|
Highly Reactive and hydrophobic PEG derivatives
for conjugating to therapeutic proteins
First generation PEGs, SS-PEG and SC-PEG, generally
possess disadvantages of
1) weak linkages between PEG and protein, 2) side reactions,
3) inability to remove major contaminants and 4) restriction
to low MW PEGs. Further, branched PEG conjugates showed
much slower clearance rate in blood than linear PEGs
indicating that branched one acts much larger than linear
one. However, the reactivity of
branched PEGs to proteins are low due to steric hindrance.
Our biological PEG derivatives have more hydrophobic-hydrophilic
balance property and umbrella like structure resulting
in enhanced reactivity and efficacy in vivo.
PEG copolymers with enhancing cell trafficking
Typical PEG conjugation to small molecules, such as
Paclitaxel and Campthothecin, showed the enhancing solubility.However,
these PEG-drugs are inefficient to deliver the hydrophobic
drugs into the cell membranes due to attachment of hydrophilic
polymers. Our PEG copolymers comprising a hydrophilic
segment to allow the stable and long circulating drug
and a positive charged segment to allow high cellular
uptake of drugs and to enhance the intracellular trafficking
for effective drug delivery. PEG copolymer can be also
applicable as effective gene deliver system.
Site-specific PEGylation of therapeutic proteins
and peptides
BPM has expertise in the methods by which PEG can be
attached to potein or peptides and the selection of
appropriate sites on the compound to which PEG is attached.
The site and numbers of PEG attached to proteins and
peptides are one of key factors to develop PEG-drugs
successfully.
Ex) interferon, G-CSF, EPO, hGH, IL-2, PTH, calcitonin,SCA,
etc.
Hepatocyte targeting PEGylated drugs
BPM is also developing PEG derivatives to target delivery
of drugs to hepatocytes.
With Not only targeting property but also long circulating
half-life, The use of these PEG derivatives would reduce
the dose of drugs administered resulting in enhancing
the efficacy of drugs and lowering toxicity of drugs.
Ex) Antibiotics, Anticancer agents
|
