BsMAbs can be separated into two main categories based on structure. Fc-based BsMAbs are similar to normal mAbs, with an Fc region and two Fab regions. However, the Fab regions of BsMAbs are structurally different, allowing the antibody to bind two distinct types of antigen.

Fragment-based BsMAb lacks the Fc region. They are formed from two or more distinct antibody fragments attached to a peptide linker. This makes it much smaller than Fs-based BsMAb, which makes it easier to penetrate into the network. To get more information about antibodies, you can also visit

Image Source: Google

Fragment-based BsMAbs

While Fc-based BsMAb allows antibodies to bind to two antigens while immune cells bind and initiate an immune response, fragment-based BsMAb often act similarly to mAbs, but with a smaller size.

One antibody fragment binds to an antigen on a foreign or damaged cell, while the other triggers an immune response.

The small size of fragment-based BsMAbs reduces the distance between target cells and effector cells. This can allow target cells to be killed more efficiently than normal mAbs.

The smaller size also results in a shorter half-life and faster release from the body. This can be useful for some drugs where antibodies can have a significant toxic effect, such as some cancer drugs.

For example, BsMAb blinatumomab binds to CD3ε T cells and CD19 B cells, causing B cells to be killed. CD19 is most commonly expressed in malignant B cells in leukemia and lymphoma, so this antibody is an effective anti-cancer drug.