REGN1908/1909 prevented cat allergen-induced early asthmatic responses in an environmental exposure unit.

BACKGROUND: The dominant allergen in cat dander, Felis domesticus allergen 1 (Fel d 1), is a persistent trigger for allergic rhinitis and asthma symptoms. OBJECTIVE: We evaluated the efficacy of Fel d 1 monoclonal antibodies (REGN1908/1909) in preventing cat allergen-induced early asthmatic responses (EARs) in cat-allergic patients with mild asthma. METHODS: Patients were randomized to single-dose REGN1908/1909 600 mg (n = 29) or placebo (n = 27). The FEV1 was measured for up to 4 hours in a cat allergen environmental exposure unit up to 85 days after dosing. Assessments included between-group differences in change from baseline in FEV1 area under the curve (AUC; 0-2 hours) and incidence of EAR (FEV1 reduction ≥20%). TRIAL REGISTRATION: NCT03838731. RESULTS: Single-dose REGN1908/1909 significantly prevented reductions in FEV1 on days 8, 29, 57, and 85. Most REGN1908/1909 patients did not have an EAR by 4 hours (the last time point tested). In contrast, placebo-treated patients experienced a ≥20% mean FEV1 reduction on days 8, 29, 57, and 85 after dosing, with most experiencing an EAR within 1 hour. REGN1908/1909-treated patients tolerated 3-fold higher allergen quantities (P < .05 at all time points) versus placebo. REGN1908/1909 substantially reduced skin test reactivity to cat allergen versus placebo at all time points tested (nominal P < .001). REGN1908/1909 was generally well tolerated; no serious adverse events or deaths were reported. CONCLUSION: Single-dose REGN1908/1909 significantly prevented reductions in FEV1 in cat-allergic patients with mild asthma on cat allergen environmental exposure unit exposure at 8 days and up to 85 days after dose.

Novel antibody cocktail targeting Bet v 1 rapidly and sustainably treats birch allergy symptoms in a phase 1 study.

BACKGROUND: The efficacy of an allergen-specific IgG cocktail to treat cat allergy suggests that allergen-specific IgG may be a major protective mechanism elicited by allergen immunotherapy. OBJECTIVES: Extending these findings, we tested a Bet v 1-specific antibody cocktail in birch-allergic subjects. METHODS: This was a phase 1, randomized, double-blind, study with 2 parts. Part A administered ascending doses of the Bet v 1-specific antibody cocktail REGN5713/14/15 (150-900 mg) in 32 healthy adults. Part B administered a single subcutaneous 900-mg dose or placebo in 64 birch-allergic subjects. Total nasal symptom score response to titrated birch extract nasal allergen challenge and skin prick test (SPT) with birch and alder allergen were assessed at screening and days 8, 29, 57, and 113 (SPT only); basophil activation tests (n = 26) were conducted. RESULTS: Single-dose REGN5713/14/15 significantly reduced total nasal symptom score following birch nasal allergen challenge relative to baseline. Differences in total nasal symptom score areas under the curve (0-1 hour) for subjects treated with REGN5713/14/15 versus those given placebo (day 8: -1.17, P = .001; day 29: -1.18, P = .001; day 57: -0.85, P = .024) and titration SPT with birch difference in area under the curve of mean wheal diameters for subjects treated with REGN5713/14/15 versus placebo (all P < .001) were sustained for ≥2 months; similar results were observed with alder SPT. REGN5713/14/15 was well tolerated. Basophil responsiveness to birch-related allergens was significantly decreased in subjects treated with REGN5713/14/15 versus those given placebo on days 8, 57, and 113 (all P < .01). CONCLUSIONS: Single-dose REGN5713/14/15 was well tolerated and provided a rapid (1 week) and durable (2 months) reduction in allergic symptoms after birch allergen nasal allergen challenge, potentially offering a new paradigm for the treatment of birch allergy symptoms.

Pharmacokinetic and Pharmacodynamic Analysis of Subcutaneous Tocilizumab in Patients With Rheumatoid Arthritis From 2 Randomized, Controlled Trials: SUMMACTA and BREVACTA.

Tocilizumab is a humanized anti-interleukin-6 receptor antibody for treating rheumatoid arthritis. Pharmacokinetic/pharmacodynamic analysis was performed on the 24-week double-blind parts of 2 randomized, controlled trials: SUMMACTA and BREVACTA. SUMMACTA compared subcutaneous tocilizumab 162 mg every week to intravenous tocilizumab 8 mg/kg every 4 weeks, whereas BREVACTA evaluated 162 mg subcutaneous tocilizumab every 2 weeks versus placebo. In addition to noncompartmental analysis, a 2-compartment population pharmacokinetic model, with first-order absorption (for subcutaneous) and linear and Michaelis-Menten elimination was used. Mean observed steady-state predose tocilizumab concentrations in week 24 were 40 and 7.4 µg/mL for subcutaneous every-week and every-2-week dosing, respectively, and 18 µg/mL for intravenous dosing. In the population PK model, body weight was an important covariate affecting clearance and volume of distribution. Mean ± SD population-predicted predose concentration for patients ≥100 kg was 23.0 ± 13.5 µg/mL for subcutaneous tocilizumab every week and 1.0 ± 1.6 µg/mL for every 2 weeks. Efficacy was lowest with subcutaneous every-2-week dosing in patients > 100 kg, reflecting lower exposure. The subcutaneous every-2-week regimen is not recommended for these patients. Pharmacodynamic responses were comparable for the every-week subcutaneous and every-4-week intravenous regimens and less pronounced with the every-2-week subcutaneous regimen. No trend was observed for increased adverse events with increasing tocilizumab exposure. The results of this analysis are consistent with the noninferiority of efficacy of the every-week subcutaneous regimen to the every-4-week intravenous regimen and the superiority of the every-2-week subcutaneous regimen to placebo. These results support the label recommendations for subcutaneous dosing of tocilizumab in rheumatoid arthritis patients.

Effect of renal impairment on multiple-dose pharmacokinetics of extended-release ranolazine.

Ranolazine is a novel compound under development as an antianginal agent. The multiple-dose pharmacokinetics of extended-release ranolazine and 3 major metabolites was investigated in healthy subjects (N = 8) and subjects with mild to severe renal impairment (N = 21). The ranolazine AUC(0-12) (area under the concentration-time curve between 0 and 12 hours after dosing) geometric mean ratio versus healthy subjects at steady state was 1.72 (90% confidence interval [CI], 1.07-2.76) in subjects with mild impairment, 1.80 (90% CI, 1.13-2.89) in those with moderate impairment, and 1.97 (90% CI, 1.23-3.16) in those with severe renal impairment. Creatinine clearance was negatively correlated with AUC(0-12) and the maximum observed concentration for ranolazine and the O-dearylated metabolite (P < .05 for all variables), as well as the N-dealkylated metabolite (P < .001), but not for the O-demethylated metabolite. Less than 7% of the administered dose was excreted unchanged in all groups, indicating that factors other than reduced glomerular filtration rate contributed to the increase in ranolazine concentrations in renal impairment. No serious adverse events were observed in the study.

Effect of hepatic impairment on the multiple-dose pharmacokinetics of ranolazine sustained-release tablets.

The effect of hepatic impairment on the pharmacokinetics of a sustained-release formulation of ranolazine and 3 major metabolites was investigated in an open-label, parallel-group study. Ranolazine (875-mg loading dose followed by 500 mg every 12 hours for a total of 4 maintenance doses) was administered to subjects with mild (n = 8) or moderate (n = 8) hepatic impairment and a matched control group of healthy volunteers (n = 16). Moderate, but not mild, hepatic impairment significantly increased ranolazine steady-state area under the concentration-time curve (AUC0-12) by 76% (P < .001) and maximum plasma concentration C(max) by 51% (P < .01). The AUC0-12 ratio (metabolite/ranolazine) decreased for all metabolites in parallel with the degree of hepatic impairment. AUC0-infinity for the CYP3A substrate midazolam administered as a single dose was significantly correlated with ranolazine AUC0-12 at steady state (r2 = .33, P < .001). Over the time interval studied, ranolazine was well tolerated in healthy subjects and hepatically impaired subjects.

Studies to investigate the pharmacokinetic interactions between ranolazine and ketoconazole, diltiazem, or simvastatin during combined administration in healthy subjects.

The interactions of ranolazine, a new antianginal compound, with inhibitors and substrates of the CYP3A isoenzyme family were studied in 1 open-label and 4 double-blind, randomized, multiple-dose studies. In healthy adult volunteers, the authors sought (1) to determine the steady-state pharmacokinetics, safety, and tolerability of immediate- and sustained-release ranolazine with and without ketoconazole, diltiazem, or simvastatin and (2) to evaluate the effect of ranolazine on the pharmacokinetics of diltiazem, simvastatin, simvastatin metabolites, and HMG-CoA reductase activity. Ketoconazole increased ranolazine plasma concentrations and reduced the CYP3A4-mediated metabolic transformation of ranolazine, confirming that CYP3A4 is the primary metabolic pathway for ranolazine. Diltiazem reduced oral clearance of ranolazine in a dose-dependent manner. Simvastatin did not affect ranolazine pharmacokinetics, although ranolazine increased the AUC and C(max) of simvastatin, simvastatin acid, 2 simvastatin metabolites, and HMG-CoA reductase activity by <2-fold. Administration of ranolazine in combination with diltiazem or simvastatin was safe and well tolerated during the interval studied.