Suppression of Rituximab-resistant B-cell lymphoma with a novel multi-component anti-CD20 mAb nanocluster

The novel fourth generation multifunctional nano based mAbs was developed by Prof. Wei Li’s group from International Joint Cancer Institute, the Second Military Medical University  

Since the first generation monoclonal antibodies (mAbs) like anti-CD20 (rituximab) was approved by Food and Drug Administration (FDA) in 1997, more than ten mAbs have been used for cancer therapy. For further boosting mAbs’ cellular cytotoxicity, the second generation mAb drug conjugates (ADC) was developed subsequently. It is known that simultaneous blocking multiple mediators by the third generation mAbs offers new hope for complex diseases treatment. But the curative potential of current combination therapy by chronological administration of separate mAbs or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. In addition, a lot of patients does not respond to mAbs and/or acquires resistance on long-term therapy.

Here, Dr. Wei Li from the International Joint Cancer Institute, the Second Military Medical University reports a facile strategy that armies distinct mAbs with cooperative effectors onto a long polymer chain to form a new multicomponent comb-like nano based mAb. Prof. Li said, “This should be the fourth generation of novel multifunctional mAbs”. In their experiments, the multifunctional nano based mAb, which was finely constructed from two distinct type I/II anti-CD20 mAbs (Rituximab and 11B8), shows good pharmacokinetics. The nano antibody can simultaneously binding with distinct epitopes on single CD20 antigen (Ag) and neighboring Ags on different lymphocytes. Such unique intra-/inter-cellular Ag’s crosslinking endows the nano mAb with potent apoptosis inducing ability. The potent effectors are further synergistically promoted via the enhanced permeability and retention (EPR) as shown in following Figure. Importantly, such nano based antibody formulation efficiently inhibited Rituximab-resistant lymphomas in both disseminated and localized human NHL xenograft models. Compared with its parental single molecular mAbs, this novel nano mAb’s modulates showed exceptionally potential for cancer therapy. Prof. Li said: “In the future, the cancer may be cured but not suppressed by such novel fourth generation multifunctional mAbs. We do hope the facile strategy could really revolutionize the treatment of many human malignancies.” They have applied related patents for intellectual property protection.