Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 64,988	$ 15,858
Short-term investments	327,978	82,478
Prepaid expenses and other current assets	7,558	6,913
Restricted cash, current portion	211	37
Total current assets	400,735	105,286
Long-term investments	69,812	0
Property and equipment, net	198	460
Goodwill	10,502	10,502
Restricted cash, net of current portion	183	210
Total assets	481,430	116,458
Current liabilities:
Accounts payable	2,458	137
Accrued expenses and other current liabilities	21,636	12,803
Total current liabilities	24,094	12,940
Royalty obligation	2,000	2,000
Deferred tax liability, net	470	434
Derivative liability, non-current	18,320	18,000
Other long-term liabilities	0	35
Total liabilities	44,884	33,409
Mezzanine equity:
Temporary equity, values issued	0	0
Stockholders’ equity:
Common stock—$0.001 par value; 200,000,000 shares authorized at September 30, 2026 and December 31, 2025; 53,923,083 and 18,512,757 shares issued and outstanding at September 30, 2026 and December 31, 2025, respectively	54	18
Additional paid-in capital	961,459	531,485
Accumulated other comprehensive (loss) income	(1,512)	68
Accumulated deficit	(523,455)	(448,522)
Total stockholders’ equity	436,546	83,049
Total liabilities, mezzanine equity and stockholders’ equity	481,430	116,458
Series D Preferred Stock
Mezzanine equity:
Temporary equity, values issued	0	0
Series E Preferred Stock
Mezzanine equity:
Temporary equity, values issued	0	0
Series C preferred stock
Stockholders’ equity:
Series C Preferred Stock—$0.001 par value; 3,359 and 34,326 shares of Series C Preferred Stock authorized at September 30, 2026 and December 31, 2025, respectively; 3,359 and 18,792 shares of Series C Preferred Stock issued and outstanding at September 30, 2026 and December 31, 2025, respectively	0	0
Series C-1 preferred Stock
Stockholders’ equity:
Series C Preferred Stock—$0.001 par value; 3,359 and 34,326 shares of Series C Preferred Stock authorized at September 30, 2026 and December 31, 2025, respectively; 3,359 and 18,792 shares of Series C Preferred Stock issued and outstanding at September 30, 2026 and December 31, 2025, respectively	$ 0	$ 0

Property, Plant and Equipment and Operating Lease Right-of-use Asset, After Accumulated Depreciation and Amortization

No definition available.

Name:	avtx_PropertyPlantAndEquipmentAndOperatingLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization
Namespace Prefix:	avtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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).