Technology

Protein Pharmaceuticals

Half life extension is a critical aspect of developing a successful protein pharmaceutical, as not all efficacious payloads have natural half lives that are amenable to reasonable dosing intervals or regimens.  

Current approaches to half life extension have met with modest success. Significant limitations of these approaches include complex conjugation or other similarly challenging manufacturing steps, heterogeneous product mixtures, increased cost of goods, renal tubular vacuolation, and injection site complications amongst others. Therefore, novel solutions are needed to address this important issue.

A Novel Half-life Extension Technology (XTEN)

XTEN is a proprietary recombinant polypeptide that, when genetically fused to a therapeutic payload of interest, extends the in vivo half-life of these peptides and proteins in a tunable manner.

The XTEN sequence consists of naturally-occurring hydrophilic amino acids and possesses a number of additional beneficial properties which are advantageous to the successful development of protein pharmaceuticals, including the following:

• XTEN sequences have been designed to be non-immunogenic and biodegradable
• XTEN fusion proteins are readily expressed as soluble, properly folded protein in E. coli, thus enabling efficient and economical manufacturing
• XTEN fusion proteins are stable at high protein concentrations and administered subcutaneously at small volumes with a small gauge needle 

Therefore, new compounds developed using the XTEN technology are expected to provide improved therapeutic outcomes such as enhanced efficacy, fewer side effects, better compliance/covenience (up to monthly dosing), as well as low-cost production and enhanced stability.