P-MORF2

P-MORF2 is a synthetic, high-molecular-weight macromolecular conjugate designed as the crosslinking agent in a two-step pretargeted therapy known as "drug-free macromolecular therapeutics" (DFMT). This approach uses two engineered molecules administered sequentially: a targeting antibody fragment conjugated to MORF1 (Fab'-MORF1) and the effector P-MORF2, which contains multiple copies of a complementary morpholino oligonucleotide (MORF2) attached to a hydrophilic, non-immunogenic polymer backbone such as HPMA. When P-MORF2 is administered after Fab'-MORF1, it rapidly hybridizes with MORF1 on cell-surface bound Fab', inducing robust multivalent CD20 receptor crosslinking on malignant B cells. The resulting CD20 clustering triggers potent apoptosis without the need for a cytotoxic drug payload. This strategy is notable for its modularity, favorable pharmacokinetics, and reduced risk of off-target effects compared to traditional monoclonal antibody or antibody-drug conjugate therapies. Primary indications evaluated in preclinical models are B-cell malignancies, particularly non-Hodgkin lymphoma[1][9][13].