identify differences in response in all key endpoints [PASI 75, PASI 100, sPGA success (0 or 1), and sPGA clear (0)] to Kyntheum among these subgroups.
Along with primary efficacy endpoints, clinically important improvements were observed in Psoriasis Scalp Severity Index (PSSI) at Week 12 (AMAGINE-1) and in Nail Psoriasis Severity Index (NAPSI) at Week 12 and 52 (AMAGINE-1,-2, and -3).
Quality of life/patient reported outcomes
The proportion of patients who achieved a Psoriasis Symptom Inventory (PSI) score of 0 (not at all) or 1 (mild) on every item (itch, burning, stinging, pain, redness, scaling, cracking and flaking) at Week 12 are shown in Table 2.
The percentage of patients that at Week 12 achieved a DLQI (Dermatology Life Quality Index) score of 0 or 1 was 56%, 61%, 59% in the Kyntheum 210 mg group and 5%, 5%, 7% in the placebo group in AMAGINE-1, -2 and -3, respectively (adjusted p-value <0.001) and 44% in the ustekinumab groups (AMAGINE-2 and -3).
Paediatric population
The European Medicines Agency has deferred the obligation to submit the results of trials with Kyntheum in plaque psoriasis in one or more subsets of the paediatric population (see section 4.2 for information on paediatric use).
5.2 Pharmacokinetic properties
Absorption
Based on population pharmacokinetic modelling, the estimated accumulation ratio after 20 weeks of dosing is 2.5-fold. In moderate to severe plaque psoriasis patients following a single subcutaneous administration of Kyntheum at 210 mg, the mean maximum serum concentration (Cmax) was 13.4 mcg/ml (standard deviation [SD] = 7.29 mcg/ml). The median time to maximum concentration (Tmax) was 3.0 days (range: 2.0 to 4.0 days) and the mean area under the concentration time curve to the last measurable concentration (AUClast) was 111 mcg*day/ml (SD = 64.4 mcg*day/ml). The subcutaneous bioavailability of brodalumab estimated by population pharmacokinetic modelling was 54.7% (relative standard error [RSE] = 4.25%).
The observed pharmacokinetic parameters during steady-state (weeks 10-12) were: mean steady-state area under the concentration time curve over the dosing interval (AUCtau) was 227.4 mcg*day/ml (SD = 191.7 mcg*day/ml) corresponding to average concentration (Cav,ss) of 16.2 mcg/ml, mean Cmax was 20.9 mcg/ml (SD = 17.0 mcg/ml) and Week 12 mean minimum serum concentration (Ctrough) was 9.8 mcg/ml (SD = 11.2 mcg/ml).
Distribution
Based on population pharmacokinetic modelling, the estimated mean steady-state volume of distribution of brodalumab was approximately 7.24 L.
Biotransformation
As an IgG2 human monoclonal antibody brodalumab is expected to be degraded into small peptides and amino acids via catabolic pathways in a manner similar to endogenous IgG.
Elimination
Following subcutaneous administrations of 210 mg, brodalumab exhibits non-linear pharmacokinetics typical for a monoclonal antibody that undergoes target-mediated drug disposition.
Brodalumab clearance decreases with increasing dose and exposure increases in a greater than dose-proportional manner. For a 3-fold increase in SC brodalumab dose from 70 to 210 mg, the steady-state serum brodalumab Cmax and AUC0-t increased approximately 18- and 25-fold, respectively.
Following a single subcutaneous administration of brodalumab 210 mg in plaque psoriasis patients, the apparent clearance (CL/F) is 2.95 L/day.
Population pharmacokinetic modelling predicted that serum brodalumab concentrations dropped below the qu |
