Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 31, 2020
Cover
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-37939
Document Period End Date	Sep. 30, 2020
Entity Registrant Name	MARKER THERAPEUTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-4497941
Entity Address, Address Line One	3200 Southwest Freeway
Entity Address, Address Line Two	Suite 2500
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77027
City Area Code	713
Local Phone Number	400-6400
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	MRKR
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		48,025,102
Entity Central Index Key	0001094038
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false