Funding Arrangement - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Funding Arrangement [Line Items]
Grant income				$ 329,000
Cost Reimbursement Sub-Award Agreement
Funding Arrangement [Line Items]
Funding period of award to develop universal vaccine to prevent infections caused by Group A Strep bacteria		4 years
Percentage of reimbursable expenses		50.00%
Grant income			$ 0	$ 300,000
Cost Reimbursement Sub-Award Agreement | Maximum
Funding Arrangement [Line Items]
Initial funding committed by award		$ 1,600,000
Total funding committed by award, available upon achievement of development milestones		$ 15,100,000
CARB-X Agreement
Funding Arrangement [Line Items]
Funding period of award to develop universal vaccine to prevent infections caused by Group A Strep bacteria	4 years
Grant receivable on unreimbursed, eligible costs incurred			$ 0		$ 300,000
CARB-X Agreement | Maximum
Funding Arrangement [Line Items]
Percentage of reimbursable expenses	90.00%
Initial funding committed by award	$ 2,700,000
Total funding committed by award, available upon achievement of development milestones	$ 15,100,000
CARB-X Agreement | Minimum
Funding Arrangement [Line Items]
Percentage of reimbursable expenses	50.00%
Initial funding committed by award	$ 1,600,000