Lipoxen Technologies Incorporated

Peter Laing

Sanjay Jain

Gregory Gregoriadis

Ioannis Papaioannou

Norbert Oskar Rumpf

Dale Howard Hreczuk-Hirst

Andrew David Bacon

Wilson Romero Caparros-Wanderley

Gregory Gregoriados

Polydisperse and charged polysaccharides are fractionated into low polydispersity fractions (preferably having pd&#x3c;1.1), each containing species within a narrow range of molecular weights. An aqueous solution of the polydisperse polysaccharides is contacted with an ion exchange resin in a column and the polysaccharides are subjected to selective elution by aqueous elution buffer. The selective elution consists of at least 3 sequential elution buffers having different and constant ionic strength and/or pH and in which the subsequent buffers have ionic strength and/or pH than those of the preceding step. The new preparations are particularly suitable for the production of PSA-derivatised therapeutic agents intended for use in humans and animals.

Fractionation of charged polysaccharide

Derivatives are synthesized of starting materials, usually polysaccharides, having sialic acid at the reducing terminal end, in which the reducing terminal unit is transformed into an aldehyde group. Where the polysaccharide has a sialic acid unit at the non-reducing end it may be passivated, for instance by converting into hydroxyl-substituted moiety. The derivatives may be reacted with substrates, for instance containing amine or hydrazine groups, to form non-cross-linked polysialylated compounds. The substrates may, for instance, be therapeutically useful drugs peptides or proteins or drug delivery systems.

Sialic acid derivatives for protein derivatisation and conjugation

The present invention relates to process for reducing the endotoxin content of a sample of fermentation broth containing polysialic acid and endotoxin comprising the sequential steps: (i) adding to the sample a base having a pKa of at least 12 to form a basic solution having a pH of at least 12, incubating the solution for a pre-determined time at a pre-determined temperature; and (ii) recovery of PSA, suitably by (iii) passing the sample through an anion-exchange column whereby polysialic acid is absorbed on the ion exchange resin; (iv) washing the column with one washing buffer, whereby polysialic acid remains absorbed on the ion exchange resin; and (v) eluting the polysialic acid from the column using an elution buffer to provide a product solution of polysialic acid having reduced endotoxin content.

Reduction of endotoxin in polysialic acids

A polysialic acid compound is reacted with a hetero-bifunctional reagent to introduce a pendant functional group for site-specific conjugation to sulfhydryl groups, for instance side chains of cysteine units in drugs, drug delivery systems, proteins or peptides. The functional group is, for instance, an N-maleimide group.

Polysialic acid derivatives

Polydisperse and charged polysaccharides are fractionated into low polydispersity fractions (preferably having pd&#x3c;1.1), each containing species within a narrow range of molecular weights. An aqueous solution of the polydisperse polysaccharides is contacted with an ion exchange resin in a column and the polysaccharides are subjected to selective elution by aqueous elution buffer. The selective elution consists of at least 3 sequential elution buffers having different and constant ionic strength and/or pH and in which the subsequent buffers have ionic strength and/or pH than those of the preceding step. The new preparations are particularly suitable for the production of PSA-derivatized therapeutic agents intended for use in humans and animals.

The present invention relates to methods for producing N-terminal derivatives of proteins in which a polysaccharide, preferably having at least terminal sialic units, and preferably consisting essentially only of sialic acid units, is reacted at the N-terminus of a protein or peptide under controlled conditions to produce an N-terminal derivative. The controlled conditions include use of acidic pH for the derivatization step and a higher pH for purification. The derivatives are useful for improving pharmacokinetics and pharmacodynamics of proteins and peptides.

N-terminal derivatisation of proteins with polysaccharides

A liposomal composition, preferably a vaccine, comprising liposomes formed of liposome forming compounds, containing coentrapped polysaccharide antigen and T-cell dependent protein carrier, such as tetanus toxoid or diphtheria toxin modified to render it non-toxic. The invention is of use in the production of vaccines againstor

Liposomal vaccine compositions comprising a polysaccharide antigen and a protein adjuvant

The present invention relates to a compound which is a polysaccharide derivative of EPO, or of an EPO like protein, wherein the polysaccharide is anionic and comprises between 2 and 200 saccharide units. The present invention also relates to pharmaceutical compositions comprising the novel compounds, and methods for making the novel compounds.

Derivatisation of erythropoietin (EPO)

The present invention relates to a compound which is a polysaccharide derivative of GCSF, or of a GCSF like protein, wherein the polysaccharide is anionic and comprises between 2 and 200 saccharide units. The present invention also relates to pharmaceutical compositions comprising the novel compounds, and methods for making the novel compounds.

Derivatisation of granulocyte colony-stimulating factor

A composition comprising liposomes associated with a nucleic acid operatively encoding an antigenic protein and with an assistor protein, wherein the assistor protein shares at least one epitope with the antigenic protein, and wherein the nucleic acid and said assistor protein are associated with the same liposomes is described. The composition provides an improved immune response compared to mixtures of liposomes some of which are associated with the nucleic acid and some of which are associated with the assistor protein.

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London, United Kingdom

Peter Laing