BioWorld International Correspondent

Shares in Intercell AG rose to an all-time high Tuesday during trading on the Vienna Stock Exchange on news that the company licensed its IC31 vaccine adjuvant to Wyeth, in a nonexclusive deal worth up to $77 million in up-front, option and milestone payments. Intercell would also gain royalties on product sales.

In return, Madison, N.J.-based Wyeth obtained rights to use IC31 to develop vaccines against five undisclosed infectious disease pathogens.

"It's nonexclusive because we felt adjuvants should be open to partnering at all levels and for all targets," Alexander von Gabain, chief scientific officer and co-founder of Vienna, Austria-based Intercell, told BioWorld International. "We could certainly have gotten a better up-front payment if we had gone into exclusive mode."

IC31 contains two components, an immunostimulatory oligodeoxynucleotide (ODN1a) and an antimicrobial peptide (KLK). It stimulates the innate immune system and ultimately both arms of the adaptive immune response via the Toll-like receptor-9 (TLR-9)/MyD88 signaling pathway.

ODN1a is an agonist for TLR-9, which identifies specific CpG-containing DNA motifs that are characteristic of microbial and viral pathogens. The oligonucleotide is taken up by dendritic cells in the skin, which then trigger an immunological cascade. KLK, a cationic anti-bacterial peptide, acts as a "gating molecule," von Gabain said. It helps to protect ODN1a against degradation, and it also assists the transport of foreign antigens into dendritic cells. When used alone, it helps to elicit a Th2 or antibody-mediated immune response, von Gabain said.

Intercell previously entered shared-cost development programs involving IC31, but up to now had not signed a cash-bearing deal with one of the vaccine industry's dominant players. Intercell and the Statens Serum Institut (SSI), of Copenhagen, Denmark, joined forces in 2004 on the development of a novel tuberculosis subunit vaccine based on IC31 and an antigen identified by the SSI.

That program subsequently received funding from the Bethesda, Md.-based Aeras Global TB Vaccine Foundation, which is supported by the Bill and Melinda Gates Foundation, of Seattle. The vaccine is undergoing a Phase I trial, the results of which will be available before the year's end, von Gabain said. A joint program with Singapore-based SciGen Ltd. on the development of an IC31-adjuvanted vaccine against hepatitis B virus still is in preclinical development.

Intercell's share priced climbed as high as €15.15 (US$19.22) during trading Tuesday, up more than 70 percent since the beginning of the year.