Pharmacokinetics and safety of single doses of tabalumab in subjects with rheumatoid arthritis or systemic lupus erythematosus.

AIMS: Two phase 1 studies evaluated the pharmacokinetics (PK), safety and biological activity of tabalumab, a human monoclonal antibody against B-cell activating factor (BAFF), administered intravenously (i.v.) or subcutaneously (s.c.) in subjects with rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE). METHODS: In study A, subjects with RA (n = 23) or SLE (n = 6) received a single i.v. dose of tabalumab (RA 0.01, 0.04, 0.125, 0.5, 2.0, and 8.0 mg kg(-1) and SLE 0.125 or 2.0 mg kg(-1) ) or placebo. In study B, subjects with RA received a single tabalumab dose i.v. (10 mg) (n = 12) or s.c. (20 mg) (n = 12). Serum tabalumab and CD20+ B cells were evaluated and safety was assessed throughout both studies. RESULTS: Tabalumab PK were non-linear across the 0.01 to 8.0 mg kg(-1) dose range. Clearance (CL) decreased from 2.9 to 0.1 l day(-1) and terminal half-life (t1/2 ) increased from about 1.6 to 25 days. Subjects with RA or SLE had similar PK. After s.c. dosing, tabalumab time to maximal concentration (tmax ) was 5.5 days. Absolute bioavailability (F) was approximately 62%. Following tabalumab dosing, CD20+ B cells transiently increased from baseline followed by a progressive decrease below baseline. CONCLUSION: A single tabalumab dose administered i.v. or s.c. was well tolerated and had non-linear CL over the dose range investigated in subjects with RA and SLE. The non-linearity likely reflects target-mediated CL due to binding to BAFF. Tabalumab showed biological activity based on changes in peripheral CD20+ lymphocyte numbers in both subjects with RA and SLE.

Sifalimumab, a human anti-interferon-α monoclonal antibody, in systemic lupus erythematosus: a phase I randomized, controlled, dose-escalation study.

OBJECTIVE: To evaluate the safety and tolerability of multiple intravenous (IV) doses of sifalimumab in adults with moderate-to-severe systemic lupus erythematosus (SLE). METHODS: In this multicenter, double-blind, placebo-controlled, sequential dose-escalation study, patients were randomized 3:1 to receive IV sifalimumab (0.3, 1.0, 3.0, or 10.0 mg/kg) or placebo every 2 weeks to week 26, then followed up for 24 weeks. Safety assessment included recording of treatment-emergent adverse events (AEs) and serious AEs. Pharmacokinetics, immunogenicity, and pharmacodynamics were evaluated, and disease activity was assessed. RESULTS: Of 161 patients, 121 received sifalimumab (26 received 0.3 mg/kg; 25, 1.0 mg/kg; 27, 3.0 mg/kg; and 43, 10 mg/kg) and 40 received placebo. Patients were predominantly female (95.7%). At baseline, patients had moderate-to-severe disease activity (mean SLE Disease Activity Index score 11.0), and most (75.2%) had a high type I interferon (IFN) gene signature. In the sifalimumab group versus the placebo group, the incidence of ≥1 treatment-emergent AE was 92.6% versus 95.0%, ≥1 serious AE was 22.3% versus 27.5%, and ≥1 infection was 67.8% versus 62.5%; discontinuations due to AEs occurred in 9.1% versus 7.5%, and death occurred in 3.3% (n=4) versus 2.5% (n=1). Serum sifalimumab concentrations increased in a linear and dose-proportional manner. Inhibition of the type I IFN gene signature was sustained during treatment in patients with a high baseline signature. No statistically significant differences in clinical activity (SLEDAI and British Isles Lupus Assessment Group score) between sifalimumab and placebo were observed. However, when adjusted for excess burst steroids, SLEDAI change from baseline showed a positive trend over time. A trend toward normal complement C3 or C4 level at week 26 was seen in the sifalimumab groups compared with baseline. CONCLUSION: The observed safety/tolerability and clinical activity profile of sifalimumab support its continued clinical development for SLE.

A Phase 1, randomized, double-blind, placebo-controlled, single- and multiple-dose escalation study to evaluate the safety and pharmacokinetics/pharmacodynamics of PF-06835375, a C-X-C chemokine receptor type 5 directed antibody, in patients with systemic lupus erythematosus or rheumatoid arthritis.

BACKGROUND: The objective of this study was to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of PF­06835375, a potent selective afucosyl immunoglobulin G1 antibody targeting C-X-C chemokine receptor type 5 (CXCR5) that potentially depletes B cells, follicular T helper (Tfh) cells, and circulating Tfh-like (cTfh) cells, in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). METHODS: This first-in-human, multicenter, double-blind, sponsor-open, placebo-controlled Phase 1 study recruited patients aged 18-70 years with SLE or RA. In Part A, patients received single doses of intravenous PF-06835375 (dose range: 0.03-6 mg) or placebo in six sequential single ascending dose (SAD) cohorts. In Part B, patients received repeat doses of subcutaneous PF-06835375 (dose range: 0.3-10 mg) or placebo on Days 1 and 29 in five multiple ascending dose (MAD) cohorts. Tetanus/Diphtheria (Td) and Meningococcal B (MenB/Trumenba™) vaccines were administered at Day 4 (Td and MenB) and Week 8 (MenB only) to assess PF-06835375 functional effects. Endpoints included treatment-emergent adverse events (TEAEs), pharmacokinetic parameters, pharmacodynamic effects on B and cTfh cells, and biomarker counts, vaccine response, and exploratory differential gene expression analysis. Safety, pharmacokinetic, and pharmacodynamic endpoints are summarized descriptively. The change from baseline of B and Tfh cell-specific genes over time was calculated using a prespecified mixed-effects model, with a false discovery rate < 0.05 considered statistically significant. RESULTS: In total, 73 patients were treated (SAD cohorts: SLE, n = 17; RA, n = 14; MAD cohorts: SLE, n = 22; RA, n = 20). Mean age was 53.3 years. Sixty-two (84.9%) patients experienced TEAEs (placebo n = 17; PF-06835375 n = 45); most were mild or moderate. Three (9.7%) patients experienced serious adverse events. Mean t1/2 ranged from 3.4-121.4 h (SAD cohorts) and 162.0-234.0 h (MAD cohorts, Day 29). B and cTfh cell counts generally showed dose-dependent reductions across cohorts (range of mean maximum depletion: 67.3-99.3%/62.4-98.7% [SAD] and 91.1-99.6%/89.5-98.1% [MAD], respectively). B cell-related genes and pathways were significantly downregulated in patients treated with PF-06835375. CONCLUSIONS: These data support further development of PF-06835375 to assess the clinical potential for B and Tfh cell depletion as a treatment for autoimmune diseases. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03334851.

Selective expansion of regulatory T cells by NKTR-358 in healthy volunteers and patients with systemic lupus erythematosus.

Objective: To evaluate NKTR-358, a polyethylene glycol-interleukin-2 conjugate composition designed to selectively induce regulatory T cells (Tregs), in first-in-human studies. Methods: Healthy volunteers and patients with systemic lupus erythematosus (SLE) received single- or multiple-dose (biweekly) NKTR-358 or placebo in two sequential, randomized, phase 1 studies (single ascending dose [SAD; NCT04133116] and multiple ascending dose [MAD; NCT03556007]). Primary objectives were safety and tolerability; secondary objectives included pharmacokinetics (PK) and immune effects of NKTR-358; exploratory objectives included effects on SLE disease activity. Results: There were eight ascending dose cohorts in the SAD study (0.3-28.0 µg/kg: n = 76; placebo: n = 24) and four in the MAD study (3-24.0 µg/kg: n = 36; placebo: n = 12). Most adverse events (AEs) were grade 1-2 injection-site reactions, with no treatment-related serious or severe AEs, or deaths. PK data showed dose proportionality and prolonged exposure (mean half-life: 7.4-12.9 days). Dose-dependent, selective, and sustained increases in percentages and absolute numbers of total CD4+ Tregs and CD25bright Tregs were observed, with no significant changes in conventional CD4+ and CD8+ T cells, and low-level increases in natural killer cells. At the highest doses tested, administration of NKTR-358 resulted in a 12-17-fold increase in CD25bright Tregs over baseline that was sustained for 20-30 days. Conclusion: NKTR-358 was well tolerated, had a suitable PK profile for biweekly dosing, and led to marked and selective dose-dependent increases in CD25bright Tregs, with no significant changes in conventional T cells. These results provide strong support for further testing in SLE and other inflammatory diseases.

Safety and Biological Activity of Rozibafusp alfa, a Bispecific Inhibitor of Inducible Costimulator Ligand and B Cell Activating Factor, in Patients With Rheumatoid Arthritis: Results of a Phase 1b, Randomized, Double-Blind, Placebo-Controlled, Multiple Ascending Dose Study.

OBJECTIVE: To assess the safety and biological activity of rozibafusp alfa, a first-in-class bispecific antibody-peptide conjugate targeting inducible costimulator ligand (ICOSL) and B cell activating factor (BAFF), in patients with rheumatoid arthritis (RA). METHODS: This phase 1b, double-blind, placebo-controlled, multiple ascending dose study included 34 patients (18-75 years; 82.4% female) with active RA (Disease Activity Score of 28 joints-C-reactive protein [DAS28-CRP] >2.6, on stable methotrexate) randomized 3:1 to receive rozibafusp alfa (n = 26, in four ascending dose cohorts of 70, 140, 210, and 420 mg) or a placebo (n = 8) subcutaneously once every 2 weeks for 10 weeks (six total doses), with 24 weeks of follow-up. The primary end point was the incidence of treatment-emergent adverse events (TEAEs). Additional assessments included serum pharmacokinetics (PK), pharmacodynamics (PD), immunogenicity, and RA disease activity measures (DAS28-CRP, Patient Global Assessment of Disease, and Physician Global Assessment of Disease). RESULTS: TEAEs occurred in 96.2% and 87.5% of patients receiving rozibafusp alfa and the placebo, respectively; most were mild or moderate in severity. Two (7.7%) patients treated with rozibafusp alfa reported serious TEAEs; none were considered treatment related. Multiple doses of rozibafusp alfa showed nonlinear PK (mean t1/2  = 4.6-9.5 days) and dose-related, reversible PD (>90% ICOSL receptor occupancy in 210- and 420-mg cohorts; reduction in naïve B cells and increase in memory B cells in all cohorts). Five (20%) patients developed anti-rozibafusp alfa antibodies, with no apparent impact on safety. RA disease activity showed greater numerical improvement from baseline with rozibafusp alfa versus the placebo in the 210- and 420-mg cohorts. CONCLUSION: Multiple ascending doses of rozibafusp alfa were well tolerated, with PK and PD reflecting dual ICOSL and BAFF blockade. Findings support further clinical evaluation of rozibafusp alfa in autoimmune disease.

Safety profile and clinical activity of sifalimumab, a fully human anti-interferon α monoclonal antibody, in systemic lupus erythematosus: a phase I, multicentre, double-blind randomised study.

BACKGROUND: Type I interferons (IFNs) appear to play a central role in disease pathogenesis in systemic lupus erythematosus (SLE), making them potential therapeutic targets. METHODS: Safety profile, pharmacokinetics, immunogenicity, pharmacodynamics and clinical activity of sifalimumab, an anti-IFNα monoclonal antibody, were assessed in a phase I, multicentre, randomised, double-blind, dose-escalation study with an open-label extension in adults with moderately active SLE. SUBJECTS: received one intravenous dose of sifalimumab (n=33 blinded phase, 0.3, 1, 3, 10 or 30 mg/kg; n=17 open-label, 1, 3, 10 or 30 mg/kg) or placebo (n=17). Each phase lasted 84 days. RESULTS: Adverse events (AEs) were similar between groups; about 97% of AEs were grade 1 or 2. All grade 3 and 4 AEs and all serious AEs (2 placebo, 1 sifalimumab) were deemed unrelated to the study drug. No increase in viral infections or reactivation was observed. Sifalimumab caused dose-dependent inhibition of type I IFN-induced mRNAs (type I IFN signature) in whole blood and corresponding changes in related proteins in affected skin. Exploratory analyses showed consistent trends toward improvement in disease activity in sifalimumab-treated versus placebo-treated subjects. A lower proportion of sifalimumab-treated subjects required new or increased immunosuppressive treatments (12% vs 41%; p=0.03) and had fewer Systemic Lupus Erythematosus Disease Activity Index flares (3% vs 29%; p=0.014). CONCLUSIONS: Sifalimumab had a safety profile that supports further clinical development. This trial demonstrated that overexpression of type I IFN signature in SLE is at least partly driven by IFNα, and exploratory analyses suggest that IFNα inhibition may be associated with clinical benefit in SLE. Trial registration number NCT00299819.

Investigation of Potential Drug-Drug Interactions between Peficitinib (ASP015K) and Methotrexate in Patients with Rheumatoid Arthritis.

BACKGROUND: Methotrexate is frequently used to treat rheumatoid arthritis. Peficitinib (ASP015K; Smyraf®), an oral Janus kinase inhibitor indicated for the treatment of rheumatoid arthritis, may be coadministered with methotrexate. OBJECTIVE: The objective of this study was to investigate potential drug-drug interactions of peficitinib with methotrexate and the short-term safety of coadministration. PATIENTS AND METHODS: This phase I, open-label, single-sequence study included patients with rheumatoid arthritis taking a stable dose of methotrexate. Patients received their prescribed methotrexate dose (Day 1) and then peficitinib (100 mg) twice daily from Day 3 until the morning of Day 9; a second methotrexate dose was coadministered with peficitinib on Day 8. Serial blood samples were collected for methotrexate concentration after dosing on Days 1 (methotrexate alone) and 8 (methotrexate plus peficitinib) and for peficitinib concentration after dosing on Days 7 (peficitinib alone) and 8 (methotrexate plus peficitinib). Pre-dose concentrations of peficitinib were measured (Days 3-8). RESULTS: Peficitinib concentrations reached steady state on Day 5. Administration of peficitinib did not result in changes to methotrexate area under the concentration-time curve from time zero to infinity or maximum observed concentration following a methotrexate dose (15-25 mg), and there was no significant effect of methotrexate (15-25 mg) on peficitinib area under the concentration-time curve within a 12-hour dosing interval. There were no new tolerability or safety signals after coadministration of peficitinib and methotrexate. One patient experienced two serious adverse events and withdrew from the study without receiving peficitinib. CONCLUSIONS: Pharmacokinetic results showed no significant interactions between peficitinib and methotrexate. CLINICALTRIALS. GOV IDENTIFIER: NCT01754805.

Examining the relationship between bone mineral density and fracture risk reduction during pharmacologic treatment of osteoporosis.

Osteoporosis is a skeletal disorder characterized by compromised bone strength that predisposes the patient to an increased risk for fracture. Elements of bone strength include bone mineralization, architecture, turnover, size, and bone mineral density (BMD). Measurement of BMD is the most readily available, noninvasive method for assessing osteoporotic fracture risk and is used by the World Health Organization for diagnostic purposes. Because low BMD is predictive of increased fracture risk, it was believed that changes in BMD during pharmacologic therapy for osteoporosis would strongly predict observed fracture risk reductions. We examined the relationship between changes in BMD and reduction in fracture risk during pharmacologic therapy in postmenopausal women with osteoporosis. The correlation between BMD increases and fracture risk reduction during treatment is not consistent; larger increases in BMD do not necessarily correlate with greater reductions in fracture risk. Multiple factors, in addition to BMD, appear to contribute to the increased bone strength and decreased fracture risk achieved with approved drug therapies for osteoporosis. Until the exact relationship of these factors is fully understood, clinicians should continue to evaluate drug efficacy for osteoporosis based on the fracture risk reductions from well-designed clinical trials.

A Phase 1 Dose-Escalation Study of ASP2409, a Selective T-Cell Costimulation Inhibitor, in Stable Rheumatoid Arthritis Patients on Methotrexate Therapy.

ASP2409 represents a new class of CTLA4-Ig molecules with higher binding avidity and selectivity to CD86. This first-in-human study was to assess the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics of ASP2409 in stable rheumatoid arthritis patients on methotrexate therapy with a randomized, double-blind, placebo-controlled dose-escalation study design. Patients were enrolled and randomized in each of 8 dose-escalation cohorts ranging from 0.001 to 3.0 mg/kg to receive either ASP2409 or placebo in a sequential manner. Escalation to higher dose levels occurred in the absence of dose-limiting toxicity. A total of 57 patients completed the study. ASP2409 showed nonlinear PK over the dose range of 0.01 to 3.0 mg/kg following a single intravenous administration, indicating target-mediated drug disposition. Area under the concentration-time curve (AUC) and maximum concentration (Cmax ) increased at a greater than dose-proportional rate. The half-life of ASP2409 increased dose dependently and ranged from 1.57 to 6.68 days. ASP2409 showed a dose-dependent increase in the extent and duration of CD86 receptor occupancy. There were no clinically relevant safety issues up to a single dose of 3.0 mg/kg. No maximum tolerated dose was reached. The incidence and duration of antidrug antibodies did not correlate with adverse events. ClinicalTrials.gov identifier: NCT02171143.

Pharmacokinetics, Pharmacodynamics, Safety, and Tolerability of ASP2408, a Potent Selective T-Cell Costimulation Modulator After Single and Multiple Ascending Doses in Healthy Volunteers and RA Patients.

ASP2408 is a next-generation anti-cytotoxic T lymphocyte antigen-4 fusion protein engineered for improved CD86 binding affinity as a treatment for rheumatoid arthritis (RA). In 72 healthy subjects (n = 6/treatment), ASP2408 was administered as single ascending doses intravenously at 0.003 to 10.0 mg/kg or subcutaneously at 0.3 to 3.0 mg/kg. It showed decreased clearance and prolonged half-life with increasing doses, consistent with target-mediated disposition. The apparent bioavailability was 36.3%-56.7% across single subcutaneous doses. Sixteen RA patients (n = 8/treatment) on stable methotrexate received 3 × 3.0 mg/kg subcutaneously every 4 weeks or every 2 weeks. Similar to single-dose treatment, ASP2408 concentrations peaked 2 to 3 days postdose, with a median t1/2 of approximately 8 days. Using CD86 receptor occupancy (RO) as a mechanistic biomarker, ASP2408 demonstrated dose-dependent binding to its target. ASP2408 3.0 mg/kg subcutaneously every 4 weeks and every 2 weeks led to a mean %CD86 RO ≥ 74.7% and ≥ 81.5%, respectively, within each dosing interval. ASP2408 was well tolerated across studies with no evidence of dose-limiting toxicity or clinically significant changes in clinical laboratory test results, vital signs, or 12-lead electrocardiograms. ASP2408 elicited antidrug antibodies in the majority of patients, but with no clinical sequelae.

Adding ultralow-dose naltrexone to oxycodone enhances and prolongs analgesia: a randomized, controlled trial of Oxytrex.

UNLABELLED: Oxytrex is a novel drug that combines oxycodone with ultralow-dose naltrexone, an opioid antagonist. Ultralow-dose opioid antagonists have been demonstrated to enhance and prolong opiate analgesia and alleviate opioid tolerance and withdrawal in rodents. This 3-week, Phase II clinical trial assessed safety and analgesic efficacy of Oxytrex in patients with moderate to severe pain from osteoarthritis. Patients with a pain score > or =5 received placebo, oxycodone 4 times a day (qid), Oxytrex qid, or Oxytrex twice a day (bid). All active treatment groups received the same total daily dose and dose escalation of oxycodone starting at 10 and ending at 40 mg/day. Importantly, the Oxytrex bid group received a lower daily dose of naltrexone than Oxytrex qid (0.002 vs 0.004 mg/day). Oxytrex bid produced a 39% reduction in pain intensity, which was significantly greater than that of placebo (P < .001), oxycodone qid (P = .006), and Oxytrex qid (P = .003). Oxytrex bid was also superior to placebo in quality of analgesia (P = .002), duration of pain control each day (P = .05), patients' global assessments (P = .04), and the Western Ontario and MacMaster Universities Osteoarthritis Index total score (P = .03). The incidence of side effects was comparable between active treatments. In this Phase II dose-ranging study, Oxytrex bid demonstrated greater pain relief with a more convenient dosing schedule compared to oxycodone qid. PERSPECTIVE: Preclinical data have shown ultralow-dose opioid antagonists to enhance and prolong opioid analgesia while reducing analgesic tolerance and physical dependence. Recent molecular pharmacology data show a mechanism of action to be the prevention of aberrant G protein coupling by opioid receptors that underlies opioid tolerance and dependence.

MTRX1011A, a humanized anti-CD4 monoclonal antibody, in the treatment of patients with rheumatoid arthritis: a phase I randomized, double-blind, placebo-controlled study incorporating pharmacodynamic biomarker assessments.

INTRODUCTION: The purpose of this study was to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of the humanized anti-CD4 monoclonal antibody MTRX1011A in a randomized, double-blind placebo-controlled Phase 1 study in patients with rheumatoid arthritis (RA). METHODS: In the single ascending dose (SAD) portion of the study, patients received single doses of a placebo or MTRX1011A at 0.3, 1.0, 3.5 and 7.0 mg/kg intravenously (i.v.) or 1.0 and 3.5 mg/kg subcutaneously (s.c.), followed by five weeks of evaluation. In the multi-dose (MD) portion of the study, placebo or MTRX1011A was administered weekly for eight doses at 1.5 or 3.5 mg/kg s.c., or 5 mg/kg i.v., followed by eight weeks of evaluation. RESULTS: MTRX1011A was well tolerated in the SAD phase up to 7 mg/kg i.v. and in the MD phase up to 1.5 mg/kg s.c.. At weekly doses of 3.5 mg/kg s.c. and 5 mg/kg i.v., a moderate pruritic papular rash was observed in some MTRX1011A-treated patients, which was considered a dose-limiting toxicity for this clinical indication. No serious adverse events occurred in any cohort. Reduction in disease activity was modest. PD assessments demonstrated that MTRX1011A induced a dose-dependent down-modulation of CD4 expression on peripheral blood CD4 T cells, CD4 receptor occupancy, increases in serum sCD4-MTRX1011A complexes and up-regulation of CD69 on T cells, but was non-depleting. CONCLUSIONS: The maximum tolerated dose of MTRX1011A was 1.5 mg/kg SC administered weekly. At this dose MTRX1011A did not achieve maximum PD activity expected to be required for reduction in disease activity.

Evaluation of the efficacy and safety of pamapimod, a p38 MAP kinase inhibitor, in a double-blind, methotrexate-controlled study of patients with active rheumatoid arthritis.

OBJECTIVE: To determine the efficacy and safety of pamapimod (a selective inhibitor of the alpha-isoform of p38 MAP kinase) as monotherapy in comparison with methotrexate (MTX) treatment in adult patients with active rheumatoid arthritis (RA). METHODS: Patients were randomly assigned to 1 of 4 treatment groups and received 12 weeks of double-blind treatment. One group received MTX (7.5 mg/week with planned escalation to 20 mg/week), and 3 groups received pamapimod (50, 150, or 300 mg) once daily. The primary efficacy end point was the proportion of patients meeting the American College of Rheumatology 20% improvement criteria (achieving an ACR20 response) at 12 weeks. Secondary end points included ACR50 and ACR70 responses, change from baseline in the Disease Activity Score in 28 joints (DAS28), categorical analyses of DAS28/European League Against Rheumatism response, and change from baseline in each parameter of the ACR core set of measures. Safety monitoring included recording of adverse events (AEs), laboratory testing, immunology assessments, administration of electrocardiograms, and assessment of vital signs. RESULTS: Patients assigned to receive MTX and pamapimod had similar demographics and baseline characteristics. At week 12, fewer patients taking pamapimod had an ACR20 response (23%, 18%, and 31% in the 50-, 150-, and 300-mg groups, respectively) compared with patients taking MTX (45%). Secondary efficacy end points showed a similar pattern. AEs were typically characterized as mild and included infections, skin disorders, and dizziness. Pamapimod was generally well tolerated, but the 300-mg dose appeared to be more toxic than either the 2 lower doses or MTX. CONCLUSION: The present results showed that pamapimod was not as effective as MTX in the treatment of active RA.