2017: Salubris Biotherapuetics: Bispecific, Biparatopic Antibody-Drug Conjugate for Human Liver Cancers

Attached are the August 8, 2017 KEI comments regarding the prospective grant of an exclusive patent license by the NIH to Salubris Bioterapuetics for the development of a bispecific, biparatopic antibody-drug conjugate to GPC3 for the Treatment of Human Liver Cancers. (Copy here).

The notice was published in the Federal Register on August 7, 2017. (Document Citation:, 82 FR 36808)

The KEI comments include seven requests for information about the license and several suggestions for terms that could be included in the license to protect US residents from high prices and/or discriminatory prices, and to provide more transparency regarding the economics of the development and commercialization of the technology.

The key shareholder in Salubris Bioterapuetics is Ye Chenghai, the Chinese billionaire former mayor of Shenzhen.

KEI offered the following observations on the potential medical benefits of the technology.

Therapeutic antibodies have revolutionized therapy for cancer and autoimmune diseases. First monoclonal antibodies were used to target a single epitope on malignant cells, or harmful protein. Antibodies were then rendered more potent by conjugating cytotoxic molecules to them. As our understanding of the immune system is improving, we can now use antibodies to activate our lymphocytes against tumor cells. Breakthroughs in recombinant DNA technology and sequencing have enabled scientists to design multispecific antibodies that can target more than one epitope on the same or different antigen. This new generation of antibodies are effectively multi-tools with each Fv performing a different function. For example, bispecific antibodies can on one hand bind to receptors overexpressed on tumor cells and also increase internalization (for drug delivery) or trigger cell death. Some bispecific antibodies, such as BiTEs, can link effector T-cells to cancer cells. The considered license describes two paratopes that could be engineered within one antibody to target liver cancer cells. Not only would this improve the specificity of the antibody drug conjugate, but it could also inhibit growth in these cancer cells. Many bispecific antibodies are already in clinical trials and several are already on the market. The versatility of these next generation antibodies makes them highly effective therapeutic agents.

Salubris-8Aug2017.pdf102.92 KB