The Business and Summary of Significant Accounting Policies - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) segment	Sep. 30, 2023 USD ($)	Dec. 31, 2019 USD ($)
Business and Summary of Significant Accounting Policies
Contract and grant revenue	$ 26,000	$ 11,000	$ 155,000	$ 320,000
Number of segment | segment			1
Grant | Oncoceutics, Inc.
Business and Summary of Significant Accounting Policies
Deferred revenue	100,000		$ 100,000
Contract and grant revenue	24,000	0	200,000	30,000
Licensing
Business and Summary of Significant Accounting Policies
Contract and grant revenue	0	0	0	49,000
Emergent Biodefense Operations Lansing LLC
Business and Summary of Significant Accounting Policies
Revenue recognized	2,000	11,000	2,000	200,000
Ohara Pharmaceutical Co., Ltd.
Business and Summary of Significant Accounting Policies
License agreement, nonrefundable regulatory milestone payment to be received					$ 2,500,000
Ohara Pharmaceutical Co., Ltd. | Licensing
Business and Summary of Significant Accounting Policies
Contract and grant revenue	$ 0	$ 0	$ 0	$ 100,000