Table 1.

Drug class, specific drug, and drug targets of repurposed agents currently undergoing preclinical investigation.

Drug Class	Drugs	Targets	Reference(s)
Antiarrhythmics	Digoxin	Na+/K+ ATPase, AKT	[19]
	Proscillaridin A	GSK3β	[20]
Antibiotics	Tetracyclines	Mitochondria	[21,22]
	Dapsone	FPR, IL-8, Leukotriene-B4	[23]
	Clofazimine	Cx46	[24]
Antidiabetics	Repaglinide	BCL-2, PD-L1, Beclin 1	[25]
Antidepressants	Imipramine	ATG7	[26]
	Clomipramine	Complex III Cytochrome B	[27]
	Fluvoxamine	AKT/mTOR	[28]
	Sertraline	MAPK	[29]
Anti-inflammatories	IP187B/Aspirin	STAT3, NF-κB, IGFR, PD-1	[28,30,31,32,33]
	Celecoxib	COX-2, NF-κB	[34,35,36]
	Ibudilast	MIF	[37]
	Sulfasalazine	System X(c)(-) Antiporter	[38,39]
Immunosuppressants	Everolimus	mTOR, MCL-1	[40,41,42]
	Sirolimus
	Temsirolimus
Antihypertensives	Mibefradil	NHEJ, Cav3.2	[43]
	Prazosin	AKT	[32]
	Amlodipine	PKD, Caspase 3	[44]
	Pentoxifylline	NA	[45]
Antipsychotics	Thioridazine	AMPK, MAP1/LC3-II, WNT	[46,47,48]
	DS00329	Cyclin A, Cyclin B, Cyclin D1	[49]
	Chlorpromazine	CcO Complex IV	[50,51]
	Fluspirilene	STAT3	[52]
	Penfluridol	SOX2, OCT4, uPAR	[53]
	Olanzapine	AMPK	[54]
	Quetiapine	WNT	[55]
	Brexpiprazole	Survivin	[56]
Antivirals	Simeprevir	PI4K	[57]
	Ribavirin	EZH2, ERK	[58]
Biologics and Small-Molecule Inhibitors	AS602801	JNK	[59]
	CEP-1347		[60]
	LY294002	PI3K	[61]
	PX-886		[61]
	Ibrutinib	TK, BMX-STA3	[62]
	Roscovitin	CDK	[63]
	Binimetinib	MEK	[64]
	Encorafenib	BRAF	[64]
Disulfiram	Disulfiram	PLK1, Ubiquitin–Proteasome Pathway, AIF	[65,66,67,68]
Methylxanthines	Theophylline	PDE
	Theobromine		[69]
	Caffeine
Neurocognitive	Riluzole	Na+ Transporter, ITAF hnRNP A1, HIF1A, AKT	[70,71,72]
	Dimethyl fumarate	ERK1/2, AKT	[73]
	Idebenone	p21	[74]
Statins	Lovastatin	c-Myc, SKP2	[75,76]
	Simvastatin	EGFR, FGFR, c-SRC	[77]
	Atorvastatin	RAS	[78]
Other	Aurintricarboxylic acid	NF-κB	[79]
	Papaverine	HMGB1/RAGE	[80]
	Bacoside A	CAMKIIA	[81]
	Verteporfin	YAP, HIF1A	[82]
	Clomiphene	IDH1	[83]

Abbreviations: protein kinase B (AKT); glycogen synthase kinase (GSK3B); formyl peptide receptor (FPR); interleukin-8 (IL-8); connexin 46 (Cx46); B-cell lymphoma 2 (BCL2); programmed death-ligand 1 (PDL1); autophagy related 7 (ATG7); mechanistic target of rapamycin (mTOR); mitogen-activated protein kinase (MAPK); signal transducer and activator of transcription 3 (STAT3); nuclear factor kappa-light-chain-enhancer of activated B cells (NF-KB); insulin growth factor receptor (IGFR); programmed cell death protein 1 (PD-1); cyclooxygenase-2 (COX2); macrophage migration inhibitory factor (MIF); induced myeloid leukemia cell differentiation protein (MCL-1); non-homologous end-joining (NHEJ); polycystin-1 (PKD); microtubule-associated protein 1A (MAP1)/1B-light chain 3 phosphatidylethanolamine conjugate (LC3-II); cytochrome c oxidase (CcO, complex IV); (sex determining region Y)-box 2 (SOX2); octamer-binding transcription factor 4 (OCT4); urokinase plasminogen activator surface receptor (uPAR); AMP-activated protein kinase (AMPK); phosphatidylinositol 4-kinase (PI4K); enhancer of zeste homolog 2 (EZH2); extracellular signal-regulated kinase (ERK); S-phase kinase protein (Skp2); epidermal growth factor receptor (EGFR); fibroblast growth factor receptor (EGFR); proto-oncogene tyrosine-protein kinase Src (c-SRC); rat sarcoma (RAS); high-mobility group protein 1 (HMG-1); receptor for advanced glycation endproducts (RAGE); Ca2+/calmodulin-dependent protein kinase II (CAMKII); isocitrate dehydrogenase 1 (IDH1).