Biosimilars for Cancer Treatment

Patients, insurance companies, and doctors generally like it when generic forms of medicines become available as they are less expensive than the brand name.  And small molecule drugs can be made as generics once the patent expires.  For biologics (which includes monoclonal antibodies and vaccines) it is not so straightforward.  Even after the patent expires, these are difficult to make because in general they are difficult to make.  The originator has not just the patent as protection but also the trade secret.

Enter “biosimilars”.  These are not exact copies of the original medicine, but they act in the same manner in the body.  Regulatory agencies will approve medicines that have been shown to have the same efficacy in the body.  Like generics, biosimilars tend to be less expensive than the original medicine, but still not inexpensive.

The seller can use any brand name they choose, but the generic or scientific name is dictated by the regulatory agency.  The name for biosimilars is the same as the name of the source biologic product but appended with four letters.  These four letters have no special meaning, but are just meant to differentiate among the biosimilars and to indicate the original drug the biologic is duplicating.

As of early 2021, the US FDA has approved 29 biosimilar drugs.  While most are for arthritis treatment, some are approved for cancer therapy:


Original Biosimilar Brand Name Manufacturer
bevacizumab bevacizumab-awwb Mvasi Amgen
bevacizumab bevacizumab-bvzr Zirabev Pfizer
rituximab rituximab-abbs Truxima Celltrion
rituximab rituximab-pvvr Ruxience Pfizer
rituximab rituximab-arrx Riabni Amgen
trastuzumab trastuzumab-dkst Ogivri Mylan
trastuzumab trastuzumab-pkrb Herzuma Celltrion
trastuzumab trastuzumab-dttb Ontruzant Samsung Bioepis
trastuzumab trastuzumab-qyyp Trazimera Pfizer
trastuzumab trastuzumab-anns Kanjinti Amgen