GenPharm International Inc. reported publicly for the firsttime that it generated human immunoglobulin gammaantibodies with affinity levels suitable for therapeutic use.
The privately held Mountain View, Calif., companypresented the milestone Tuesday at the InternationalConference of Antibody Engineering in La Jolla, Calif.The IgG antibodies were produced from GenPharm'sHuMAb-Mouse, a transgenic mouse line containinghuman antibody genes.
GenPharm scientists were able to cause the antibodies toundergo class switching and somatic mutation from low-affinity IgM antibodies to high-affinity IgG, atherapeutically useful class of antibodies. "Now that wecan make high-affinity antibodies, from a commercialpoint of view, is very impressive stuff," said JonathanMacQuitty, CEO of GenPharm.
"We've developed high-affinity human antibodies thatnow are suitable to take into the clinic," MacQuitty said."We're doing preclinical testing of those antibodies,characterizing them in various ways. We would like to bein the clinic around the end of 1996."
The company now can produce antibodies that bind to awide range of antigens, including human antigens,representing another step in the development process. Theintent now is to secure commercial partners that woulddevelop them against specific antigens.
GenPharm's first (and only) partner, Eisai Co. Ltd., inTokyo, is paying up to $25 million in a collaborationtargeting an undisclosed antigen. In separate newsTuesday, GenPharm said it renewed its 1993 research anddevelopment agreement with Eisai.
While specific terms were not revealed, MacQuittyoffered these details: GenPharm has received in theneighborhood of one-third of the potential $25 million;the changed terms provide more money in the near termand less down the road; and "as a result of this newarrangement GenPharm will be essentially cash-neutralnext year."
GenPharm has taken a few steps in the past year or so toreduce expenses. It sold its transgenic laboratory productsdivision to Taconic Farms Inc., of Germantown, N.Y., ina sale that included eight GenPharm transgenic animalmodels. GenPharm also spun off its European division inLeiden, the Netherlands. The company, now calledPharming B.V., was a wholly owned subsidiary and nowis an independent but affiliated company, MacQuitty said.
GenPharm's focus is on the human antibody-producingmouse. The HuMAb-Mouse contains key sequences fromunrearranged human antibody genes as well as havinginactivated mouse antibody genes. With the humansequences, the antibodies should avoid the rejectionproblems that affect mouse-based antibodies, thecompany said.
GenPharm said it already generated human IgGantibodies to antigens including IgE, CD4 and the cancerantigen CEA. n
-- Jim Shrine
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