New Myeloma Acronym of the Day: msAb

BY PAUL KLEUTGHEN As multiple myeloma patients, we've all had to learn a whole new vocabulary relating to our disease. More importantly, we need to continually absorb new acronyms to stay abreast of advances in therapeutic technologies. Today’s new acronym is msAb, short for bi- and multi-specific antibody. An interesting article was published in “Genetic Engineering & Biotechnology News” titled “Bispecific Antibodies reemerge” authored by Patricia Fitzpatrick Dimond Ph.D.  Much has been written recently about CAR-T cell technologies and their treatment potential in a variety of cancers, especially blood cancers, including myeloma. CAR-T cell treatment directs genetically engineered T-cell receptors to a specific tumor antigen, or protein on the surface of the myeloma cells. In the case of msAb’s the “modified antibodies engage two different targets simultaneously”.  The first msAb in the US, Blincyto (blinatumomab), was approved by US FDA on December 3^rd for the treatment of a rare form of B-cell acute lymphoblastic leukemia (ALL). Another msAb (Removab) has been approved in Europe since 2009 for the treatment of malignant ascites, a condition occurring in patients with metastizing cancer. This product is currently in clinical trials in the US. The article provides a nice summary of how CAR-T cell and msAb technologies differ. Unlike CAR-T technology, where cells are custom engineered on a patient-by-basis, msAb’s treat “all” patients for a given disease class which should drive down the long-term cost of treatment for a given patient (compared to CAR-T treatment). This is a more off-the-shelf approach. CAR-T technology is also more advanced, at this stage, compared to msAb’s but it will only be a matter of time before research in this area will expand. The article notes that both CAR-T and msAb treatments show  the same or similar toxicities but at the same time states that:

“Despite the fact that bsAbs can produce a similar array of life-threatening side-effects as CAR T-cell therapies, Dr. van de Winkel said he believes bsAbs will drive 60% of the growth in the therapeutic antibody field in the coming years, and might provide a safer and more druggable “analog” to CAR T-cell technology.”