to block the formation of a certain sugar called fucose that often hangs off the end of a regular antibody. By getting rid of that type of sugar, scientists think they can trigger the immune system to unleash a more powerful assault on the cells that the antibodies bind with, Siegall says.
Since this approach can make antibodies more potent without using a toxin, it’s possible that sugar-engineered antibodies might be better tolerated for long-term usage. That could be useful for diseases in which the antibody needs to be given for a chronic disease, like rheumatoid arthritis, Siegall says.
At least two other companies appear to be further along than Seattle Genetics with this sort of sugar-based approach for empowering antibodies, Siegall says. One is BioWa, a unit of Japan-based Kyowa Hakko Kirin, and the other is GlycArt, now a unit of Roche. The GlycArt technology is being used for a drug candidate called GA-101, an empowered version of Roche and Biogen Idec’s hit rituximab (Rituxan). But Siegall says the Seattle Genetics approach should have an advantage because it only adds one chemical step to the antibody production process, and doesn’t slow things down like the others can.
Like Seattle Genetics’ earlier experience with antibody-drug conjugates, it hopes to use the sugar-engineered antibody approach both for internal programs, and for licensing to other companies, Siegall says. “We are talking to a number of companies about it, and there is interest,” he says.
Since that technology is still relatively new, Siegall tried not to pump up expectations too high about it becoming a moneymaker for the company anytime soon. But it’s a clear indicator that Seattle Genetics is looking at a number of ways to build upon the successes of the plain antibodies from the past.
“These products have been around for a while and they help patients,” Siegall says. “Now we have an opportunity to take antibodies to the next level. The data speaks louder than anything else, and the data are strong.”
