A Phase I Trial of the Dual MET Kinase/OCT-2 Inhibitor OMO-1 in Metastatic Solid Malignancies Including MET Exon 14 Mutated Lung Cancer

INTRODUCTION

Targeted therapy in non-small cell lung cancer (NSCLC) patients with mesenchymal epithelial transition (MET) exon 14 skipping mutations (METex14) and MET amplifications has improved patients' outcomes. The development of more potent MET kinase inhibitors could further benefit these patients. The aim of this trial is to determine the safety and recommended phase 2 dose (RP2D) of OMO-1 (an oral dual MET kinase/OCT-2 inhibitor) and to assess preliminary clinical efficacy in METex14-positive NSCLC and other MET-positive solid tumors.

MATERIALS AND METHODS

This was a first-in-patient, open-label, multicenter study of OMO-1 in patients with locally advanced or metastatic solid malignancies. A standard 3 + 3 dose escalation design was utilized starting at a dose level of 100 mg BID continuously. Preliminary efficacy was investigated in patients with METex14-positive NSCLC, and MET amplified NSCLC and other solid tumors (MET basket).

RESULTS

In the dose-escalation part, 24 patients were included in 5 dose levels ranging from 100 mg twice daily (BID) to 400 mg BID. Most common adverse events (≥ 20%) were nausea, fatigue, vomiting, increased blood creatinine, and headache. The RP2D was determined at 250 mg BID. In the expansion cohorts, 15 patients were included (10 in METex14-positive NSCLC cohort and 5 in MET basket cohort) and received either 200 or 250 mg BID. Eight out of the 10 patients with METex14 positive NSCLC had stable disease as the best response.

CONCLUSION

OMO-1 was tolerated at the dose of 250 mg BID and shows initial signs of MET inhibition and anti-tumor activity in METex14 mutated NSCLC patients.

Filgotinib, a JAK1 Inhibitor, Modulates Disease-Related Biomarkers in Rheumatoid Arthritis: Results from Two Randomized, Controlled Phase 2b Trials

INTRODUCTION

The Janus kinase (JAK) inhibitor therapeutic class has shown significant clinical benefit in the treatment of rheumatoid arthritis (RA). We sought to gain insight into the mode of action and immunological effects of filgotinib, a JAK1 selective inhibitor, in active RA by analyzing secreted and cell-based biomarkers key to RA pathophysiology in two phase 2b trials of filgotinib in active RA.

METHODS

Immune cell subsets and 34 serum biomarkers were analyzed longitudinally over 12 weeks using blood samples collected from patients with active RA receiving filgotinib (100 or 200 mg once daily) or placebo (PBO) in the two phase 2b trials (DARWIN 1, on a background of methotrexate, and DARWIN 2, as monotherapy).

RESULTS

Consistently across both studies, filgotinib treatment decreased multiple immune response biomarkers that have key roles in RA for immune response, and decreased markers that promote matrix degradation, angiogenesis, leukocyte adhesion, and recruitment. Filgotinib did not significantly modulate T and natural killer (NK) lymphoid subsets, but slightly increased B cell numbers after 12 weeks. Multiple correlations were observed for changes in biomarkers with disease activity score 28-CRP. MIP1β showed modest predictivity at baseline for ACR50 response at 12 weeks in the 100 mg filgotinib dose across both studies (AUROC, 0.65 and 0.67, p < 0.05).

CONCLUSIONS

Filgotinib regulates biomarkers from multiple pathways, indicative of direct and indirect network effects on the immune system and the stromal response. These effects were not associated with reductions of major circulating lymphoid populations.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01888874, NCT01894516.

Differentiated pharmacokinetic and pharmacodynamic properties of a highly selective MET kinase inhibitor, OMO-1: Implications for efficacy and safety

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Background: The MET kinase is an established therapeutic target in a range of cancer indications, being a primary oncogenic and therapy resistance driver. Methods: OMO-1 is a highly potent, selective oral inhibitor of MET kinase and Organic Cation Transporter 2 (OCT2) that is currently being explored in a Phase I/II study (NCT03138083). Results: Pre-clinical data for OMO-1 indicates that anti-tumor efficacy against MET driven tumor models does not require 24/7 exposure in the plasma. PK/PD assessments indicate that OMO-1 efficacy is AUC driven. Exposures above a trough concentration of ~600ng/ml for a period of 6-8hr and an AUC of 3000ng.h/ml result in complete target inhibition sufficient to induce regression or stasis of MET driven in-vivo models. Dosing of OMO-1 at 12.5mg/kg BD 4hr apart, or split over 4 doses 2hr apart, with a dosing-free period of 18-20hr was sufficient to obtain the effects preclinically. The ongoing Phase I/II study in patients with solid tumours utilised learnings from the pre-clinical and FIH study (NCT01964872) where ascending single doses and multiple doses were evaluated. The selected starting dose for the patient study (100mg BD, 4 hr apart) achieved exposures above the predicted MBAD. Paired tumor biopsies were obtained from a higher dose level (200mg BD). A MET exon 14 skipping mutation NSCLC patient at this dosed demonstrated near-complete inhibition of phospho MET accompanied by signs of clinical benefit and lesion shrinkage, thereby matching the preclinical data. Certain ‘class effect’ adverse events, such as edema, were not observed. Conclusions: OMO-1 is an oral, potent MET TKI with a novel dosing regime, identified during preclinical optimization (BD 4hr apart), that demonstrates encouraging signs of clinical activity without certain ‘class-specific’ adverse events. Further evaluation of this differentiated and efficacious agent is warranted and ongoing.

Modular phase I/II clinical trial evaluating the selective MET-kinase inhibitor OMO-1 in patients with advanced malignancies: Safety and proof of mechanism

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Background: MET kinase is a therapeutic target in a range of cancer indications; it is a primary oncogenic driver and a mechanism of therapy resistance. OMO-1 is a highly potent, selective oral inhibitor of MET kinase and Organic Cation Transporter 2 (OCT2). Methods: This study assesses the safety, tolerability, pharmacokinetics (PK) and preliminary activity of OMO-1 in patients (pts) with advanced malignancies (NCT03138083). Module 1 data, evaluating ascending doses of OMO-1 monotherapy, are reported here. Results: As of January 16, 2019, 34 pts were enrolled at 5 twice-daily (BD) dose levels of OMO-1: 100, 200, 250, 350, and 400 mg, including 10 with MET gene amplified or mutated tumours. OMO-1 was generally well tolerated between 100 - 250 mg BD; pts were in the study for an average of 94 days (range: 15-291 days) and 20/34 pts discontinued due to disease progression. Most frequently-reported AEs were nausea (17/34), vomiting (14/34) and fatigue (14/34), mainly G1-2. Notably, no peripheral oedema, cardiovascular events or non-malignancy related LFT abnormalities were observed. A total of 36 SAEs were reported: 17 in 11 subjects were considered related to OMO-1, and included nausea (3/17), vomiting (4/17), chills, diarrhoea, influenza-like illness (2/17), increased blood bilirubin, blood creatinine (3/17) and neutrophil count, and sepsis. A dose of 250 mg BD was determined as the recommended Phase 2 dose (RP2D); doses ≥350mg BD were not in keeping with optimum long-term dosing: at 400 mg BD, 2/3 subjects experienced influenza-like illness (G2 and G3) and at 350 mg BD 2/5 subjects had G2 fatigue and nausea/vomiting. OMO-1 has a half-life of 2.5-3 hrs and plasma exposure is dose-proportional without accumulation. Elevated creatinine was observed across all dose levels, consistent with OCT2 inhibition. IHC analysis on paired tumour biopsies from a MET-mutated NSCLC pt dosed at 200 mg BD showed near-complete inhibition of phosphorylated MET, without affecting total MET. Conclusions: OMO-1 has a favourable safety profile at a RP2D of 250mg BD. Expansion cohorts for MET mutated/amplified tumour types are enrolling. Clinical trial information: NCT03138083.

Efficacy and safety of filgotinib, a selective Janus kinase 1 inhibitor, in patients with active psoriatic arthritis (EQUATOR): results from a randomised, placebo-controlled, phase 2 trial

BACKGROUND

The Janus kinase 1 (JAK1) pathway has been implicated in the pathogenesis of psoriatic arthritis. We aimed to investigate the efficacy and safety of filgotinib, a selective JAK1 inhibitor, for the treatment of psoriatic arthritis.

METHODS

The EQUATOR trial was a randomised, double-blind, placebo-controlled phase 2 trial that enrolled adults from 25 sites in seven countries (Belgium, Bulgaria, Czech Republic, Estonia, Poland, Spain, and Ukraine). Patients (aged ≥18 years) had active moderate-to-severe psoriatic arthritis (defined as at least five swollen joints and at least five tender joints) fulfilling Classification for psoriatic arthritis (CASPAR) criteria, active or a documented history of plaque psoriasis, and an insufficient response or intolerance to at least one conventional synthetic disease-modifying anti-rheumatic drug (csDMARD). Patients continued to take csDMARDs during the study if they had received this treatment for at least 12 weeks before screening and were on a stable dose for at least 4 weeks before baseline. Using an interactive web-based system, we randomly allocated patients (1:1) to filgotinib 200 mg or placebo orally once daily for 16 weeks (stratified by current use of csDMARDs and previous use of anti-tumour necrosis factor). Patients, study team, and sponsor were masked to treatment assignment. The primary endpoint was proportion of patients achieving 20% improvement in American College of Rheumatology response criteria (ACR20) at week 16 in the full analysis set (patients who received at least one dose of study drug), which was compared between groups with the Cochran-Mantel-Haenszel test and non-responder imputation method. This trial is registered with ClincalTrials.gov, number NCT03101670.

FINDINGS

Between March 9, and Sept 27, 2017, 191 patients were screened and 131 were randomly allocated to treatment (65 to filgotinib and 66 to placebo). 60 (92%) patients in the filgotinib group and 64 (97%) patients in the placebo group completed the study; five patients (8%) in the filgotinib group and two patients (3%) in the placebo group discontinued treatment. 52 (80%) of 65 patients in the filgotinib group and 22 (33%) of 66 in the placebo group achieved ACR20 at week 16 (treatment difference 47% [95% CI 30·2-59·6], p<0·0001). 37 (57%) patients who received filgotinib and 39 (59%) patients who received placebo had at least one treatment-emergent adverse event. Six participants had an event that was grade 3 or worse. The most common events were nasopharyngitis and headache, occurring at similar proportions in each group. One serious treatment-emergent adverse event was reported in each group (pneumonia and hip fracture after a fall), one of which (pneumonia) was fatal in the filgotinib group.

INTERPRETATION

Filgotinib is efficacious for the treatment of active psoriatic arthritis, and no new safety signals were identified.

FUNDING

Galapagos and Gilead Sciences.

Influence of age and renal impairment on the steady state pharmacokinetics of filgotinib, a selective JAK1 inhibitor

Aims

Filgotinib (GS‐6034, formerly GLPG0634) is an oral, selective Janus kinase 1 (JAK1) inhibitor that showed early response and sustained efficacy in patients with rheumatoid arthritis and with Crohn's disease. The aim of the present study was to investigate the impact of age and renal impairment (RI) on the pharmacokinetics (PK) of filgotinib and its main metabolite.

Methods

The effect of age was assessed in two groups of 10 elderly healthy subjects (65–74 and ≥75 years of age) and a control group of 10 younger healthy subjects (40–50 years of age). The impact of RI was investigated in three groups of subjects with mild (n = 6), moderate (n = 6) and severe (n = 3) RI [estimated glomerular filtration rate (eGFR) 60–89, 30–59 and 15–29 ml min^–1 1.73 m^–2, respectively] and a control group (n = 9) with normal renal function (eGFR ≥90 ml min^–1 1.73 m^–2). The PK of filgotinib and its metabolite were evaluated following filgotinib 100 mg once‐daily doses for 10 days.

Results

At steady state, the exposure [area under the concentration–time curve over the dosing interval (AUC_0–24 h)] of filgotinib and its metabolite was moderately higher (1.45‐ and 1.33‐fold, respectively) in the elderly subjects (≥75 years) compared with younger subjects. Renal clearance for filgotinib and its metabolite decreased with the degree of RI, leading to a maximum increase in AUC_0–24 h of 1.54‐fold for filgotinib and 2.74‐fold for the metabolite in subjects with severe RI. Filgotinib was generally safe and well tolerated.

Conclusions

Age and mild to moderate impairment of renal function had limited impact on the PK of filgotinib. In subjects with severe RI, the exposure to the metabolite of filgotinib was elevated, consistent with its renal elimination pathway.

Effect of filgotinib, a selective JAK 1 inhibitor, with and without methotrexate in patients with rheumatoid arthritis: patient-reported outcomes

Background

The aim was to assess patient-reported outcomes (PROs) in patients with rheumatoid arthritis (RA) treated with filgotinib during two phase 2b, 24-week, randomized, placebo-controlled studies.

Methods

Patients with moderate-to-severe active RA and an inadequate response to methotrexate (MTX) were randomized to daily placebo or filgotinib 50 mg, 100 mg, or 200 mg as add-on therapy to MTX (NCT01888874) or as monotherapy (NCT01894516). At week 12, nonresponders receiving filgotinib 50 mg in both studies or placebo in the add-on study, and all patients receiving placebo as monotherapy, were re-assigned to filgotinib 100 mg. PROs were measured using the Health Assessment Questionnaire - Disability Index (HAQ-DI) including Patient Pain assessed by visual analog scale, and the Patient Global Assessment of Disease Activity (Patient Global), the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue Scale (Version 4), and the 36-Item Short Form Health Survey (SF-36).

Results

At week 12, improvements in all PROs, apart from the SF-36 mental component in the add-on study, were statistically better with filgotinib than placebo; some improvements were noted as early as the first assessment time point (week 1 or week 4). Filgotinib improved HAQ-DI by 0.58–0.84 points, FACIT-Fatigue by 6.9–11.4 points, Patient Global by 25.2–35.6 mm, and Pain by 24.2–37.9 mm; scores were maintained or improved to week 24. Across all PROs, more patients achieved minimal clinically important differences and normative values with filgotinib 200 mg than placebo. Patients re-assigned to filgotinib 100 mg at week 12 experienced improvements in PROs between weeks 12 to 24.

Conclusions

Filgotinib as MTX add-on therapy or as monotherapy demonstrated rapid and sustained (to 24 weeks) improvements in health-related quality of life and functional status in patients with active RA.

Trial registration

MTX add-on study: ClinicalTrials.gov, NCT01888874. Registered on 28 June 2013. Monotherapy study: ClinicalTrials.gov, NCT01894516. Registered on 10 July 2013.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1541-z) contains supplementary material, which is available to authorized users.

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.

Clinical remission in patients with moderate-to-severe Crohn's disease treated with filgotinib (the FITZROY study): results from a phase 2, double-blind, randomised, placebo-controlled trial

BACKGROUND

Filgotinib (GLPG0634, GS-6034) is a once-daily, orally administered, Janus kinase 1 (JAK1)-selective inhibitor. The FITZROY study examined the efficacy and safety of filgotinib for the treatment of moderate-to-severe Crohn's disease.

METHODS

We did a randomised, double-blind, placebo-controlled phase 2 study, which recruited patients from 52 centres in nine European countries. We enrolled eligible patients aged 18-75 years with a documented history of ileal, colonic, or ileocolonic Crohn's disease for 3 months or more before screening, as assessed by colonoscopy and supported by histology, and a Crohn's Disease Activity Index (CDAI) score during screening between 220 and 450 inclusive. Patients were randomly assigned (3:1) to receive filgotinib 200 mg once a day or placebo for 10 weeks. Patients were stratified according to previous anti-tumour necrosis factor alpha exposure, C-reactive protein concentration at screening (≤10 mg/L or >10 mg/L), and oral corticosteroid use at baseline, using an interactive web-based response system. The primary endpoint was clinical remission, defined as CDAI less than 150 at week 10. After week 10, patients were assigned based on responder status to filgotinib 100 mg once a day, filgotinib 200 mg once a day, or placebo for an observational period lasting a further 10 weeks. The filgotinib and placebo treatment groups were compared using ANCOVA models and logistic regression models containing baseline values and randomisation stratification factors as fixed effects. Analyses were done on the intention-to-treat non-responder imputation set. The trial was registered at ClinicalTrials.gov, number NCT02048618.

FINDINGS

Between Feb 3, 2014, and July 10, 2015, we enrolled 174 patients with active Crohn's disease confirmed by centrally read endoscopy (130 in the filgotinib 200 mg group and 44 in the placebo group). In the intention-to-treat population, 60 (47%) of 128 patients treated with filgotinib 200 mg achieved clinical remission at week 10 versus ten (23%) of 44 patients treated with placebo (difference 24 percentage points [95% CI 9-39], p=0·0077). In a pooled analysis of all periods of filgotinib and placebo exposure over 20 weeks, serious treatment-emergent adverse effects were reported in 14 (9%) of 152 patients treated with filgotinib and three (4%) of 67 patients treated with placebo.

INTERPRETATION

Filgotinib induced clinical remission in significantly more patients with active Crohn's disease compared with placebo, and had an acceptable safety profile.

FUNDING

Galapagos.

Clinical Confirmation that the Selective JAK1 Inhibitor Filgotinib (GLPG0634) has a Low Liability for Drug-drug Interactions

OBJECTIVE

The selective Janus kinase 1 inhibitor filgotinib (GLPG0634), which is currently in clinical development for the treatment of rheumatoid arthritis (RA) and Crohn's disease, demonstrated encouraging safety and efficacy profiles in RA patients after 4 weeks of daily dosing. As RA patients might be treated with multiple medications simultaneously, possible drug-drug interactions of filgotinib with cytochrome P450 enzymes and with key drug transporters were evaluated in vitro and in clinical studies.

METHODS

The enzymes involved in filgotinib's metabolism and the potential interactions of the parent and its active major metabolite with drug-metabolizing enzymes and drug transporters, were identified using recombinant enzymes, human microsomes, and cell systems. Furthermore, filgotinib's interaction potential with CYP3A4 was examined in an open-label study in healthy volunteers, which evaluated the impact of filgotinib co-administration on the CYP3A4-sensitive substrate midazolam. The potential interaction with the common RA drug methotrexate was investigated in a clinical study in RA patients.

RESULTS

In vitro, filgotinib and its active metabolite at clinically relevant concentrations did not interact with cytochrome P450 enzymes and uridine 5'-diphospho-glucuronosyltransferases, and did not inhibit key drug transporters. In the clinic, a lack of relevant pharmacokinetic drug interactions by filgotinib and its active metabolite with substrates of CYP3A4, as well as with organic anion transporters involved in methotrexate elimination were found.

CONCLUSION

the collective in vivo and in vitro data on drug-metabolizing enzymes and on key drug transporters, support co-administration of filgotinib with commonly used RA drugs to patients without the need for dose adjustments.

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.

Rational design of a multiepitope vaccine encoding T-lymphocyte epitopes for treatment of chronic hepatitis B virus infections

Protein sequences from multiple hepatitis B virus (HBV) isolates were analyzed for the presence of amino acid motifs characteristic of cytotoxic T-lymphocyte (CTL) and helper T-lymphocyte (HTL) epitopes with the goal of identifying conserved epitopes suitable for use in a therapeutic vaccine. Specifically, sequences bearing HLA-A1, -A2, -A3, -A24, -B7, and -DR supertype binding motifs were identified, synthesized as peptides, and tested for binding to soluble HLA. The immunogenicity of peptides that bound with moderate to high affinity subsequently was assessed using HLA transgenic mice (CTL) and HLA cross-reacting H-2(bxd) (BALB/c x C57BL/6J) mice (HTL). Through this process, 30 CTL and 16 HTL epitopes were selected as a set that would be the most useful for vaccine design, based on epitope conservation among HBV sequences and HLA-based predicted population coverage in diverse ethnic groups. A plasmid DNA-based vaccine encoding the epitopes as a single gene product, with each epitope separated by spacer residues to enhance appropriate epitope processing, was designed. Immunogenicity testing in mice demonstrated the induction of multiple CTL and HTL responses. Furthermore, as a complementary approach, mass spectrometry allowed the identification of correctly processed and major histocompatibility complex-presented epitopes from human cells transfected with the DNA plasmid. A heterologous prime-boost immunization with the plasmid DNA and a recombinant MVA gave further enhancement of the immune responses. Thus, a multiepitope therapeutic vaccine candidate capable of stimulating those cellular immune responses thought to be essential for controlling and clearing HBV infection was successfully designed and evaluated in vitro and in HLA transgenic mice.

Functional properties of myelin oligodendrocyte glycoprotein-reactive T cells in multiple sclerosis patients and controls

Autoimmune T-cell reactivity to myelin components may be implicated in the initiation or maintenance of the inflammation leading to myelin destruction in multiple sclerosis (MS). Myelin oligodendrocyte glycoprotein (MOG), a quantitatively minor myelin protein, is an important candidate autoantigen in MS. We studied T-cell responses to recombinant MOG (extracellular domain, rMOG) and a panel of four peptides within this domain (amino acids 1-22, 34-56, 64-86 and 74-96) in MS patients and healthy controls (NS). Frequency analysis of T cells reactive to rMOG as measured by IFN-gamma ELISPOT did not reveal significant differences between MS patients and controls. MOG-reactive T-cell lines and clones (TCL/TCC) were generated by stimulating PBMC of four MS patients and three healthy subjects with a cocktail of the four MOG peptides. The functional properties of 50 MOG peptide-reactive TCL/TCC obtained were studied. All TCL were TCR alpha beta+CD4+ and 20 TCL showed reactivity to MOG peptides 1-22, 13 to 34-56, 1 to 64-86 and 16 to 74-96. No significant differences in peptide recognition were observed between MS patients and controls. The T-cell receptor (TCR) hypervariable regions of MOG-reactive TCL/TCC showed a heterogeneous usage of various TCR V(-D)-J elements. The data provide no evidence for clonal expansions within the MOG-reactive T-cell repertoire of the two study groups. Intracellular cytokine analysis demonstrated predominantly Th1-TCC (IFN-gamma+/IL-4-) in MS patients, while most MOG-reactive TCC of control subjects had a mixed Th0/Th1 phenotype. Furthermore, the MS-derived MOG-reactive TCC produced increased levels of TNF-alpha upon antigen stimulation as compared to controls. Most of the MS-derived MOG-TCC induced specific cytolysis of autologous MOG-pulsed PBMC (9/11) while none of the MOG-TCC isolated from control subjects showed this cytotoxicity (0/8). In conclusion, although the frequency of anti-MOG T cells was similar in MS patients and controls, our data indicate potential differences in the functional properties of MOG TCL in MS patients versus healthy controls which may relate to their role in the disease process.