing tablets taken in fed and fasted states. The safety, tolerability, and PK/PD profiles of GLPG1690 support continued clinical development for IPF.

Lack of placental transfer of certolizumab pegol during pregnancy: results from CRIB, a prospective, postmarketing, pharmacokinetic study.

OBJECTIVES: There is a need for effective and safe treatment during pregnancy in women with chronic inflammatory diseases. This study evaluated placental transfer of certolizumab pegol (CZP), an Fc-free anti-tumour necrosis factor drug, from CZP-treated pregnant women to their infants. METHODS: CRIB was a pharmacokinetic (PK) study of women ≥30 weeks pregnant receiving commercial CZP for a locally approved indication (last dose ≤35 days prior to delivery). Blood samples were collected from mothers, umbilical cords and infants at delivery, and infants again at weeks 4 and 8 post-delivery. CZP plasma concentrations were measured with a highly sensitive and CZP-specific electrochemiluminescence immunoassay (lower limit of quantification 0.032 µg/mL). RESULTS: Sixteen women entered and completed the study. Maternal CZP plasma levels at delivery were within the expected therapeutic range (median [range] 24.4 [5.0-49.4] µg/mL). Of the 16 infants, 2 were excluded from the per-protocol set: 1 due to missing data at birth and 1 due to implausible PK data. Of the remaining 14 infants, 13 had no quantifiable CZP levels at birth (<0.032 µg/mL), and 1 had a minimal CZP level of 0.042 µg/mL (infant/mother plasma ratio 0.0009); no infants had quantifiable CZP levels at weeks 4 and 8. Of 16 umbilical cord samples, 1 was excluded due to missing data; 3/15 had quantifiable CZP levels (maximum 0.048 µg/mL). CONCLUSIONS: There was no to minimal placental transfer of CZP from mothers to infants, suggesting lack of in utero foetal exposure during the third trimester. These results support continuation of CZP treatment during pregnancy, when considered necessary. TRIAL REGISTRATION NUMBER: NCT02019602; Results.

A Dual-Administration Microtracer Technique to Characterize the Absorption, Distribution, Metabolism, and Excretion of [14 C]Seletalisib (UCB5857) in Healthy Subjects.

Phosphoinositide 3 kinases are targets for development of small-molecule inhibitors to disrupt progression of immune-inflammatory diseases. This phase 1 open-label study (Eudract 2014-005353-39) evaluated the safety and relative bioavailability of 2 new seletalisib (UCB5857) formulations (A and B) compared with a reference formulation. Absolute bioavailability (period 1a, n = 6) and disposition and metabolism (period 1b, n = 6) of the reference formulation were evaluated: healthy subjects received 30 mg orally plus ∼20 µg of a 14 C-labeled microtracer (intravenously in 1a, orally in 1b). New formulations were evaluated: subjects from periods 1a and 1b were pooled and randomly distributed to receive a single oral dose (30 mg) of formulation A (n = 6) or B (n = 6) in periods 2 and 3, using a crossover design. Absolute oral bioavailability of seletalisib was 97% (90% confidence interval 87, 107). Unchanged [14 C]seletalisib was the predominant radioactive component in plasma (94.8%). After oral dosing, the radioactive dose was primarily recovered in feces (74.6%, geometric coefficient of variation [GeoCV] 18.1%), mostly as metabolites. Seletalisib demonstrated a 24-hour terminal half-life, volume of distribution of 60.9 L (GeoCV 23.8%), and a total plasma clearance of 1.7 L/h (GeoCV 35.4%). Formulations A and B displayed similar or even higher exposure compared with reference seletalisib (areas under the concentration-time curves 19 337 [GeoCV 30.8%], 20 380 [GeoCV 37.7%], and 15 932 [GeoCV 36.4%] h·ng/mL, respectively). New formulations A and B were bioequivalent with each other, and all 3 formulations showed acceptable safety profiles. This radiolabeled microtracer approach successfully informed on the absorption, distribution, metabolism, and excretion of seletalisib and further guided the mechanistic pharmacokinetic modeling.

First-in-human studies of seletalisib, an orally bioavailable small-molecule PI3Kδ inhibitor for the treatment of immune and inflammatory diseases.

PURPOSE: PI3Ks are potential therapeutic targets in immune-inflammatory diseases. These studies aimed to investigate the safety, tolerability and PK profile of seletalisib, a selective inhibitor of PI3Kδ in humans. METHODS: These phase I, randomised, double-blind, placebo-controlled, single-centre studies (NCT02303509, NCT02207595) evaluated single and multiple oral doses of seletalisib (5-90 mg QD and 30 mg BID) in healthy adults and subjects with mild-to-moderate psoriasis (Study-1). Pharmacodynamic effects on markers of inflammation were assessed via changes in ex vivo basophil degranulation and histological assessment of psoriatic skin biopsies. RESULTS: Seletalisib was well tolerated at doses ≤15 mg (Study-1) and ≤45 mg QD (Study-2) for 14 days. No safety concerns or dose-limiting toxicities were identified (Study-1). Incidence of gastrointestinal-related AEs was not dose related but higher incidences of rash AEs were associated with higher-dose seletalisib (Study-2 rash AEs: 18 in 12 seletalisib-treated subjects versus 1 in 1 placebo-treated subject). Mean seletalisib plasma concentration-time profiles increased with increasing doses after single and multiple dosing, with no major deviations from dose-proportionality. There was no unexpected accumulation or loss of exposure after multiple dosing (time-independent pharmacokinetic profile). Apparent t 1/2 values were supportive of once-daily dosing (geometric mean t1/2: Study-1, 17.7-21.1 h; Study-2, 18.1-22.4 h). No clinically significant food effect was observed (Study-1). Pharmacodynamic findings demonstrated ex vivo inhibition of basophil degranulation, improvements in histological assessment of skin biopsies and other markers of psoriatic biology and preliminary evidence of target engagement in psoriatic skin tissue. CONCLUSIONS: Seletalisib safety, tolerability and pharmacokinetic/pharmacodynamic profiles support its continued clinical development in immune-inflammatory diseases.

First-in-human randomized study of bimekizumab, a humanized monoclonal antibody and selective dual inhibitor of IL-17A and IL-17F, in mild psoriasis.

AIMS: To assess safety, pharmacokinetics (PK) and clinical efficacy of bimekizumab (formerly UCB4940), a novel humanized monoclonal antibody and dual inhibitor of interleukin (IL)-17A and IL-17F, in subjects with mild plaque psoriasis. METHODS: Randomized, double-blind, first-in-human study of bimekizumab in 39 subjects who received single-dose intravenous bimekizumab (8-640 mg) or placebo (NCT02529956). RESULTS: Bimekizumab demonstrated dose-proportional linear PK and was tolerated across the dose range assessed. No subject discontinued due to treatment-emergent adverse events and no severe adverse events were reported. Bimekizumab demonstrated fast onset of clinically-meaningful effects on skin of patients with mild psoriasis as early as Week 2. Maximal improvements (100% or near 100% reductions from baseline) in all measures of disease activity were observed between Weeks 8-12 in subjects receiving 160-640 mg bimekizumab. The duration of effect at doses ≥160 mg was evident up to Weeks 12-20 after a single intravenous dose, dependent on endpoint. CONCLUSIONS: This is the first study to demonstrate the safety, tolerability and clinical efficacy of a dual IL-17A and IL-17F inhibitor, in subjects with mild psoriasis. Bimekizumab showed fast onset of clinically-meaningful efficacy by Week 2, with a maximal or near-maximal magnitude of response that was maintained up to study Weeks 12-20. These findings support the continued clinical development of bimekizumab for diseases mediated by both IL-17A and IL-17F, including psoriasis.