Impact of Glycosylation on the Local Backbone Flexibility of Well-Defined IgG1-Fc Glycoforms Using Hydrogen Exchange-Mass Spectrometry

We have used hydrogen exchange–mass spectrometry to characterize local backbone flexibility of 4 well-defined IgG1-Fc glycoforms expressed and purified from Pichia pastoris, 2 of which were prepared using subsequent in vitro enzymatic treatments. Progressively decreasing the size of the N-linked N297 oligosaccharide from high mannose (Man8-Man12), to Man5, to GlcNAc, to nonglycosylated N297Q resulted in progressive increases in backbone flexibility. Comparison of these results with recently published physicochemical stability and Fcγ receptor binding data with the same set of glycoproteins provide improved insights into correlations between glycan structure and these pharmaceutical properties. Flexibility significantly increased upon glycan truncation in 2 potential aggregation-prone regions. In addition, a correlation was established between increased local backbone flexibility and increased deamidation at asparagine 315. Interestingly, the opposite trend was observed for oxidation of tryptophan 277 where faster oxidation correlated with decreased local backbone flexibility. Finally, a trend of increasing C'E glycopeptide loop flexibility with decreasing glycan size was observed that correlates with their FcγRIIIa receptor binding properties. These well-defined IgG1-Fc glycoforms serve as a useful model system to identify physicochemical stability and local backbone flexibility data sets potentially discriminating between various IgG glycoforms for potential applicability to future comparability or biosimilarity assessments.     

Vascular endothelial growth factor (VEGF) antibody significantly increases the risk of hand–foot skin reaction to multikinase inhibitors (MKIs): A systematic literature review and meta‐analysis

With the use of multikinase inhibitors (MKIs) having emerged in recent years, skin toxicities such as hand–foot skin reaction (HFSR) are primary side effects, and they lack effective prediction methods. Here, we updated a previous systematic review by establishing a meta‐analysis of the risk of developing HFSR among patients receiving MKIs and antivascular endothelial growth factor antibody. Publications from PubMed and abstracts presented at the American Society of Clinical Oncology Annual Meeting up to February 5, 2015, were searched to identify relevant studies, and a total of 236 patients with metastatic tumours in nine trials were included for analysis. In the meta‐analysis, the pooled incidence rates of all‐grade and high‐grade HFSR among patients who received the combination therapy were 56.9% [95% confidence interval (CI), 45%‐71.1%] and 14.3% (95% CI, 9%‐24.2%), respectively, with significant differences observed with MKI monotherapy (P < .05). Further subgroup analysis demonstrated that increasing the dosages of bevacizumab (77.8% vs 51.1%, P = .04) and MKIs (64.3% vs 52.6%, P = .02) significantly increased HFSR incidence. Moreover, combination with chemotherapy exerted a minimal effect on HFSR risk (61% vs 55.3%, P = .5). This updated review and meta‐analysis confirm the increased risk of HFSR incidence due to the use of MKIs and antivascular endothelial growth factor antibody. Thus, using these therapies requires safety standards.     

过滤对一种IgG2亚型EGFR单抗中不溶性微粒的影响

目的：探讨过滤操作对一种免疫球蛋白G2（immunoglobin G2,IgG2）亚型表皮生长因子受体（epidermal growth factor receptor,EGFR）单克隆抗体（单抗）生物类似药（similar biotherapeutic product,SBP）候选药中不溶性微粒的影响。方法：利用微流数字成像（microflow digital imaging,MDI）技术对某厂家生产的IgG2亚型EGFR单抗SBP候选药与其原研药（reference biotherapeutic product,RBP）中不同粒径的不溶性微粒进行比较;采用0.22 μm的滤器对EGFR单抗SBP候选药进行过滤,并采用MDI法立即对不同粒径和性质的不溶性微粒进行检测和分析;再将过滤后的EGFR单抗SBP候选药在室温静置2 h,并采用MDI法对不同粒径和性质的不溶性微粒进行检测和分析。结果：某IgG2亚型EGFR单抗SBP候选药中不同粒径的不溶性微粒数量明显高于RBP;用0.22 μm的滤器过滤后,EGFR单抗SBP候选药中的不溶性微粒数由8.51×10⁵粒·mL^-1降为1.52×10⁴粒·mL^-1,且主要成分蛋白聚体、气泡和纤维均明显减少;室温静置2 h后,其中的不溶性微粒数由1.52×10⁴粒·mL^-1增加至3.23×10⁴粒·mL^-1,且增加的微粒主要为蛋白聚体。结论：与原研药相比,该EGFR单抗SBP候选药蛋白聚体水平较高,过滤后有明显改善,但随着放置时间延长,蛋白聚体含量又有明显增加。这提示我们需加强研发,以提高SBP候选药的产品质量、安全性和有效性。     

IPH4102, a monoclonal antibody directed against the immune receptor molecule KIR3DL2, for the treatment of cutaneous T-cell lymphoma

Introduction: Therapeutic options for mycosis fungoides and Sézary syndrome include a variety of immunomodulatory, epigenetic, and cytotoxic options; however, none has been demonstrated to be efficacious for all patients, or to deliver deep and durable responses to the majority of patients. In this review, we examine the monoclonal antibody, IPH4102, a novel agent for the treatment of cutaneous T-cell lymphoma.

Areas covered: In this review, we examine data demonstrating the tissue specificity of KIR3DL2 receptor, which is highly expressed on the malignant cells in cutaneous T-cell lymphoma, including mycosis fungoides and Sézary syndrome. This specificity has led to the development of the agent IPH4102. Preclinical data showing efficacy of IPH4102 in vivo are outlined, as well as the results from Phase I clinical trials, which suggest that the agent is both efficacious and well-tolerated. Larger scale clinical trials are to follow.

Expert Opinion: We examine the putative benefit of IPH4102 in comparison to established agents already in the clinic, highlighting its efficacy and relative safety. We also examine possible directions that may better define the role of IPH4102 in the treatment of T-cell lymphoma in the future.     

Investigational therapies targeting CD37 for the treatment of B-cell lymphoid malignancies

Introduction: While chemotherapy still remains a cornerstone of oncologic therapy, immunotherapy with monoclonal antibodies has steadily improved the treatment strategy for several hematologic malignancies. New treatment options need to be developed for relapsed and refractory non-Hodgkin lymphoma (NHL) patients. Currently, novel agents targeting specific molecules on the surface of lymphoma cells, such as anti-CD37 antibodies, are under considerable investigation. Here we report on anti-CD37 targeting for the treatment of patients with B-cell NHL.

Areas covered: CD37 seems to be the perfect therapeutic target in patients with NHL. The CD37 antigen is abundantly expressed in B-cells, but is absent on normal stem cells and plasma cells. It is hoped that anti-CD37 monoclonal antibodies will increase the efficacy and reduce toxicity in patients with both newly diagnosed and relapsed and refractory disease. Recent clinical trials have shown promising outcomes for these agents, administered both as monotherapy and in combination with standard chemotherapeutics.

Expert opinion: The development of new therapeutic options might help to avoid cytotoxic chemotherapy entirely in some clinical settings. This article presents the latest state of the art on the new treatment strategies in NHL patients. It also discusses recently approved agents and available clinical trial data.     

A safety evaluation of evolocumab

Introduction: Evolocumab is an injectable, fully human monoclonal antibody and a member of the newest class of low density lipoprotein cholesterol (LDL-C) lowering agents called proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors. The PCSK9 inhibitors are the most significant advance in lipid therapy since the introduction of the first statin 30 years ago.

Areas covered: The PCSK9 monoclonal antibodies have demonstrated a consistently high LDL-C lowering efficacy with and without statins and/or other lipid lowering therapies (LLT). LDL-C levels achieved with these agents are lower than has ever been possible before. This review will focus on the overall safety of evolocumab including cognitive impairment, very low LDL-C levels, new onset diabetes and glucose abnormalities, effect on vitamin E and steroid hormones, liver and muscle abnormalities, and immunogenicity and injection site reactions. The phase II and III clinical trials had relatively low patient-years of exposure, but the open label extension studies and the recently published outcomes trial, FOURIER, will be the focus of this paper. The safety profile of evolocumab to date is remarkable and extremely encouraging as will be demonstrated.

Expert opinion: The PCSK9 inhibitors will be responsible for a new era in lipid therapy that will expand our knowledge of lipid levels and cardiovascular disease (CVD) prevention with an efficacy and safety profile not previously available in clinical practice.     

A comparative study between outbred and inbred rat strains for the use in in vivo IPV potency testing

In vivo potency testing of inactivated poliovirus vaccines (IPV) is generally performed in rats, although no systematic investigation has identified the most appropriate rat strain for anti-poliovirus antibody quantification. We investigated humoral immune responses to IPV in five different rat strains to identify the most suitable strain. Three outbred (Wistar, Wistar Hannover, Sprague-Dawley) and two inbred rat strains (Fisher 344, Wistar Furth) were immunized intramuscularly with a full or one-fifth human dose of commercial IPV. Anti-poliovirus neutralizing antibody (NA) titers were measured using Salk and Sabin virus neutralizing assays. Post-vaccination responses varied between strains; inbred strains showed greater animal-to-animal variation in NA responses than outbred strains. Virus NA titers persisted for 9 weeks with little reduction in the response. The outbred Wistar rat model was identified as the preferred strain for IPV potency testing based on its capacity to produce high, dose-dependent anti-poliovirus NA responses, with low animal-to-animal variation.     

Immunogenicity and safety of one or two doses of the quadrivalent meningococcal vaccine MenACWY-TT given alone or with the 13-valent pneumococcal conjugate vaccine in toddlers: A phase III,open-label,randomised study

BackgroundWe evaluated the immunogenicity and safety of 1 and 2 doses of quadrivalent meningococcal serogroup A, C, W and Y tetanus toxoid-conjugate vaccine (MenACWY-TT) given alone or co-administered with 13-valent pneumococcal conjugate vaccine (PCV13) in toddlers.MethodsIn this phase III, open-label, controlled, multicentre study (NCT01939158), healthy toddlers aged 12–14 months were randomised into 4 groups to receive 1 dose of MenACWY-TT at month (M) 0 (ACWY_1), 2 doses of MenACWY-TT at M0 and M2 (ACWY_2), MenACWY-TT and PCV13 at M0 (Co-ad), or PCV13 at M0 and MenACWY-TT at M2 (PCV13/ACWY). Immune responses were assessed 1 month post-each vaccination. Solicited and unsolicited symptoms were recorded for 4 and 31 days post-each vaccination, respectively; serious adverse events (SAEs) and new onset of chronic illnesses (NOCIs) up to M9 from first vaccination.Results802 toddlers were vaccinated. Post-dose 1 of MenACWY-TT, ≥92.8% of toddlers had rSBA titres ≥1:8, and ≥62.5% had hSBA titres ≥1:4 for each meningococcal serogroup. Post-dose 2 of MenACWY-TT, rSBA titres ≥1:8 were observed in ≥98.0% and hSBA titres ≥1:4 in ≥95.3% of toddlers. Percentages of toddlers with hSBA titres ≥1:4 were higher after 2 doses versus 1 dose of MenACWY-TT for MenW (97.1% versus 62.5–68.9%) and MenY (95.3% versus 64.3–67.6%). Non-inferiority of immune responses to co-administered MenACWY-TT and PCV13 over their separate administration was demonstrated. AEs incidence was comparable among groups. SAEs were reported for 4.9%, 5.1%, 5.5% and 7.5%, and NOCIs for 2.0%, 3.0%, 0.5% and 3.5% of toddlers in the ACWY_1, ACWY_2, Co-ad and PCV13/ACWY groups, respectively; 4 SAEs reported in 3 toddlers were vaccine-related. Two fatal vaccine-unrelated SAEs were reported.ConclusionMenACWY-TT was immunogenic when administered as a single dose at 12–14 months of age. A second dose in toddlers increased hSBA responses against MenW and MenY. MenACWY-TT and PCV13 can be co-administered without impairing the immunogenicity or safety profile of either vaccine.     

Vaccination of sheep with Quil-A® adjuvant expands the antibody repertoire to the Fasciola MF6p/FhHDM-1 antigen and administered together impair the growth and antigen release of flukes

Fasciolosis continues to be a major cause of economic losses in the livestock industry and a growing threat to humans. The limited spectrum of effective anthelmintics and the appearance of resistances urge the need for developing an effective vaccine. Most studies have been focused on the use of TH₁-polarizing adjuvants and the use of recombinant Fasciola critical molecules and, despite the efforts, no reproducible protections have been achieved. The F. hepatica MF6p/FhHDM-1 protein is a heme-binding protein also reported to have immunomodulatory properties, constituting a promising target for vaccination and/or as target for the development of new flukicides. Thus, in this study, we investigated the effects of the TH₁-polarizing adjuvant Quil A® on sheep immune response to MF6p/FhHDM-1, and the vaccine potential of both native and synthetic forms of this protein against ovine fasciolosis. Subcutaneous injection of Quil A® alone, i.e., without co-injecting any antigen, expands the antibody repertoire to MF6p/FhHDM-1 triggered by a subsequent primoinfection with metacercariae. This effect was not observed with aluminum hydroxide, the most frequently adjuvant used in commercial vaccines. On the other hand, vaccination with synthetic MF6p/FhHDM-1 in Quil A® prompted a 2–4-week delay in the antibody response induced in sheep by a challenge experimental infection. Moreover, fluke populations stablished showed stunted growth and low antigen release probably due to reduced metabolic activity. These observations suggest that primary circulating antibodies induced by the immunization had harmful effects on fluke development. Such effects could not be demonstrated to be associated to TH₁ immune response linked events (production of IgG₂ isotype antibodies and IFN-γ).     

2015年哈尔滨市大学新生风疹抗体水平调查

目的 了解2015年哈尔滨市大学新生风疹抗体水平,为制定哈尔滨市风疹防控策略提供依据。方法 采用多阶段随机抽样方法。在哈尔滨市南岗区、香坊区和呼兰区3个区开展监测工作,每个区抽取3所高校、共计9所高校作为本次调查的监测点。应用酶联免疫法对在9所高校随机抽取1 089名大学新生的血清风疹IgG抗体进行检测,将不同年龄、性别、生源地、免疫史学生的风疹抗体进行比较。结果 1 089名大学新生中,风疹抗体阳性率为83.01%;男性风疹抗体阳性率为82.60%,女性风疹抗体阳性率为83.39%,差异无统计学意义(χ²=0.12,P>0.05);有风疹疫苗免疫史的调查对象风疹抗体阳性率为85.27%,无疫苗免疫史的调查对象风疹抗体阳性率为76.47%,差异有统计学意义(χ²=10.94,P=0.001);各年龄组间以23~25岁大学新生风疹抗体阳性率最低为45%(χ²=29.37,P＜0.001)。不同生源地本省风疹抗体阳性率低于外省(χ²=5.10,P=0.024)。不同民族、学校、既往是否患风疹其风疹抗体阳性率差异均无统计学意义(均P>0.05)。结论 2015年哈尔滨市大学新生风疹抗体阳性率整体较高,但大年龄人群仍具罹患风疹的风险;应开展针对大年龄人群,特别是育龄期女性的风疹疫苗的补充免疫工作。