CONDENSED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 54,124	$ 75,289
Marketable securities	364,457	298,416
Prepaid expenses and other current assets	9,281	7,834
Total current assets	427,862	381,539
Property and equipment, net	4,663	2,735
Right-of-use assets	2,759	487
Other assets	625	383
Total assets	435,909	385,144
Current liabilities:
Accounts payable	4,356	2,977
Accrued expenses	18,673	12,346
Operating lease liabilities, current	631	172
Total current liabilities	23,660	15,495
Share repurchase liability	0	2
Operating lease liabilities, net of current	2,710	424
Total liabilities	26,370	15,921
Commitments and contingencies (Note 9)
Stockholders' equity
Undesignated preferred stock, $0.0001 par value, 10,000,000 shares authorized and zero issued and outstanding as of June 30, 2026 and December 31, 2025	0	0
Common stock, $0.0001 par value, 500,000,000 shares authorized and 47,949,804 issued and outstanding as of June 30, 2026 and 500,000,000 shares authorized and 44,927,953 issued and outstanding as of December 31, 2025	6	6
Additional paid-in-capital	695,843	593,407
Accumulated deficit	(285,088)	(224,476)
Accumulated other comprehensive (loss) income	(1,222)	286
Total stockholders' equity	409,539	369,223
Total liabilities and stockholders' equity	$ 435,909	$ 385,144

Share repurchase liability.

No definition available.

Name:	mbx_ShareRepurchaseLiability
Namespace Prefix:	mbx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).