About Stem Cell Transplant for MS

From the BEAT-MS Clinical Trial study description, annotations my own:

MS is a disease caused by one's own immune cells. Normally, immune cells fight infection. In MS, immune cells called T cells, or chemical products made by immune cells, react against the covering or coat (myelin) of nerve fibers in the brain and spinal cord. This leads to stripping the coat from certain nerve fibers (demyelination), and this causes neurologic problems. MS can cause loss of vision (thankfully temporary for me), weakness (my left arm and leg) or incoordination (yup, and balance problems), loss or changes in sensation (my feet think they are perpetually plunged into icy water, my left arm sends out weird SOS signals too), problems with thinking or memory (forget multitasking), problems controlling urination (I'll save those details for later), and other disabilities.

Most individuals with MS first have immune attacks (called relapses) followed by periods of stability. Over time, MS can have episodes of new and worsening symptoms, ranging from mild to disabling. This is called relapsing MS. Relapsing MS includes relapsing remitting MS (RRMS) and secondary progressive MS (SPMS). There are medicines (drugs) to decrease relapses, but these are neither considered to be curative nor, to induce prolonged remissions without continuing therapy.

More than a dozen medicines have been approved for the treatment of relapsing forms of MS. These medicines differ in how safe they are and how well they work. Despite availability of an increasing number of effective medicines, some individuals with relapsing MS do not respond to treatment (I tried a few drugs unsuccessfully before starting on ocrelizumab. It was amazing for me until Covid kicked my immune system back into high gear). Research is being conducted to find other treatments.

High dose immunosuppression followed by autologous hematopoietic stem cell transplantation (AHSCT) has been shown to help relapsing MS in cases where medicines did not work. AHSCT involves collecting stem cells, which are produced in the bone marrow. These stem cells are "mobilized" to leave the bone marrow and move into the blood where they can be collected and stored. Participants will then receive chemotherapy intended to kill immune cells. One's own stored (frozen) stem cells are then given back, through an infusion. This "transplant" of one's stem cells allows the body to form new immune cells in order to restore their immune system. New research suggest that MS might be better controlled with AHSCT than with medicines.

** With thanks to Carolyn of My Chronic Library for directing me to this infographic.