Annual report [Section 13 and 15(d), not S-K Item 405]

Income Taxes - (Reconciliation of Income Tax) (Details)

v3.26.1
Income Taxes - (Reconciliation of Income Tax) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Reconciliation of income tax, Amount    
U.S. federal statutory tax rate $ (396)  
State and local income taxes, net of federal income tax effect $ 21  
Effective Income Tax Rate Reconciliation, State and Local Jurisdiction, Contribution Greater than 50 Percent, Tax Effect [Extensible Enumeration] mbio:NewYorkCityMember, stpr:MA, stpr:NY  
Change in valuation allowance $ (130)  
Non-deductible items:    
Share-based compensation 70  
Non-deductible compensation 170  
Stock issuance costs 83  
Other adjustments:    
Federal net operating loss 274  
Other true-ups (65)  
Provision for income taxes and effective income tax rate $ 27  
Tax Jurisdiction of Domicile [Extensible Enumeration] country:US  
Reconciliation of income tax, Percent    
U.S. federal statutory tax rate 21.00% 21.00%
State and local income taxes, net of federal income tax effect (1.10%) 16.00%
Change in valuation allowance 6.90% (27.00%)
Non-deductible items:    
Share-based compensation (3.70%)  
Non-deductible compensation (9.00%)  
Stock issuance costs (4.40%)  
Other adjustments:    
Federal net operating loss (14.50%)  
Other true-ups 3.50%  
Income taxes provision (benefit) (1.40%)