UK-based PolyTherics has developed a novel PEGylation technology, which involves coupling a polyethylene glycol (PEG) structure to a therapeutic protein, which acts to reduce the time it takes for the protein to leave the body.
PolyTherics is the latest company to announce a new technology platform. Last week, Virginia-based biopharmaceutical company Modigene announced it had developed new technology to increase the life span of proteins by attaching a carboxyl terminal peptide (CTP) to the protein.
Also last week, Merck-Serono announced it would be collaborating with US firm Ambrx on the development of a new long-acting growth hormone product, using Ambrx's ReCODE technology, which allows the precise positioning of a PEG polymer.
The market for long-lasting proteins is worth billions of dollars and pharmaceutical companies are looking for ways to protect already marketed proteins from proteolytic degradation and delaying kidney filtration.
PEGylated molecules increase the time that a substance remains in the bloodstream before being metabolised or excreted by the body.
The benefit of a long-lasting protein is it stays active in the body for longer thereby reducing the number of treatments the patient would need, which is normally three-plus a week with current marketed treatments.
While traditional PEGylation techniques can be problematic with decreased activity and increased toxicity, PolyTherics TheraPEG technology overcomes those problems, according to PolyTherics chief executive Keith Powell.
"With PEGylation there is always an effect on the activity of the protein but with ours we see less of an effect than with traditional techniques, and we can control it by controlling the molecular weight of the PEG," he told in-PharmaTechnologist.com.
Most traditional techniques involve amine PEGylation where the PEG is attached to free amines on the protein.
TheraPEG though, attaches the PEG to disulphides, which have fewer sites, producing a more pure product with a higher yield and a simpler process, Powell said.
Meanwhile, changing the half-life of the protein is as easy as changing the length of the PEG.
"Because you are always attaching at the same site, the half-life is always dependent on the length of the PEG so you don't have to re-optimise your whole process [to alter the half-life]."
Powell said the technology could be applied across all therapeutic proteins, including antibodies, enzymes and hormones.
The biopharmaceutical company is currently working with Shantha Biotech in India to make a long-lasting version of interferon-alph-2B, with clinical trials expected at the end of next year or early 2009.
There are also a number of collaborations with undisclosed pharmaceutical companies looking at increasing the half-life of antibody fragments.
PolyTherics received today £2.3m (€3.4m) collectively from supporters Imperial Innovations, Longbow Capital and The Capital Fund to help with further technological developments.
Founded in 2002, PolyTherics is a spin-out company from Imperial College London.
