Vaccine responses in patients with rheumatoid arthritis treated with certolizumab pegol: results from a single-blind randomized phase IV trial.

OBJECTIVE: To evaluate the humoral immune response to pneumococcal and influenza vaccination in adults with rheumatoid arthritis (RA) receiving certolizumab pegol (CZP). METHODS: In this 6-week, single-blind, placebo-controlled trial with optional 6-month open-label extension (NCT00993668), patients were stratified by concomitant methotrexate (MTX) use and randomized to receive CZP 400 mg (loading dose; according to CZP label) or placebo at weeks 0, 2, and 4. Pneumococcal (polysaccharide 23) and influenza vaccines were administered at Week 2. Satisfactory humoral immune response, defined as ≥2-fold titer increase in ≥3 of 6 pneumococcal antigens and ≥4-fold titer increase in ≥2 of 3 influenza antigens, were assessed independently 4 weeks after vaccination. RESULTS: Following pneumococcal vaccination, 62.5% of placebo patients and 54.5% of CZP patients without effective titers at baseline achieved a humoral response (difference in proportions was -8.0 percentage points; 95% CI -22.5 to 6.6%). Following influenza vaccination, 61.4% of placebo and 53.5% of CZP patients without effective titers at baseline achieved a humoral response (difference in proportions: -8.0 percentage points; 95% CI -22.9 to 7.0%). In all patients, including those with effective titers at baseline, 58.2% of placebo and 53.3% of CZP patients developed satisfactory pneumococcal titers, and 54.1% of placebo and 50.5% of CZP patients developed satisfactory influenza antibody titers. Vaccine responses to pneumococcal and influenza antigens were reduced similarly in both treatment groups with concomitant MTX use. CONCLUSION: Humoral immune responses to pneumococcal and influenza vaccination are not impaired when given during the loading phase of CZP treatment in patients with RA. (ClinicalTrials.gov NCT00993668).

Phase I dose escalation study to evaluate the safety and pharmacokinetic profile of tefibazumab in subjects with end-stage renal disease requiring hemodialysis.

Two cohorts of four subjects requiring hemodialysis received tefibazumab (10 or 20 mg/kg). The mean elimination half-life was between 17 and 18 days, the average volume of distribution was 7.3 liters, and the average clearance was 12 ml/h for both dose groups. At a dose of 20 mg/kg of body weight, plasma levels were 88 microg/ml at 21 days.

Phase II, randomized, double-blind, multicenter study comparing the safety and pharmacokinetics of tefibazumab to placebo for treatment of Staphylococcus aureus bacteremia.

Tefibazumab (Aurexis), a humanized monoclonal antibody that binds to the surface-expressed adhesion protein clumping factor A, is under development as adjunctive therapy for serious Staphylococcus aureus infections. Sixty patients with documented S. aureus bacteremia (SAB) were randomized and received either tefibazumab at 20 mg/kg of body weight as a single infusion or a placebo in addition to an antibiotic(s). The primary objective of the study was determining safety and pharmacokinetics. An additional objective was to assess activity by a composite clinical end point (CCE). Baseline characteristics were evenly matched between groups. Seventy percent of infections were healthcare associated, and 57% had an SAB-related complication at baseline. There were no differences between the treatment groups in overall adverse clinical events or alterations in laboratory values. Two patients developed serious adverse events that were at least possibly related to tefibazumab; one hypersensitivity reaction was considered definitely related. The tefibazumab plasma half-life was 18 days. Mean plasma levels were <100 microg/ml by day 14. A CCE occurred in six patients (four placebo and two tefibazumab patients) and included five deaths (four placebo and one tefibazumab patient). Progression in the severity of sepsis occurred in four placebo and no tefibazumab patients. Tefibazumab was well tolerated, with a safety profile similar to those of other monoclonal antibodies. Additional trials are warranted to address the dosing range and efficacy of tefibazumab.