Tafasitamab is a recombinant, humanized Fc-engineered monoclonal antibody directed against the CD19 antigen. It is marketed in the United States as MONJUVI (tafasitamab-cxix) and in the European Union as MINJUVI. Tafasitamab is produced using recombinant DNA technology in Chinese hamster ovary (CHO) cells and has an approximate molecular weight of 150 kDa.
Tafasitamab is an oncology biologic designed to target CD19, a surface antigen expressed on pre-B and mature B lymphocytes and on several B-cell malignancies. Its Fc engineering enhances immune-effector functions, making it an important targeted biologic API for B-cell malignancy applications.
Unlike conventional small-molecule APIs, Tafasitamab is a complex recombinant protein. FDA's substance registry identifies Tafasitamab with UNII QQA9MLH692 and lists CAS 1422527-84-1 among its identifiers. The substance is also identified by development codes MOR-00208, MOR-208 and XMAB-5574.
Tafasitamab is an Fc-modified immunoglobulin G monoclonal antibody. Its biological characteristics depend on the recombinant production system, amino-acid sequence, disulfide structure, glycosylation profile and Fc engineering. Consequently, conventional small-molecule parameters such as melting point, residue on ignition and specific rotation are not normally suitable universal release criteria for this biological drug substance.
Tafasitamab binds to CD19, an antigen expressed on the surface of B lymphocytes and various B-cell malignancies. Following CD19 binding, tafasitamab promotes B-cell depletion through immune-mediated mechanisms including antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Direct induction of apoptosis also contributes to its biological activity.
The Fc region of tafasitamab has been engineered to enhance interactions with immune effector cells, resulting in increased immune-mediated activity compared with an unmodified antibody.
Tafasitamab is used in oncology, particularly for B-cell lymphomas.
In the United States, FDA originally approved tafasitamab-cxix in combination with lenalidomide for adults with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) who are not eligible for autologous stem-cell transplantation.
On June 18, 2025, FDA additionally approved tafasitamab-cxix in combination with lenalidomide and rituximab for adults with relapsed or refractory follicular lymphoma.
The European Medicines Agency lists Minjuvi for adult patients with relapsed or refractory DLBCL who are not eligible for autologous stem-cell transplantation, in combination with lenalidomide followed by tafasitamab monotherapy.
Tafasitamab is produced in mammalian CHO cells and has an approximate molecular weight of 150 kDa. The marketed drug product is supplied as a sterile, preservative-free, white to slightly yellowish lyophilized powder. FDA labeling states that reconstitution of a 200 mg vial with 5 mL sterile water produces a concentration of 40 mg/mL at approximately pH 6.0.
These finished-product characteristics should not be directly converted into API release specifications. For a monoclonal-antibody drug substance, attributes such as purity, aggregation, charge variants, glycosylation, potency and protein concentration are normally controlled using product-specific validated analytical methods.
Quality control of Tafasitamab drug substance should focus on biologically relevant critical quality attributes. Depending on the registered specification, testing may include:
Because Tafasitamab is a recombinant monoclonal antibody, conventional small-molecule tests such as loss on drying, residue on ignition, melting point and specific rotation are not appropriate universal API release tests.
Tafasitamab is manufactured through recombinant biotechnology using Chinese hamster ovary (CHO) cells. The manufacturing process involves cell culture, recovery and purification operations followed by appropriate viral safety and quality-control measures. FDA confirms that tafasitamab-cxix is produced using recombinant DNA technology in mammalian CHO cells.
For a biological API, manufacturing consistency depends on control of the cell substrate, culture process, purification process and critical quality attributes of the resulting antibody.
Tafasitamab drug substance should be stored and packaged according to validated stability data and the applicable registered biological-drug-substance specification.
The marketed MONJUVI product is supplied as a 200 mg single-dose vial of lyophilized powder. Following reconstitution, the resulting solution has a concentration of 40 mg/mL and pH 6.0.
Finished-product storage conditions should not be represented as the API drug-substance storage specification unless supported by the relevant drug-substance stability documentation.
A pharmaceutical-grade Tafasitamab API/drug-substance package may include a Certificate of Analysis, product specification, analytical methods, batch documentation, stability information, biological characterization data and regulatory documentation appropriate for the intended market.
A qualified Tafasitamab manufacturer in India should maintain strong biological manufacturing controls and validated analytical procedures for monoclonal-antibody identity, purity, potency and critical quality attributes. Particular attention should be given to control of aggregation, charge variants, glycosylation, host-cell impurities and biological activity.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |