Segments (Tables)

9 Months Ended

Sep. 30, 2025

Schedule of Segment Reporting Information, by Segment

Additional disaggregated significant segment expenses on a functional basis, that are not separately presented on the Company’s condensed consolidated statements of operations, are presented below:


	Three months ended September 30,				Nine months ended September 30,
	2025		2024		2025		2024
Personnel expenses excluding stock-based compensation	$	4,211	$	5,872	$	15,679	$	15,109
Stock-based compensation	2,189		1,998		6,162		6,065
Direct external program expenses:
ALTO-100	1,705		2,479		4,330		6,802
ALTO-300	1,396		1,990		2,971		4,647
ALTO-101	1,388		1,355		3,250		2,703
ALTO-203	218		1,057		1,554		2,542
ALTO-207	345		—		703		—
Other research and development (a)	1,147		913		6,326		5,476
General and administrative (b)	2,352		3,222		8,334		8,269
Loss from operations	$	14,951	$	18,886	$	49,309	$	51,613

(a) Other research and development expenses primarily consists of license fees, facility charges, third party consultant costs, early research costs related to other product candidates, and other unallocated costs.

(b) General and administrative costs include professional fees, insurance, consultant fees and facility charges.

Alto Neuroscience, Inc. 10-Q