Infliximab (RemicadeR): from bench to clinical practice. A paradigm shift in rheumatology practice

The mosaic puzzle of the therapeutic monoclonal antibodies and antibody fragments - A modular transition from full-length immunoglobulins to antibody mimetics

The use of monoclonal antibodies represents an important and efficient diagnostic and therapeutic tool in disease management and modern science but remains limited by several factors including the uneven distribution in diseased tissues as well as undesired activation of side immune reactions. Major scientific advancements including Recombinant DNA Technology, Hybridoma Technology, and Polymerase Chain Reaction have considerably impacted the use of monoclonal antibodies providing technical and effective solutions to overcome the shortcomings encountered with conventional antibodies. Initially, the introduction of antibody fragments allowed a more uniform and deeper penetration of the targeted tissue and reduced unwanted activation of Fc-mediated immune reactions. On another level, the immunogenicity of murine-derived antibodies was overcome by humanizing their encoding genes with specific sequences of human origin andtransgenic mice able to synthesize fully human antibodies were successfully created. Moreover, the advancement of genetic engineering techniques supported by the modular structure of antibody coding genes paved the way for the development of a new generation of antibody fragments with a wide spectrum of monospecific and bispecific agents. These later could be monovalent, bivalent, or multivalent, and either expressed as a single chain, assembled in multimeric forms or stringed in tandem. This has conferred improved affinity, stability, and solubility to antibody targetting. Lately, a new array of monoclonal antibody fragments was introduced with the engineering of nanobody and antibody mimetics as non-immunoglobulin-derived fragments with promising diagnostic and therapeutic applications. In this review, we decipher the molecular basis of monoclonal antibody engineering with a detailed screening of the antibody derivatives that provides new perspectives to expand the use of monoclonal fragments into previously unexplored fields.

Incidence of Infusion Reactions and Clinical Effectiveness of Intravenous Golimumab Versus Infliximab in Patients with Rheumatoid Arthritis: The Real-World AWARE Study

OBJECTIVE

Evaluate tolerability and effectiveness of golimumab-IV versus infliximab in patients with rheumatoid arthritis (RA) in a real-world setting.

METHODS

AWARE, a prospective, real-world, pragmatic, observational, multicenter, phase 4 study, enrolled RA patients when initiating golimumab-IV or infliximab. Treatment decisions were made by the treating rheumatologist. The approved doses for RA are 2 mg/kg at weeks 0, 4, then Q8W for golimumab-IV and 3 mg/kg at weeks 0, 2, 6, then Q8W (dose escalation permitted) for infliximab. A prespecified formal interim analysis was conducted. The primary endpoint was the incidence of infusion reactions (any adverse event that occurred during or within 1 h of infusion) through week 52. Major secondary endpoints were mean change from baseline in CDAI at months 6 and 12 in biologic-naïve patients (non-inferiority margin in the CDAI = 6). Baseline characteristics were adjusted using propensity scores with inverse probability of treatment weights (IPTW).

RESULTS

In the formal interim analysis (golimumab-IV, n = 479; infliximab, n = 354), the incidence of infusion reactions was significantly lower with golimumab-IV vs. infliximab (3.6 vs. 17.6%, p < 0.001, IPTW-adjusted). Among biologic-naïve patients, mean changes from baseline in CDAI at month 6 (- 9.5 golimumab-IV vs. - 10.1 infliximab) and at month 12 (- 9.4 golimumab-IV vs. - 10.1 infliximab) demonstrated non-inferiority.

CONCLUSIONS

The proportion of patients with an infusion reaction was significantly lower with golimumab-IV vs. infliximab. Among biologic-naïve patients, mean change from baseline in CDAI at months 6 and 12 was non-inferior for golimumab-IV vs. infliximab. Compared with fixed-dose golimumab-IV, infliximab dose escalation did not provide any greater improvements in CDAI for patients with RA.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT02728934.

The birth pangs of monoclonal antibody therapeutics: the failure and legacy of Centoxin

This paper examines the development and termination of nebacumab (Centoxin®), a human IgM monoclonal antibody (mAb) drug frequently cited as one of the notable failures of the early biopharmaceutical industry. The non-approval of Centoxin in the United States in 1992 generated major concerns at the time about the future viability of any mAb therapeutics. For Centocor, the biotechnology company that developed Centoxin, the drug posed formidable challenges in terms of safety, clinical efficacy, patient selection, the overall economic costs of health care, as well as financial backing. Indeed, Centocor's development of the drug brought it to the brink of bankruptcy. This article shows how many of the experiences learned with Centoxin paved the way for the current successes in therapeutic mAb development.

Infliximab and other immunomodulating drugs in patients with inflammatory bowel disease and the risk of serious bacterial infections

BACKGROUND

There remain concerns about the safety of infliximab therapy in patients with inflammatory bowel disease (IBD).

AIM

To assess the association between the initiation of infliximab and other immunomodulating drugs and the risk of serious bacterial infection in the treatment of IBD.

METHODS

We assembled a cohort study of patients with IBD, including Crohn's disease (CD) and ulcerative colitis (UC). All patients initiating an immunomodulating drug between January 2001 and April 2006 were identified in British Columbia from linked health care utilization databases. Exposure of interest was initiation of infliximab or corticosteroids compared with initiation of other immunosuppressive agents, including azathioprine, mercaptopurine (MP) and methotrexate (MTX). Outcome of interest was serious bacterial infections requiring hospitalization, including Clostridium difficile.

RESULTS

Among 10 662 IBD patients, the incidence rate of bacteriaemia ranged from 3.8 per 1000 person-years (95% confidence interval 2.1-6.2) for other immunosuppressive agents to 7.4 (3.3-19.3) for infliximab with slightly higher rate for serious bacterial infections resulting in an adjusted relative risk 1.4 (0.47-4.24). Clostridium difficile infections occurred in 0/1000 (0-5.4) among 521 infliximab initiations and 14/1000 (10.6-18.2) for corticosteroids. Corticosteroid initiation tripled the risk of C. difficile infections (RR = 3.4; 1.9-6.1) compared with other immunosuppressant agents. This corticosteroid effect was neither dose-dependent nor duration-dependent. Bacteriaemia and other serious bacterial infections were not increased by corticosteroids or infliximab (5 events).

CONCLUSIONS

In a population-based cohort of patients with IBD, we found no meaningful association between infliximab and serious bacterial infections, although some subgroups had few events. Corticosteroid initiation increased the risk for C. difficile infections in these patients.