The Pharmacokinetics Of Turoctocog Alfa Are Consistent Over Different Concentrations and Production Lots

Turoctocog alfa is a B domain truncated human recombinant FVIII for treatment of patients with hemophilia A. The production yields a highly homogenous product with the same tyrosine sulphation as human FVIII. In order to confirm the consistency of turoctocog alfa pharmacokinetics (PK) over different production lots and vial strengths, a clinical trial was performed in 15 patients with severe hemophilia A.

To compare the PK of 3 lots of 2000 IU/vial and 1 lot of 3000 IU/vial of turoctocog alfa after i.v. administration of 50 IU/kg in patients with severe haemophilia A.

This was a multi-centre, open-label trial investigating the PK of 4 lots of turoctocog alfa (3 lots of 2000 IU/vial; Lots A, B and C, and 1 lot of 3000 IU/vial; Lot D) in patients with severe hemophilia A (FVIII<1%). The trial was performed as a two-period, incomplete block, cross-over trial, in which each patient was allocated at random to a predefined sequence of 2 different lots of turoctocog alfa.

The FVIII activity was assessed using both the one-stage clot and chromogenic assays. Both the primary endpoint, normalized AUC (AUC_*(planned dose/actual dose)), and the secondary PK endpoints were analyzed by ANCOVA on the log transformed values, with lot, visit and patient as fixed effects. Each of the three 2000 IU/vial lots was compared and tested against the 2 other 2000 IU/vial lots. If not significantly different on a 5% level, the 3 lots were pooled together and tested against the 3000 IU/vial lot.

Fifteen patients with a mean age of 38.6 years (ranging from 21 to 60 years) were included from 3 hemophilia centres in 3 different countries. Three adverse events (AEs) were reported in the trial by 2 separate patients; all AEs were judged to be unlikely related to the trial product. There was no development of inhibitors.

There was no pharmacokinetic difference observed between Lots A, B, C (2000 IU/vials) and there was no pharmacokinetic difference observed between the pooled data from lot A, B and C (2000 IU/vial) and lot D (3000 IU/vial) based on normalized AUC, half-life, incremental recovery and clearance. The estimated mean values (with 90% CI) for the PK parameters based on the chromogenic assay are presented in Table 1. The results were similar for the one-stage clot assay and the chromogenic assay.

No pharmacokinetic differences were observed between the three 2000 IU/vial lots (Lot A, Lot B and Lot C), nor were there pharmacokinetic differences between Lot D (3000 IU/vial) and pooled data from Lots A, B and C, based on normalized AUC, half-life, incremental recovery and clearance. There were no safety concerns and no inhibitor development in the trial.

Jiménez-Yuste:Novo Nordisk: Consultancy, Research Funding, Speakers Bureau. Klamroth:Novo Nordisk, CSL Behring, Bayer, Baxter, Pfizer: Honoraria, Research Funding. Saugstrup:Novo Nordisk: Employment. Moss:Novo Nordisk: Employment.