Factors contributing to the nonlinear pharmacokinetics of astegolimab: a close examination of potential causes.

Aim: This paper describes a case study of an antibody therapeutic targeting a membrane-bound receptor, also present in systemic circulation, as a soluble receptor. During phase I studies of astegolimab, nonlinear pharmacokinetics (PKs) were observed. We investigated the potential contribution of antidrug antibodies, target-mediated drug disposition and assay format. Materials & methods: A more target-tolerant assay was developed, and a subset of phase I samples were evaluated in both free and total PK assay formats. Results & conclusion: Our results demonstrate that there were two main contributors to PK nonlinearity: soluble target interference in the free PK assay, in addition to target-mediated drug disposition. Antidrug antibody status did not significantly impact PK.

Population Pharmacokinetics of Heptanoate in Healthy Subjects and Patients With Long-Chain Fatty Acid Oxidation Disorders Treated With Triheptanoin.

Triheptanoin is an odd-carbon, medium-chain triglyceride consisting of three fatty acids with seven carbons each on a glycerol backbone, indicated for the treatment of adult and pediatric patients with long-chain fatty acid oxidation disorders (LC-FAOD). A total of 562 plasma concentrations of heptanoate, the most abundant and pharmacologically active metabolite of triheptanoin, from 13 healthy adult subjects and 30 adult and pediatric subjects with LC-FAOD were included in the population pharmacokinetic (PK) analyses. Multiple peaks of heptanoate observed in several subjects were characterized by dual first-order absorption with a lag time in the second absorption compartment. The disposition of heptanoate in human plasma was adequately described by one-compartmental distribution with a linear elimination. The apparent clearance (CL/F) and apparent volume of distribution were allometrically scaled with body weight to describe PK data across a wide range of age groups in subjects with LC-FAOD. The typical CL/F in adult subjects with LC-FAOD was ≈19% lower than that in healthy subjects. Model-estimated elimination half-life for LC-FAOD patients was ∼1.7 hours, supporting a recommended dosing frequency of ≥4 times per day. Covariate analyses indicate that age, race, and sex did not lead to clinically meaningful changes in the exposure of heptanoate.

Efficacy, safety, and tolerability of lebrikizumab in adolescent patients with uncontrolled asthma (ACOUSTICS).

Background: Lebrikizumab is a monoclonal antibody that modulates activity of interleukin-13. The Phase 3 ACOUSTICS study assessed lebrikizumab efficacy and safety in adolescents with uncontrolled asthma despite standard-of-care treatment. Methods: Adolescents (aged 12-17 years) with uncontrolled asthma, prebronchodilator forced expiratory volume in 1 s 40%-90% predicted, and stable background therapy were randomised 1:1:1 to receive lebrikizumab 125 or 37.5 mg or placebo subcutaneously once every 4 weeks. Primary efficacy endpoint was asthma exacerbation rate over 52 weeks. Results: Between August 2013 and July 2016, 579 patients were screened and 346 were randomised; 224 (65%) completed the study with 52 weeks of treatment. Lebrikizumab 125 mg (n = 116) reduced the exacerbation rate at 52 weeks versus placebo (n = 117; adjusted rate ratio [RR] 0.49 [95% CI 0.28-0.83]; 51% rate reduction). Lebrikizumab 37.5 mg (n = 113) was less effective at reducing exacerbations (RR 0.60 [95% CI 0.35-1.03]; 40% rate reduction). In patients with blood eosinophil counts ≥300 cells/µl, both lebrikizumab doses reduced exacerbations (125 mg: RR 0.44 [95% CI 0.21-0.89]; 37.5 mg: 0.42 [95% CI 0.19-0.93]). Treatment-emergent adverse events, serious adverse events, and adverse events leading to study discontinuation occurred in 155 (68%), 7 (3%), and 5 (2%) of 229 patients who received lebrikizumab (both 125 and 37.5 mg doses) and in 72 (62%), 4 (3%), and 1 (1%) of 117 who received placebo, respectively. No deaths occurred. Conclusion: Lebrikizumab 125 mg reduced asthma exacerbation rates in adolescents with uncontrolled asthma. However, the study was prematurely terminated (sponsor's decision) potentially limiting interpretation of results. Clinical trial registration: NCT01875003 (www.ClinicalTrials.gov).

Population Pharmacokinetics and Exposure-Response Relationships of Astegolimab in Patients With Severe Asthma.

Astegolimab is a fully human immunoglobulin G2 monoclonal antibody that binds to the ST2 receptor and blocks the interleukin-33 signaling. It was evaluated in patients with uncontrolled severe asthma in the phase 2b study (Zenyatta) at doses of 70, 210, and 490 mg subcutaneously every 4 weeks for 52 weeks. This work aimed to characterize astegolimab pharmacokinetics, identify influential covariates contributing to its interindividual variability, and make a descriptive assessment of the exposure-response relationships. A population pharmacokinetic model was developed using data from 368 patients in the Zenyatta study. Predicted average steady-state concentration was used in the subsequent exposure-response analyses, which evaluated efficacy (asthma exacerbation rate) and biomarker end points including forced expiratory volume in 1 second, fraction exhaled nitric oxide, blood eosinophils, and soluble ST2. A 2-compartment disposition model with first-order elimination and first-order absorption best described the astegolimab pharmacokinetics. The relative bioavailability for the 70-mg dose was 15.3% lower. Baseline body weight, estimated glomerular filtration rate, and eosinophils were statistically correlated with pharmacokinetic parameters, but only body weight had a clinically meaningful influence on the steady-state exposure (ratios exceeding 0.8-1.25). The exposure-response of efficacy and biomarkers were generally flat with a weak trend in favor of the highest dose/exposure. This study characterized astegolimab pharmacokinetics in patients with asthma and showed typical pharmacokinetic behavior as a monoclonal antibody-based drug. The exposure-response analyses suggested the highest dose tested in the Zenyatta study (490 mg every 4 weeks) performed close to the maximum effect, and no additional response may be expected above it.

Pharmacokinetics and exposure-efficacy relationships of omalizumab in patients with nasal polyps.

The anti-immunoglobulin E (IgE) antibody, omalizumab (Xolair), is approved in the United States for the treatment of allergic asthma and chronic spontaneous urticaria, and has recently been studied for the treatment of nasal polyposis following completion of the two replicate phase 3 studies (POLYP 1 and POLYP 2). The dosing of omalizumab used in the phase 3 studies is based on a combination of patients' pre-treatment IgE level and body weight, similar to the approach used in allergic asthma. The objectives of the current analyses were to evaluate whether the pharmacokinetics (PK) of omalizumab and its pharmacodynamic (PD) effect on free and total IgE level in chronic rhinosinusitis with nasal polyps (CRSwNP) are consistent with those in allergic asthma via population PK/PD modeling and simulation, and to graphically explore exposure-response relationships and free IgE-response relationships in CRSwNP. Omalizumab PK and PD effect of total and free IgE in CRSwNP are generally consistent with those in asthma. Observed post-treatment free IgE suppressions were generally within the target range of the baseline IgE- and body weight-based omalizumab dosing table, with 74.2% and 93.0% of patients achieving a serum free IgE level below 25 ng/mL and 50 ng/mL, respectively at Week 24. Exposure-response analyses indicated that there was no clear correlation between omalizumab or free IgE concentration and key efficacy endpoints within the POLYP studies. Overall, these results indicate that the body weight and IgE-based dosing regimen of omalizumab was appropriate for use in CRSwNP patients.

Population repeated time-to-event analysis of exacerbations in asthma patients: A novel approach for predicting asthma exacerbations based on biomarkers, spirometry, and diaries/questionnaires.

Identification of covariates, including biomarkers, spirometry, and diaries/questionnaires, that predict asthma exacerbations would allow better clinical predictions, shorter phase II trials and inform decisions on phase III design, and/or initiation (go/no-go). The objective of this work was to characterize asthma-exacerbation hazard as a function of baseline and time-varying covariates. A repeated time-to-event (RTTE) model for exacerbations was developed using data from a 52-week phase IIb trial, including 502 patients with asthma randomized to placebo or 70 mg, 210 mg, or 490 mg astegolimab every 4 weeks. Covariate analysis was performed for 20 baseline covariates using the full random effects modeling approach, followed by time-varying covariate analysis of nine covariates using the stepwise covariate model (SCM) building procedure. Following the SCM, an astegolimab treatment effect was explored. Diary-based symptom score (difference in objective function value [dOFV] of -83.7) and rescue medication use (dOFV = -33.5), and forced expiratory volume in 1 s (dOFV = -14.9) were identified as significant time-varying covariates. Of note, time-varying covariates become more useful with more frequent measurements, which should favor the daily diary scores over others. The most influential baseline covariates were exacerbation history and diary-based symptom score (i.e., symptom score was important as both time-varying and baseline covariate). A (nonsignificant) astegolimab treatment effect was included in the final model because the limited data set did not allow concluding the remaining effect size as irrelevant. Without time-varying covariates, the treatment effect was statistically significant (p < 0.01). This work demonstrated the utility of a population RTTE approach to characterize exacerbation hazard in patients with severe asthma.

Translational and pharmacokinetic-pharmacodynamic application for the clinical development of GDC-0334, a novel TRPA1 inhibitor.

GDC-0334 is a novel small molecule inhibitor of transient receptor potential cation channel member A1 (TRPA1), a promising therapeutic target for many nervous system and respiratory diseases. The pharmacokinetic (PK) profile and pharmacodynamic (PD) effects of GDC-0334 were evaluated in this first-in-human (FIH) study. A starting single dose of 25 mg was selected based on integrated preclinical PK, PD, and toxicology data following oral administration of GDC-0334 in guinea pigs, rats, dogs, and monkeys. Human PK and PK-PD of GDC-0334 were characterized after single and multiple oral dosing using a population modeling approach. The ability of GDC-0334 to inhibit dermal blood flow (DBF) induced by topical administration of allyl isothiocyanate (AITC) was evaluated as a target-engagement biomarker. Quantitative models were developed iteratively to refine the parameter estimates of the dose-concentration-effect relationships through stepwise estimation and extrapolation. Human PK analyses revealed that bioavailability, absorption rate constant, and lag time increase when GDC-0334 was administered with food. The inhibitory effect of GDC-0334 on the AITC-induced DBF biomarker exhibited a clear sigmoid-Emax relationship with GDC-0334 plasma concentrations in humans. This study leveraged emerging preclinical and clinical data to enable iterative refinement of GDC-0334 mathematical models throughout the FIH study for dose selection in subsequent cohorts throughout the study. Study Highlights WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? GDC-0334 is a novel, small molecule TRPA1 inhibitor and a pharmacokinetic-pharmacodynamic (PK-PD) modeling strategy could be implemented in a systematic and step-wise manner to build and learn from emerging data for early clinical development. WHAT QUESTION DID THIS STUDY ADDRESS? Can noncompartmental and population-based analyses be used to describe the PK and PD characteristics of GDC-0334 in preclinical and clinical studies? WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? GDC-0334 exposure generally increased with dose in rats, dogs, and monkeys. The starting dose (25 mg) in the clinical study was determined based on the preclinical data. GDC-0334 exhibited linear PK in humans and the bioavailability was increased with food. The inhibitory effect of GDC-0334 on dermal blood flow induced by the TRPA1 agonist allyl isothiocyanate in humans indicates a clear PK-PD relationship. HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE? The models developed based on TRPA1 agonist-induced dermal blood flow inhibition data can be used to predict PK-PD relationships in future preclinical and clinical studies evaluating new drug entities that target TRPA1.

A randomized, placebo-controlled trial evaluating effects of lebrikizumab on airway eosinophilic inflammation and remodelling in uncontrolled asthma (CLAVIER).

BACKGROUND: The anti-interleukin 13 (IL-13) monoclonal antibody lebrikizumab improves lung function in patients with moderate-to-severe uncontrolled asthma, but its effects on airway inflammation and remodelling are unknown. CLAVIER was designed to assess lebrikizumab's effect on eosinophilic inflammation and remodelling. OBJECTIVE: To report safety and efficacy results from enrolled participants with available data from CLAVIER. METHODS: We performed bronchoscopy on patients with uncontrolled asthma before and after 12 weeks of randomized double-blinded treatment with lebrikizumab (n = 31) or placebo (n = 33). The pre-specified primary end-point was relative change in airway subepithelial eosinophils per mm2 of basement membrane (cells/mm2 ). Pre-specified secondary and exploratory outcomes included change in IL-13-associated biomarkers and measures of airway remodelling. RESULTS: There was a baseline imbalance in tissue eosinophils and high variability between treatment groups. There was no discernible change in adjusted mean subepithelial eosinophils/mm2 in response to lebrikizumab (95% CI, -82.5%, 97.5%). As previously observed, FEV1 increased after lebrikizumab treatment. Moreover, subepithelial collagen thickness decreased 21.5% after lebrikizumab treatment (95% CI, -32.9%, -10.2%), and fractional exhaled nitric oxide, CCL26 and SERPINB2 mRNA expression in bronchial tissues also reduced. Lebrikizumab was well tolerated, with a safety profile consistent with other lebrikizumab asthma studies. CONCLUSIONS & CLINICAL RELEVANCE: We did not observe reduced tissue eosinophil numbers in association with lebrikizumab treatment. However, in pre-specified exploratory analyses, lebrikizumab treatment was associated with reduced degree of subepithelial fibrosis, a feature of airway remodelling, as well as improved lung function and reduced key pharmacodynamic biomarkers in bronchial tissues. These results reinforce the importance of IL-13 in airway pathobiology and suggest that neutralization of IL-13 may reduce asthmatic airway remodelling. CLINICAL TRIAL REGISTRATION: NCT02099656.

Comparability Considerations and Challenges for Expedited Development Programs for Biological Products.

Expedited development programs for biological products to be used in the treatment of serious conditions bring about challenges because of the compressed clinical development timeframes. As expedited development does not lessen the quality expectations, one challenge is providing adequate chemistry, manufacturing, and control (CMC) information required to support approval of a biological product. In particular, the analytical comparability and, in some cases, pharmacokinetic comparability studies needed to bridge the clinical material to the commercial material could delay submission of applications for life-saving medicines. While there is the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Topic Q5E guidance on assessing comparability of biological products before and after manufacturing changes, specific guidance on the emerging issue of conducting comparability exercises in the face of expedited drug development is lacking. In July 2019, clinical pharmacologists and product quality chemists from the US FDA and industry representatives convened an FDA workshop for a scientific exchange about considerations and challenges around conducting comparability exercises for expedited programs for biological products. This article highlights discussions from the workshop.

Efficacy and safety of lebrikizumab in adult patients with mild-to-moderate asthma not receiving inhaled corticosteroids.

BACKGROUND: Asthma is a heterogeneous and complex disease in both its clinical course and response to treatment. IL-13 is central to Type 2 inflammation and contributes to many features of asthma. In a previous Phase 2 study, lebrikizumab, an anti-IL-13 monoclonal antibody, did not significantly improve FEV1 in mild-to-moderate asthma patients not receiving ICS therapy. This Phase 3 study was designed to further assess the efficacy and safety of lebrikizumab in adult patients with mild-to-moderate asthma treated with daily short-acting ß2-agonist therapy alone. METHODS: Adult patients with mild-to-moderate asthma were randomised to receive lebrikizumab 125 mg subcutaneously (SC), placebo SC, or montelukast 10 mg orally for 12 weeks, with an 8-week follow-up period. The primary efficacy endpoint was absolute change in pre-bronchodilator FEV1 from baseline at Week 12. FINDINGS: A total of 310 patients were randomised and dosed in the study. The mean absolute change in FEV1 from baseline at Week 12 was higher in the lebrikizumab-treated arm compared with placebo (150 mL versus 67 mL); however, this improvement did not achieve statistical significance (overall adjusted difference of 83 mL [95% CI: -3, 170]; p = .06). Montelukast did not improve FEV1 as compared with placebo. Lebrikizumab was generally safe and well tolerated during the study. INTERPRETATION: Lebrikizumab did not significantly improve FEV1 in mild-to-moderate asthma patients at a dose expected to inhibit the IL-13 pathway. Inhibiting IL-13 in this patient population was not sufficient to improve lung function. These data support the findings of a previous trial of lebrikizumab in patients not receiving ICS. CLINICAL TRIALS REGISTRY NUMBER: This trial was registered under NCT02104674 at http://www.clinicaltrials.gov.

Efficacy and safety of lebrikizumab (an anti-IL-13 monoclonal antibody) in adults with moderate-to-severe atopic dermatitis inadequately controlled by topical corticosteroids: A randomized, placebo-controlled phase II trial (TREBLE).

BACKGROUND: Interleukin (IL)-13 plays a key role in type 2 inflammation and is an emerging pathogenic mediator in atopic dermatitis (AD). OBJECTIVE: We investigated the efficacy and safety of lebrikizumab, an IL-13 monoclonal antibody, as an add-on to topical corticosteroid (TCS) treatment. METHODS: A randomized, placebo-controlled, double-blind, phase 2 study. Adults with moderate-to-severe AD were required to use TCS twice daily and then randomized (1:1:1:1) to lebrikizumab 125 mg single dose, lebrikizumab 250 mg single dose, lebrikizumab 125 mg every 4 weeks for 12 weeks, or placebo every 4 weeks for 12 weeks, after a 2-week TCS run-in. The primary endpoint was percentage of patients achieving Eczema Area and Severity Index (EASI)-50 at week 12. RESULTS: In total, 209 patients received the study drug. At week 12, significantly more patients achieved EASI-50 with lebrikizumab 125 mg every 4 weeks (82.4%; P = .026) than placebo every 4 weeks (62.3%); patients receiving a single dose of lebrikizumab showed no statistically significant improvements in EASI-50 compared with placebo. Adverse events were similar between groups (66.7% all lebrikizumab vs 66.0% placebo) and mostly mild or moderate. LIMITATIONS: Protocol-mandated twice daily TCS treatment limits our understanding of the efficacy of lebrikizumab as a monotherapy. The short study duration did not enable long-term efficacy or safety evaluations. CONCLUSION: When combined with TCS, lebrikizumab 125 mg taken every 4 weeks led to a significant improvement and was well tolerated in patients with moderate-to-severe AD.

Model-based clinical pharmacology profiling and exposure-response relationships of the efficacy and biomarker of lebrikizumab in patients with moderate-to-severe asthma.

Lebrikizumab is a humanized monoclonal antibody that binds to interleukin-13 and has been evaluated as a treatment for moderate-to-severe asthma. Objectives of this work were to characterize lebrikizumab pharmacokinetics (PK), identify influential covariates, and graphically explore exposure-response relationships in moderate-to-severe asthmatics. Pooled PK data from 11 studies were used in the population PK model development. Full covariate modeling was used to evaluate the impact of pre-specified covariates. Response data (exacerbation rate, forced expiratory volume in 1 s [FEV1], and fractional exhaled nitric oxide [FeNO]) were obtained from moderate-to-severe asthmatics (n = 2148) who received placebo, lebrikizumab 37.5 mg or 125 mg every 4 weeks (Q4W) in two replicate phase 3 studies. Graphical exposure-response analyses were stratified by numerous covariates, including biomarker subgroups defined by serum periostin level and blood eosinophil count at baseline. Lebrikizumab PK was described by a two-compartment model with first-order absorption. Population typical values were estimated as 0.156 L/day for clearance (CL), 4.10 L for central volume (Vc), and 0.239 day-1 for absorption rate (ka), 85.6% for bioavailability (inter-subject variability: CL, 33.3%; Vc, 36.3%; ka, 40.8%). The estimated mean terminal half-life was 25.7 days. Body weight was the most influential covariate. Generally, the exposure-response analyses of FEV1 and FeNO showed increased response at higher exposure quartiles, while flat or unclear exposure-response relationships were observed in exacerbation rate. Lebrikizumab PK is as expected for a typical immunoglobulin G4 monoclonal antibody. Results from the exposure-response analyses suggested that, compared to 125 mg Q4W, the 37.5 mg Q4W dose did not achieve the maximum responses for FEV1 and FeNO, although it appeared to maximize the effect on exacerbation reduction. This suggests that the antibody levels needed to improve these outcomes may not be the same. In addition, the role of IL-13 in airflow obstruction/airway inflammation and asthma exacerbations might be different and targeting multiple pathways may be required to treat this heterogeneous disease and provide clinically meaningful benefits to asthma patients.

A Pharmacokinetic Bioequivalence Study Comparing Pirfenidone Tablet and Capsule Dosage Forms in Healthy Adult Volunteers.

INTRODUCTION: Pirfenidone film-coated tablets were developed to offer an alternative to the marketed capsule formulation. This study assessed the bioequivalence of the tablet and capsule formulations under fed and fasted states. METHODS: A Phase I, open-label, randomized, four-treatment-period, four-sequence, crossover pharmacokinetics study (NCT02525484) was conducted. Each subject received an 801-mg single dose of pirfenidone as three 267-mg capsules or one 801-mg tablet under fasted and fed conditions. Pirfenidone plasma C max, AUC0-t and AUC0-∞ were used to assess bioequivalence. RESULTS: Forty-four subjects were randomized to treatment. The 801-mg tablet in the fasted state met bioequivalence criteria [90% confidence intervals (CI) 80.00-125.00%] for the GLSM ratios of natural log-transformed C max, AUC0-t and AUC0-∞. Under fed conditions, the 801-mg tablet met the bioequivalence criteria for AUC0-t and AUC0-∞, but slightly exceeded the bioequivalence criteria for the C max (90% CI of 108.26-125.60%). The tablet C max was approximately 17% higher than that of the capsules. In the fed state, the tablet C max, and both AUC0-t and AUC0-∞ were reduced by 39% and 17%, respectively, relative to the fasted state. The tablet and capsules had acceptable tolerability profiles. CONCLUSIONS: The pirfenidone 801-mg tablet met bioequivalence criteria when compared with three 267-mg capsules in the fasted state. The tablet C max was slightly higher relative to capsules in the fed state, but this is not expected to have a clinically meaningful impact on the benefit-risk profile of pirfenidone. FUNDING: This work was supported by F. Hoffmann-La Roche Ltd.

Efficacy and safety of lebrikizumab in patients with uncontrolled asthma (LAVOLTA I and LAVOLTA II): replicate, phase 3, randomised, double-blind, placebo-controlled trials.

BACKGROUND: In phase 2 trials, lebrikizumab, an anti-interleukin-13 monoclonal antibody, reduced exacerbation rates and improved FEV1 in patients with uncontrolled asthma, particularly in those with high concentrations of type 2 biomarkers (eg, periostin or blood eosinophils). We undertook replicate phase 3 studies to assess the efficacy and safety of lebrikizumab in patients with uncontrolled asthma despite inhaled corticosteroids and at least one second controller medication. METHODS: Adult patients with uncontrolled asthma, pre-bronchodilator FEV1 40-80% predicted, and stable background therapy were randomly assigned (1:1:1) with an interactive voice-web-based response system to receive lebrikizumab 37·5 mg or 125 mg, or placebo subcutaneously, once every 4 weeks. Randomisation was stratified by screening serum periostin concentration, history of asthma exacerbations within the last 12 months, baseline asthma medications, and country. The primary efficacy endpoint was the rate of asthma exacerbations over 52 weeks in biomarker-high patients (periostin ≥50 ng/mL or blood eosinophils ≥300 cells per µL), analysed with a Poisson regression model corrected for overdispersion with Pearson χ2 that included terms for treatment group, number of asthma exacerbations within the 12 months before study entry, baseline asthma medications, geographic region, screening periostin concentration, and blood eosinophil counts as covariates. Both trials are registered at ClinicalTrials.gov, LAVOLTA I, number NCT01867125, and LAVOLTA II, number NCT01868061. FINDINGS: 1081 patients were treated in LAVOLTA I and 1067 patients in LAVOLTA II. Over 52 weeks, lebrikizumab reduced exacerbation rates in biomarker-high patients in the 37·5 mg dose group (rate ratio [RR] 0·49 [95% CI 0·34-0·69], p<0·0001) and in the 125 mg dose group (RR 0·70 [0·51-0·95], p=0·0232) versus placebo in LAVOLTA I. Exacerbation rates were also reduced in biomarker-high patients in both dose groups versus placebo in LAVOLTA II (37·5 mg: RR 0·74 [95% CI 0·54-1·01], p=0·0609; 125 mg: RR 0·74 [0·54-1·02], p=0·0626). Pooling both studies, the proportion of patients who experienced treatment-emergent adverse events (79% [1125 of 1432 patients] for both lebrikizumab doses vs 80% [576 of 716 patients] for placebo), serious adverse events (8% [115 patients] for both lebrikizumab doses vs 9% [65 patients] for placebo), and adverse events leading to study drug discontinuation (3% [49 patients] for both lebrikizumab doses vs 4% [31 patients] for placebo) were similar between lebrikizumab and placebo. The following serious adverse events were reported in the placebo-controlled period: one event of aplastic anaemia and five serious adverse events related to raised concentrations of eosinophils in patients treated with lebrikizumab and one event of eosinophilic pneumonia in the placebo group. INTERPRETATION: Lebrikizumab did not consistently show significant reduction in asthma exacerbations in biomarker-high patients. However, it blocked interleukin-13 as evidenced by the effect on interleukin-13-related pharmacodynamic biomarkers, and clinically relevant changes could not be ruled out. FUNDING: F Hoffmann-La Roche.

Lebrikizumab in moderate-to-severe asthma: pooled data from two randomised placebo-controlled studies.

INTRODUCTION: In a subset of patients with asthma, standard-of-care treatment does not achieve disease control, highlighting the need for novel therapeutic approaches. Lebrikizumab is a humanised, monoclonal antibody that binds to and blocks interleukin-13 activity. METHODS: LUTE and VERSE were replicate, randomised, double-blind, placebo-controlled studies, evaluating multiple doses of lebrikizumab in patients with uncontrolled asthma despite the use of medium-to-high-dose inhaled corticosteroid and a second controller. Patients received lebrikizumab 37.5, 125, 250 mg or placebo subcutaneously every four weeks. The primary endpoint was the rate of asthma exacerbations during the placebo-controlled period. Analyses were performed on prespecified subgroups based on baseline serum periostin levels. Following the discovery of a host-cell impurity in the study drug material, protocols were amended to convert from phase III to phase IIb. Subsequently, dosing of study medication was discontinued early as a precautionary measure. The data collected for analysis were from a placebo-controlled period of variable duration and pooled across both studies. RESULTS: The median duration of treatment was approximately 24 weeks. Treatment with lebrikizumab reduced the rate of asthma exacerbations, which was more pronounced in the periostin-high patients (all doses: 60% reduction) than in the periostin-low patients (all doses: 5% reduction); no dose-response was evident. Lung function also improved following lebrikizumab treatment, with greatest increase in FEV1 in periostin-high patients (all doses: 9.1% placebo-adjusted improvement) compared with periostin-low patients (all doses: 2.6% placebo-adjusted improvement). Lebrikizumab was well tolerated and no clinically important safety signals were observed. CONCLUSIONS: These data are consistent with, and extend, previously published results demonstrating the efficacy of lebrikizumab in improving rate of asthma exacerbations and lung function in patients with moderate-to-severe asthma who remain uncontrolled despite current standard-of-care treatment. TRIAL REGISTRATION NUMBERS: The LUTE study was registered under NCT01545440 and the VERSE study under NCT01545453 at http://www.clinicaltrials.gov.

Targeting membrane-expressed IgE B cell receptor with an antibody to the M1 prime epitope reduces IgE production.

Elevated serum levels of both total and allergen-specific immunoglobulin E (IgE) correlate with atopic diseases such as allergic rhinitis and allergic asthma. Neutralization of IgE by anti-IgE antibodies can effectively treat allergic asthma. Preclinical studies indicate that targeting membrane IgE-positive cells with antibodies against M1 prime can inhibit the production of new IgE and significantly reduce the levels of serum IgE. We report results from two trials that investigated the safety, pharmacokinetics, and activity of quilizumab, a humanized monoclonal antibody targeting specifically the M1 prime epitope of membrane IgE, in subjects with allergic rhinitis (NCT01160861) or mild allergic asthma (NCT01196039). In both studies, quilizumab treatment was well tolerated and led to reductions in total and allergen-specific serum IgE that lasted for at least 6 months after the cessation of dosing. In subjects with allergic asthma who were subjected to an allergen challenge, quilizumab treatment blocked the generation of new IgE, reduced allergen-induced early and late asthmatic airway responses by 26 and 36%, respectively, and reduced allergen-induced increases in sputum eosinophils by ~50% compared with placebo. These studies indicate that targeting of membrane IgE-expressing cells with anti-M1 prime antibodies can prevent IgE production in humans.

Dose-ranging study of lebrikizumab in asthmatic patients not receiving inhaled steroids.

BACKGROUND: Asthma is a disease with marked heterogeneity in its clinical course and response to treatment. IL-13 is central to type 2 inflammation, which contributes to many key features of asthma. Lebrikizumab is an anti-IL-13 mAb previously reported to significantly improve lung function in patients with inadequately controlled asthma despite inhaled corticosteroid therapy, especially in periostin-high patients. OBJECTIVE: This phase II study investigated the efficacy and safety of IL-13 blockade with different doses of lebrikizumab in asthmatic patients not receiving inhaled corticosteroids. METHODS: Patients were randomized to receive 125, 250, or 500 mg of lebrikizumab or placebo subcutaneously monthly for 12 weeks with an 8-week follow-up period. The primary efficacy end point was the relative change in prebronchodilator FEV1 from baseline to week 12. RESULTS: A total of 212 patients were randomized. The mean relative change in FEV1 was numerically higher in all lebrikizumab dose groups versus the placebo group, although the difference was neither statistically nor clinically significant. There were no meaningful differences in changes in FEV1 between the dose groups and the placebo group by the periostin subgroup. Lebrikizumab treatment was associated with a reduced risk of treatment failure at all doses versus placebo (P < .001), and results were similar by the periostin subgroup, with no apparent differences between doses of lebrikizumab. Lebrikizumab was generally well tolerated. CONCLUSION: Blocking IL-13, a single cytokine, in this population of asthmatic patients is insufficient to improve lung function. There is evidence that IL-13 blockade may improve disease control, as measured by prevention of protocol-defined treatment failure in these patients.

Population-based efficacy modeling of omalizumab in patients with severe allergic asthma inadequately controlled with standard therapy.

Omalizumab, a recombinant humanized monoclonal antibody, is the first approved anti-immunoglobulin E (IgE) agent for the treatment of subjects with moderate to severe persistent allergic asthma that are inadequately controlled by the standard of care. The objective of this study was to quantitatively characterize relationships between serum free IgE and pulmonary function (as measured by forced expiratory volume in 1 s [FEV1]) as well as serum free IgE and airway inflammation (as measured by fractional exhaled nitric oxide [FeNO]) using population-based efficacy models. Data were collected from patients in the EXTRA trial who received omalizumab or placebo 150 to 375 mg subcutaneously every 2 or 4 weeks from week 0 to 48 with constant standard of care as background therapy. None of the covariates evaluated, including demographics, disease status, and baseline pharmacodynamic biomarkers, were significant in explaining the variability in the FEV1 or FeNO response to omalizumab. Results from the efficacy models further confirmed the current omalizumab dosing rationale based on the mean target free IgE level of 25 ng/ml and quantified the variability for the target. In addition, the resulting population models could be used to predict population FEV1 or FeNO response for omalizumab and/or other anti-IgE therapeutics for which PK-IgE models are constructed.

Minipig as a potential translatable model for monoclonal antibody pharmacokinetics after intravenous and subcutaneous administration.

Subcutaneous (SC) delivery is a common route of administration for therapeutic monoclonal antibodies (mAbs) with pharmacokinetic (PK)/pharmacodynamic (PD) properties requiring long-term or frequent drug administration. An ideal in vivo preclinical model for predicting human PK following SC administration may be one in which the skin and overall physiological characteristics are similar to that of humans. In this study, the PK properties of a series of therapeutic mAbs following intravenous (IV) and SC administration in Göttingen minipigs were compared with data obtained previously from humans. The present studies demonstrated: (1) minipig is predictive of human linear clearance; (2) the SC bioavailabilities in minipigs are weakly correlated with those in human; (3) minipig mAb SC absorption rates are generally higher than those in human and (4) the SC bioavailability appears to correlate with systemic clearance in minipigs. Given the important role of the neonatal Fc-receptor (FcRn) in the PK of mAbs, the in vitro binding affinities of these IgGs against porcine, human and cynomolgus monkey FcRn were tested. The result showed comparable FcRn binding affinities across species. Further, mAbs with higher isoelectric point tended to have faster systemic clearance and lower SC bioavailability in both minipig and human. Taken together, these data lend increased support for the use of the minipig as an alternative predictive model for human IV and SC PK of mAbs.

Effect of antigen binding affinity and effector function on the pharmacokinetics and pharmacodynamics of anti-IgE monoclonal antibodies.

Modulating the binding affinities to IgE or changing the FcγR binding properties of anti-IgE antibodies offers an opportunity to enhance the therapeutic potential of anti-IgE antibodies, but the influence of increased affinity to IgE or reduced Fc effector function on the pharmacological properties of anti-IgE therapies remains unclear. Our studies were designed to characterize the pharmacokinetics, pharmacodynamics and immune-complex distribution of two high-affinity anti-IgE monoclonal antibodies, high-affinity anti-IgE antibody (HAE) 1 and 2, in mice and monkeys. HAE1, also known as PRO98498, is structurally similar to omalizumab (Xolair®), a humanized anti-IgE IgG1 marketed for the treatment of asthma, but differs by 9 amino acid changes in the complementarity-determining region resulting in a 23-fold improvement in affinity. HAE2 is similar to HAE1, but its Fc region was altered to reduce binding to Fcγ receptors. As expected given the decreased binding to Fcγ receptors, systemic exposure to pre-formed HAE2:IgE complexes in mice was greater (six-fold) and distribution to the liver lower (four-fold) compared with HAE1:IgE complexes. In monkeys, systemic exposure to HAE1 was similar to that previously observed for omalizumab in this species, but required comparatively lower serum drug concentrations to suppress free IgE levels. HAE2 treatment resulted in greater exposure and greater increase of total IgE, relative to HAE1, because of decreased clearance of HAE2:IgE complexes. Overall, these data suggest that increased binding affinity to IgE may provide a more effective therapeutic for asthma patients, and that retaining FcγR binding of the anti-IgE antibody is important for elimination of anti-IgE:IgE complexes.