Figure 1 - Key attributes of the albumin-fusion technology platform.

(a) Design flexibility. Albumin fusion technology permits the creation of recombinant, long-acting protein drugs by fusing the cDNA (gene X) encoding human albumin (HA) to cDNAs encoding therapeutically active proteins. Fusion can occur at either the N- or C-terminal of HA (arrows indicate transcription initiation). Molecular models depicting HA fusion to a large cytokine (IFN--2b) or a small peptide (glucagon-like peptide 1) illustrate the adaptability of the albumin fusion platform to biologically active compounds of varying sizes. (b) Reduced dosing frequency and sustained exposure. The observed therapeutic index of alb-IFN versus unmodified IFN is used as an example to illustrate the sustained exposure and reduced dosing frequency associated with the albumin-fusion technology platform. Unmodified IFN reaches peak levels shortly after administration, followed by a rapid decline to undetectable levels at the end of each dosing interval (TIW (three times weekly) dosing, on Monday, Wednesday and Friday). By contrast, alb-IFN administered Q2w (every two weeks) provides sustained drug exposure that lies within the range of therapeutic efficacy throughout each dosing interval. Sustained drug exposure accompanied by infrequent dosing might improve tolerability.