Alpha-C-GalCer as a potential therapeutic vaccine adjuvant

Only a few molecules have been shown to activate NKT cells. Of these, alpha-galactosylceramide (alpha-GalCer), aglycolipid originally derived from a marine sponge extract, is the best characterized. A new generation of iNKT ligands was produced and screened allowing to select CYT209 as the most potent and specific molecule to induce a secondary release of Th-1 type cytokines such as IFNg and IL-12.

In their paper (1), Schmieg et al. suggest that “if NKT cell–directed therapy ever comes to fruition in humans, alpha-C-GalCer’s Th1-enhancing activity makes it an excellent chemotherapeutic candidate for a number of human diseases, including cancer metastases, allergy, and various infectious diseases such as hepatitis B and C (2). Given the fact that recent clinical trials have shown that alpha-GalCer appears to have biological activity in cancer patients (3, 4), alpha-C-GalCer has promise as a therapeutic agent.”

This product candidate (CYT209) is currently in preclinical development (GMP synthesis and regulatory testing) with the aim of testing its vaccine adjuvant potential in a phase I “proof of concept study” in patients in 1H 2009.

References Cited

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