Nature of the Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Nov. 07, 2022	Sep. 21, 2022	Mar. 11, 2021
Nature Of Business And Basis Of Presentation [Line Items]
Entity incorporation month and year	2013-12
State of incorporation	DE
Net loss	$ (46,415)	$ (89,756)
Accumulated deficit	413,878	367,463
Milestone payment	225,000
Common stock to be issued	$ 52	$ 32
Spero Therapeutics LLC [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Merger date	Jun. 30, 2017
GSK License Agreement [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Common stock to be issued				$ 9,000
GSK License Agreement [Member] | Glaxo Smith Kline [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Milestone payment			$ 66,000
At-The-Market Offering Program [Member] | Cantor Fitzgerald & Co [Member] | Maximum [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Authorized offering value					$ 300,000
Common stock available for issuance					$ 75,000