Unapproved regenerative medicine for spinal cord injury in Japan.

This study presented an overview of unapproved regenerative medicine for spinal cord injury (SCI) in Japan under the Act on the Safety of Regenerative Medicine. In total, 41 non-research regenerative medicine provision plans were identified. Three plans (7%) specified administration exclusively during the chronic phase, whereas remaining plans did not state the period. Most therapies used adipose-derived (68%) or bone marrow-derived (32%) mesenchymal stem cells. The most common administration route was intravenous (71%), followed by intrathecal (27%). Culture periods were typically around four weeks, and the most frequently administered cell dose was 1.0 × 108 cells, although variability existed across plans. The mean treatment price was 14,100 USD. Clinical research conducted under the RM Act and approved regenerative medical products primarily targeted subacute SCI, using standardized cell sources, dosing strategies, and safety evaluations. These findings demonstrate marked heterogeneity and limited scientific standardization among unapproved regenerative medicine for SCI in Japan.