Immunomedics has developed two new classes of bispecific antibodies, DOCK-AND-LOCK (DNL) complexes using its patented platform technology that enables site-specific conjugation of two self-assembling modules.
The bispecific antibodies have shown the cell killing activity against lymphoma cell lines in vitro.
The company, at the 2012 ASH Annual Meeting, has presented a new T-cell redirecting agent made as a DNL complex by connecting a pair of Fabs that recognize CD19 on B cells to a single-chain variable fragment (scFv) that binds to CD3 on T cells.
Called as (19)-3s, the prototype directs T cells to destroy CD19-expressing B cells by linking them together.
Immunomedics president and chief executive officer Cynthia Sullivan said, "We expect (19)-3s to have an elimination rate longer than that of blinatumomab, which is made of two scFvs to co-ligate CD19 and CD3."
The company has also presented an improved design of IgG-based DNL complexes that have the AD2-sequence fused at the end of the light chain in place of at the end of the heavy chain.
"The strategy of designing antibody fusion proteins at the C-terminus of the light chain, instead of at the commonly used Fc, may improve the in vivo efficacy of most immunoconjugates in general, and the DNL conjugates in particular," Sullivan added.
In addition, Immunomedics has presented results from a preclinical study of milatuzumab, a proprietary humanized anti-CD74 antibody.