Interpretation of my country's first stem cell drug

Recently (January 2, 2025), the National Medical Products Administration, through the priority review and approval procedure, conditionally approved the listing of China's first stem cell therapy drug "Amimaxetal Injection" ! This drug will be used as a prescription drug to treat acute graft versus host disease (aGVHD) in patients aged 14 and above who have failed hormone therapy with gastrointestinal involvement, bringing new hope to many patients. So, what are stem cells? What kind of stem cells does this drug contain?

01 What are stem cells

Stem cells are cells that have the potential for self-renewal and multidirectional differentiation (Figure 1). In layman's terms, cells that can enter the stem cell family must have two major skills: " replication " skills (one becomes two, two becomes four...); " transformation " skills (become other types of cells). According to the "transformation" ability from strong to weak, stem cells can be divided into totipotent stem cells, pluripotent stem cells and multipotent stem cells.

【Figure 1. Basic characteristics of stem cells】

02 The active ingredient of “Amytometosyl Injection” – mesenchymal stem cells

The active ingredient of "Amytometosyl Injection" is mesenchymal stem cells derived from human umbilical cord tissue , which we commonly call MSC.

The replication and deformation ability of MSC is at a medium level in the stem cell family, and it is relatively safe and more controllable. In the body, MSC can differentiate into specific cell types, such as bone cells or chondrocytes, to replace and repair damaged tissues, and can also promote the body's self-repair by regulating the immune system and tissue microenvironment. It is precisely because of these characteristics that MSC has become the most favored type of stem cell in clinical research. In addition to being obtained from umbilical cord tissue, MSC can also be obtained from a variety of human tissues such as bone marrow, fat, and placenta . After in vitro amplification and identification, they are then infused back into the body for disease treatment (Figure 2).

【Figure 2. Acquisition, identification and clinical treatment of MSC】

However, it should be noted that MSCs obtained from different donor sources, tissue sources, and culture conditions have both similarities and differences in morphology and function. Even a group of MSCs obtained through the same route may have differences, which we also call " heterogeneous " cells. In order to provide a relatively unified definition of MSCs, the International Society for Cellular Therapy (ISCT) established three minimum standards for identifying human MSCs in 2006:

(1) It can grow by plastic adhesion;

(2) Most cells express protein molecules CD105, CD73, and CD90 on their surface, but do not express protein molecules such as CD45, CD34, CD14, CD11b, CD79a, CD19, and HLA-DR;

(3) Cells can differentiate into osteoblasts, adipocytes, and chondrocytes when cultured in vitro.

Because of the heterogeneity of MSC, any mesenchymal stem cell product must undergo strict testing and monitoring of its source, acquisition method, culture method, and cell properties. At the same time, its indications must be repeatedly verified to ensure the safety and effectiveness of the treatment before it can be truly applied in clinical practice.

03 Stem cells are not a panacea

Stem cells are a general term that includes different types of cells. Today we focus on mesenchymal stem cells, which are also the main type of stem cell products currently on the market. In the future, we will continue to introduce other types of stem cells to you.

It should be noted that no matter what kind of stem cell, it is by no means a "panacea". There are differences in the production process and cell population obtained for different stem cell products. The corresponding indications of each product are also different. They cannot be mixed casually, let alone blindly believe in various unscientific stem cell therapies without professional guidance! The "Amymetosel Injection" stem cell preparation listed in my country is mainly used to treat specific rejection reactions after hematopoietic stem cell transplantation. This type of disease is relatively rare. As for stem cell treatment for other diseases, it is still necessary to participate in clinical trials in my country. For specific content, you can look back at our previous tweet "Hotspot | Is online pyramid selling targeting stem cells? Bringing you closer to formal stem cell treatment."