Pharmacokinetics, pharmacodynamics, and safety of single-dose subcutaneous sarilumab with or without methotrexate in Japanese patients with rheumatoid arthritis: Two single-dose studies.

OBJECTIVES: To assess the safety and pharmacokinetics (PK) of single-dose subcutaneous (SC) sarilumab or tocilizumab SC ± methotrexate (MTX) and to assess the pharmacodynamics (PD) of sarilumab SC or tocilizumab SC monotherapy in Japanese rheumatoid arthritis (RA) patients. METHODS: TDU13402 was a randomized, double-blind, placebo-controlled, single-ascending dose Phase 1 study (NCT01850680). Twenty-four patients (6 per treatment group) received sarilumab 50, 100, or 200 mg plus MTX or placebo (2 per cohort) on Day (D) 1; PK and safety were assessed through D57. PDY14191 was a randomized, open-label, single-dose study (NCT02404558). Thirty patients (15 per arm) received sarilumab 150 mg or tocilizumab 162 mg on D1; PK, PD, and safety were assessed through D43. RESULTS: TDU13402: mean serum sarilumab exposure increased in a greater than dose proportional manner from 50 to 200 mg dose with no clinically meaningful increase in treatment-emergent adverse events (TEAEs). PDY14191: PK profiles of single-dose sarilumab 150 mg or tocilizumab 162 mg were similar; some numerical differences in PD profiles and TEAEs were observed. Neutrophil count decrease/neutropenia was the most frequently reported TEAE with sarilumab treatment in both studies. CONCLUSIONS: PK, PD, and safety profiles of single-dose sarilumab SC with/without MTX were consistent with results anticipated in Japanese patients with RA.

Discontinuation of etanercept after achievement of sustained remission in patients with rheumatoid arthritis who initially had moderate disease activity-results from the ENCOURAGE study, a prospective, international, multicenter randomized study.

OBJECTIVES: To investigate the efficacy and safety of etanercept (ETN) in patients with rheumatoid arthritis (RA) with moderate disease activity and the possibility to discontinue ETN after achieving remission. METHODS: Multicenter, randomized, and open-label study was conducted in Japan and Korea. RA patients (disease duration <5 years) with moderate disease activity despite methotrexate (MTX) treatment were allocated to either MTX or ETN + MTX (Period 1) for 12 months. Patients who achieved sustained remission defined as DAS28 < 2.6 at both 6 and 12 months in the ETN + MTX group, were randomized to either continue or discontinue ETN for 12 months (Period 2). RESULTS: A total of 222 patients were enrolled in Period 1 and clinical remission was achieved in 106/157 (67.5%) and 5/28 (17.9%) patients in the ETN + MTX and MTX groups, respectively. In Period 2, sixty-seven patients were randomized and finally 28/32 (87.5%) and 15/28 (53.6%) patients who continued or discontinued ETN maintained clinical remission. Baseline disease activity and the presence of comorbid diseases influenced the maintenance of remission after ETN discontinuation. CONCLUSIONS: ETN + MTX was efficient for RA patients with moderate disease activity into remission. After achieving sustained remission, a half of the patients who discontinued ETN could maintain remission for 1 year.

Clinical and structural remission rates increased annually and radiographic progression was continuously inhibited during a 3-year administration of tocilizumab in patients with rheumatoid arthritis: A multi-center, prospective cohort study by the Michinoku Tocilizumab Study Group.

OBJECTIVE: To evaluate the clinical and structural efficacy of tocilizumab (TCZ) during its long-term administration in patients with rheumatoid arthritis (RA). METHODS: In total, 693 patients with RA who started TCZ therapy were followed for 3 years. Clinical efficacy was evaluated by DAS28-ESR and Boolean remission rates in 544 patients. Joint damage was assessed by calculating the modified total Sharp score (mTSS) in 50 patients. RESULTS: When the reason for discontinuation was limited to inadequate response or adverse events, the 1-, 2-, and 3-year continuation rates were 84.0%, 76.8%, and 72.2%, respectively. The mean DAS28-ESR was initially 5.1 and decreased to 2.5 at 6 months and to 2.2 at 36 months. The Boolean remission rate was initially 0.9% and increased to 21.7% at 6 months and to 32.2% at 36 months. The structural remission rates (ΔmTSS/year ≤ 0.5) were 68.8%, 78.6%, and 88.9% within the first, second, and third years, respectively. The structural remission rate at 3 years (ΔmTSS ≤ 1.5) was 66.0%, and earlier achievement of swollen joint count (SJC) of 1 or less resulted in better outcomes. CONCLUSIONS: TCZ was highly efficacious, and bone destruction was strongly prevented. SJC was an easy-to-use indicator of joint destruction.

Feasibility of methotrexate discontinuation following tocilizumab and methotrexate combination therapy in patients with long-standing and advanced rheumatoid arthritis: a 3-year observational cohort study.

OBJECTIVES: Methotrexate (MTX) is associated with extensive side effects, including myelosuppression, interstitial pneumonia, and infection. It is, therefore, critical to establish whether its administration is required after achieving remission with tocilizumab (TCZ) and MTX combination therapy in patients with rheumatoid arthritis (RA). Therefore, the aim of this multicenter, observational, cohort study was to evaluate the feasibility of MTX discontinuation for the safety of these patients. METHODS: Patients with RA were administered TCZ, with or without MTX, for 3 years; those who received TCZ+MTX combination therapy were selected. After remission was achieved, MTX was discontinued without flare development in one group (discontinued [DISC] group, n = 33) and continued without flare development in another group (maintain [MAIN] group, n = 37). The clinical efficacy of TCZ+MTX therapy, patient background characteristics, and adverse events were compared between groups. RESULTS: The disease activity score in 28 joints-erythrocyte sedimentation rate (DAS28-ESR) at 3, 6, and 9 months was significantly lower in the DISC group (P < .05, P < .01, and P < .01, respectively). Further, the DAS28-ESR remission rate at 6 and 9 months and Boolean remission rate at 6 months were significantly higher in the DISC group (P < .01 for all). Disease duration was significantly longer in the DISC group (P < .05). Furthermore, the number of patients with stage 4 RA was significantly higher in the DISC group (P < .01). CONCLUSIONS: Once remission was achieved, MTX was discontinued in patients who responded favorably to TCZ+MTX therapy, despite the prolonged disease duration and stage progression.

[Approach from bedside to etiology/pathophysiology/treatment of rheumatoid arthritis].

Rheumatoid arthritis (RA) is a disease full of variety. We need to elucidate various clinical doubts for the complete cure of RA. We observed a lot of patients with human parvovirus B19 (B19) infection who developed to RA till now. We investigated B19 infection in relation with RA etiology. B19 infects persistently to immune cells through cell surface Ku80 autoantigen as a cellular receptor. We are able to detect B19 in immune cells which infiltrate in synovial tissues of patients with RA. B19 is activated in infected cells, and functional viral protein NS1 induces over production of inflammatory cytokine TNFalpha. As a result, it promotes a neutrophile activation and migration to the synovium where there are B19-infected immune cells. This may cause arthritis and create a vicious circle of chronic inflammation that develops into RA. As for the B19 persistent infection to immune cells, abnormality of anti-B19 humoral immunity may participate in imperfection of B19 neutralization of a host. It is expected the development of effective treatment that cure progressing RA from B19 infection. NS1 may be one of the candidates of therapeutic target.

Longterm Safety and Efficacy of Subcutaneous Tocilizumab Monotherapy: Results from the 2-year Open-label Extension of the MUSASHI Study.

OBJECTIVE: To evaluate the longterm safety and efficacy of subcutaneous tocilizumab (TCZ-SC) as monotherapy in patients with rheumatoid arthritis (RA). METHODS: Of 346 patients who received 24 weeks of double-blind treatment with either TCZ-SC monotherapy, 162 mg every 2 weeks (q2w); or intravenous TCZ (TCZ-IV) monotherapy, 8 mg/kg every 4 weeks; 319 patients continued to receive TCZ-SC q2w in the 84-week open-label extension (OLE) of the MUSASHI study (JAPICCTI-101117). Efficacy, safety, and immunogenicity were evaluated for all patients treated with TCZ during 108 weeks. RESULTS: The proportions of patients who achieved American College of Rheumatology 20/50/70 responses, low disease activity [28-joint Disease Activity Score (DAS28) ≤ 3.2], or remission (DAS28 < 2.6) at Week 24 were maintained until Week 108. The incidences of adverse events and serious adverse events were 498.3 and 16.9 per 100 patient-years (PY), respectively. The overall safety of TCZ-SC monotherapy was similar to that of TCZ-IV monotherapy. Rates of injection site reactions (ISR) through 108 weeks remained similar to rates through 24 weeks. ISR were mild and did not cause any patient withdrawals. No serious hypersensitivity events (including anaphylactic reactions) occurred. Anti-TCZ antibodies were present in 2.1% of patients treated with TCZ-SC monotherapy. CONCLUSION: TCZ-SC monotherapy maintained a favorable safety profile and consistent efficacy throughout the 108-week study. Like TCZ-IV, TCZ-SC could provide an additional treatment option for patients with RA.

Evaluation of anti-parvovirus B19 activity in sera by assay using quantitative polymerase chain reaction.

Human parvovirus B19 (B19) infects cells of erythroid lineage. Production of neutralizing antibodies (Abs) is indispensable for recovery from B19-related disease state. In this study, we used a convenient method to measure neutralizing activities in human sera by using a real-time quantitative PCR based assay. Erythroid cell line KU812Ep6 was incubated with test sera before infection with B19 virus. The copy number of B19-DNA in cultures was decreased in the presence of the sera from patients who recovered from acute B19 infection, whereas no decrease in B19-DNA was in cultures incubated with sera from healthy volunteers who had no B19 infection. The decrease in B19-DNA copy number was calculated and the inhibition percentage was expressed as neutralizing activity to B19. A clinical study showed that the levels of neutralizing ability were high in patients who recovered soon after acute B19 infection, but were low in some patients with a prolonged clinical course for recovery from B19 infection. This method is simple and convenient compared with methods described previously, showing its usefulness to evaluate the neutralizing activity to B19.

Human parvovirus B19 infection during the inactive stage of systemic lupus erythematosus.

A 42-year-old woman with systemic lupus erythematosus (SLE) had an episode of fever, arthralgia and anemia. In order to treat the suspected activation of SLE, the daily dose of steroid was increased, however, the anemia progressed and pancytopenia developed. Both IgM anti-B19 antibodies to human parvovirus B19 (B19) and B19 DNA were positive, and bone marrow analysis revealed pure red cell aplasia with giant proerythroblasts. High dose gamma globulin was administered and the daily dose of steroid was tapered, resulting in the improvement of her condition. B19 infection should be ruled out in cases with reactivation of autoimmune diseases.

[Comparative study of T-wave alternans, QT c dispersion and late potential for predicting ventricular tachycardia in patients with ischemic heart disease].

Ventricular tachycardia(VT) is well known as the life-threatening arrhythmia. It would be important for predicting the risk of VT to prevent sudden death caused by VT after myocardial damage such as old myocardial infarction and dilated cardiomyopathy. In this study, we examined late potential(LP), TWA alternans(TWA), and QTc dispersion(QTcd) measured by Holter ECG, in 21 patients with old myocardial infarction(OMI) and 21 patients with dilated cardiomyopathy(DCM), and evaluated these parameters in relation with the occurrence of VT on these patients. The sensitivities of LP, TWA, and QTcd in patients with OMI in relation with VT were 82%, 73%, and 82%, respectively, and those in patients with DCM were 82%, 93%, and 73%, respectively. The specificities of LP, TWA, and QTcd in patients with OMI in relation with VT were 100%, 40%, and 100%, respectively, and those in patients with DCM were 100%, 30%, and 100%, respectively. The data demonstrated that LP and TWA were the useful predictive parameters for the VT on myocardial damage such as OMI and DCM.

Intrathyroidal persistence of human parvovirus B19 DNA in a patient with Hashimoto's thyroiditis.

Previous studies suggest a role of viral infection in the development of Hashimoto's thyroiditis (HT). Here we report a patient with HT in whom human parvovirus B19 (B19) DNA has been persistently detected in the thyroid regardless of the presence or absence of B19 DNA in peripheral blood mononuclear cells. In contrast to the DNA persistence, however, VP1 capsid protein was not detected in the thyroid by immunohistochemical studies. Thyroid specimens obtained by fine needle aspiration biopsy from two patients with HT and two with Graves' disease were negative for B19 DNA. Thus, whereas a causal link between B19 infection and HT remains to be determined, B19 DNA may persist in the thyroid and B19 infection may facilitate the intrathyroidal inflammatory process in HT patients.

Human parvovirus B19 infection of monocytic cell line U937 and antibody-dependent enhancement.

Human parvovirus B19 (B19) infects human erythroid lineage cells. Accumulating evidence also shows that B19 is detectable in nonerythroid lineage cells in vivo, but the mechanism of infection is still not clear. In this study, we explored the mode of B19 infection of human monocytic cell line U937. An in vitro infection study demonstrated B19 binding of U937 and slow replication of B19-DNA with B19-NS1 mRNA transcription. B19-DNA replication in U937 was accompanied by undetectable level of B19-VP1 mRNA transcription, indicating that B19 infection of U937 cells may be abortive. Levels of B19-DNA and B19-NS1 mRNA transcription increased in the presence of anti-B19 IgG antibodies, but this effect decreased in the presence of anti-Fc receptor antibodies, showing antibody-dependent enhancement by B19 infection. Antibody-dependent enhancement also caused the increased production of TNFalpha in U937. This study is the first to suggest B19 infection of nonerythroid lineage cells with antibody-dependent enhancement.

Q fever with clinical features resembling systemic lupus erythematosus.

A 23-year-old woman with prolonged fever, rash, and pericarditis associated with high titers of antinuclear, anti-Sm, and anti-RNP antibodies was suspected of having systemic lupus erythematosus (SLE). However, we also considered infectious diseases, particularly Q fever, as the C-reactive protein level was elevated and the patient reported contact with zoo animals around two weeks before the onset. The condition responded rapidly to administration of minocycline; symptoms resolved without using steroids. Thereafter, no recurrence of the illness was observed. Titer of Coxiella burnetii antibody was high and the illness was accordingly diagnosed as acute Q fever rather than SLE.

Ku80 autoantigen as a cellular coreceptor for human parvovirus B19 infection.

Human parvovirus B19 (B19) infects human erythroid cells expressing P antigen. However, some cell lines that were positive for P antigen failed to bind B19, whereas some cell lines had an ability to bind B19 despite undetectable expression of P antigen. We here demonstrate that B19 specifically binds with Ku80 autoantigen on the cell surface. Furthermore, transfection of HeLa cells with the gene of Ku80 enabled the binding of B19 and allowed its entry into cells. Moreover, reduction of cell-surface expression of Ku80 in KU812Ep6 cells, which was a high-sensitive cell line for B19 infection, by short interfering RNA for Ku80 resulted in the marked inhibition of B19 binding in KU812Ep6 cells. Although Ku80 originally has been described as a nuclear protein, human bone marrow erythroid cells with glycophorin A or CD36, B cells with CD20, or T cells with CD3 were all positive for cell-surface expression of Ku80. B19 infection of KU812Ep6 cells and bone marrow cells was inhibited in the presence of anti-Ku80 antibody. Our data suggest that Ku80 functions as a novel coreceptor for B19 infection, and this finding may provide an explanation for the pathologic immunity associated with B19 infection.

Acute cytomegalovirus infection and transient carotid intimal-medial thickening in a young, otherwise healthy woman.

Carotid intimal-medial thickening was observed in a 23-year-old woman with acute cytomegalovirus (CMV) infection. The thickening disappeared after her recovery from the infection. As endothelial cells are common targets of CMV, this thickening suggests that CMV infection causes vascular lesions, even in otherwise healthy individuals.

Regulation of tumor necrosis factor alpha promoter by human parvovirus B19 NS1 through activation of AP-1 and AP-2.

Human parvovirus B19 frequently causes acute and chronic arthritis in adults. The molecular mechanism of B19 arthritis, however, remains poorly understood. We previously showed that the transmission of B19 from rheumatoid synoviocytes to monocytic cells is associated with enhanced secretion of tumor necrosis factor alpha (TNF-alpha), which triggers inflammation, and interleukin-6. To determine the role of B19 in the production of TNF-alpha, we focused on the function of its nonstructural protein, NS1, and established monocytic U937 lines transduced with the NS1 gene under the control of an inducible promoter. Production of TNF-alpha mRNA and protein was elevated in a manner associated with NS1 expression. Reporter assays revealed that AP-1 and AP-2 motifs on the TNF-alpha promoter were responsible for NS1-mediated up-regulation. Electrophoretic mobility shift assay showed specific binding of nuclear proteins from NS1 gene-transduced cells with the AP-1 or AP-2 probe. Antibodies against transcription factors AP-1 and AP-2 and anti-NS1 antibody inhibited the binding of nuclear proteins to the corresponding probes. These data indicate that NS1 up-regulates TNF-alpha transcription via activation of AP-1 and AP-2 in monocytic cells. The molecular mechanisms of NS1-mediated TNF-alpha expression would explain the pathogenesis of B19-associated inflammation.

Soluble CD26/dipeptidyl peptidase IV enhances transendothelial migration via its interaction with mannose 6-phosphate/insulin-like growth factor II receptor.

CD26 is a T cell surface molecule with dipeptidyl peptidase IV (DPPIV) enzyme activity in its extracellular region. In addition to its membrane form, CD26 exists in plasma as a soluble form (sCD26), which is the extracellular domain of the molecule thought to be cleaved from the cell surface. In this paper, we demonstrate that sCD26 mediates enhanced transendothelial T cell migration, an effect that requires its intrinsic DPPIV enzyme activity. We also show that sCD26 directly targets endothelial cells and that mannose 6-phosphate/insulin-like growth factor II receptor (M6P/IGFIIR) on the endothelial cell surface acts as a receptor for sCD26. Our findings therefore suggest that sCD26 influences T cell migration through its interaction with M6P/IGFIIR.

Stanniocalcin-1 as a novel marker to detect minimal residual disease of human leukemia.

Stanniocalcin is a glycoprotein hormone that regulates the calcium level in fish. We found that mRNA of human stanniocalcin 1 (STC-1) is detectable in phytohemagglutinin-stimulated T cells and in most human leukemia cell lines, suggesting a role of STC-1 for cell proliferation. This finding prompts us to study the usefulness of STC-1 for monitoring acute leukemia. The levels of STC-1 transcripts increased in patients with acute leukemia at diagnosis and relapse, as judged by quantitative real-time RT-PCR. Levels of transcripts rapidly decreased to within the cut-off levels, when the blast numbers decreased with chemotherapy. Prolonged elevation of STC-1 levels after treatment was associated with a poor prognosis. All of 7 patients relapsed 1 to 4 months after they showed an elevated level of the transcripts in clinical remission. These results indicate that STC-1 is a novel marker for minimal residual disease of acute leukemia, and for an early diagnosis of relapse.

Detection of clone-specific immunoglobulin heavy chain genes in the bone marrow of B-cell-lineage lymphoma after treatment.

In order to determine the appropriate treatment of malignant lymphoma, it is important to know the degree to which extra-nodal invasion of lymphoma cells has occurred. We amplified complementarity-determining region (CDR) III genes in 64% of lymph node samples at the onset or relapse of B-cell-lineage non-Hodgkin's lymphoma (NHL) in 22 patients. By using a clone-specific CDR III probe in each patient, we were able to detect minimal residual disease (MRD) of lymphoma cells in the bone marrow and/or blood in 9 out of 14 cases (64.2%) at the onset of the disease or relapse, whereas abnormal cells in the bone marrow and/or blood were identified by routine morphological analysis in only 4 out of 22 cases (18.2%). This indicates that extranodal invasion of malignant cells may be common in patients with NHL. In some cases, the clone-specific CDR III gene was still expressed in the samples of bone marrow and/or peripheral blood even after chemotherapy, when other markers associated with NHL were no longer expressed. Five out of six cases in this group had a worse outcome associated with NHL. On the other hand, most of the cases whose clone-specific CDR III gene was no longer expressed in the bone marrow and/or in circulation after treatment had a relatively fair prognosis. These results indicate that the detection at molecular level of MRD in extranodal organs may prove useful as a predictor of prognosis for NHL.