Serendipity in anticancer drug discovery

Table 3 List of drugs discovered to be beneficial for conditions other than for which they were developed (clinical)

Off-label drugs	Derivatives	No. of derivatives
Aminoglutethimide	NA	0
Alprostadil	Dinoprostone, carboprost, tromethamine, dinoprost, tromethamine, misoprostol	4
Amphetamine	Phentermine, methamphetamine, dextroamphetamine, alverine, selegiline, mephentermine, tranylcypromine, phenelzine, benzphetamine, diethylpropion	10
Aspirin	NA	0
Auranofin	NA	0
Carbamazepine	Oxcarbazepine	1
Celecoxib	NA	0
Chlordiazepoxide	Diazepam, temazepam, oxazepam, fludiazepam, clorazepate, halazepam, prazepam, flurazepam, lorazepam, cinolazepam, clonazepam, nitrazepam, bromazepam, flunitrazepam, quazepam, clotiazepam, alprazolam, estazolam, adinazolam, midazolam	20
Chlorothiazide	Benzthiazide, diazoxide, hydrochlorothiazide, hydroflumethiazide, bendroflumethiazide, cyclothiazide, polythiazide, trichlormethiazide, methyclothiazide, furosemide, bumetanide	11
Clofibrate	Fenofibrate	1
Dactinomycin	NA	0
Diisopropylfluorophosphate	NA	0
Diltiazem	NA	0
Dimenhydrinate	NA	0
Diphenhydramine	Bromodiphenhydramine, diphenylpyraline	2
Diphenoxylate	Loperamide	1
Dipyridamole	NA	0
Disulfiram	NA	0
Doxorubicin	Epirubicin, daunorubicin, idarubicin, valrubicin, plicamycin	5
Etomidate	NA	0
Finasteride	Dutasteride	1
Guanethidine	Debrisoquin, guanidine	2
Haloperidol	Droperidol	1
Imatinib	NA	0
Imipramine	Trimipramine, desipramine, clomipramine, protriptyline, amitriptyline, nortriptyline, cyclobenzaprine, maprotiline, doxepin, amoxapine	10
Iproniazid	Isocarboxazid	1
Linezolid	NA	0
Lysergic acid diethylamide	Cabergoline, lisuride, bromocriptine, nicergoline, pergolide	5
Meprobamate	Carisoprodol	1
Mercaptopurine	Thioguanine, azathioprine	2
Metronidazole	Tinidazole	1
Mifepristone	NA	0
Minoxidil	NA	0
Mycophenolic acid	Mycophenolatemofetil	1
Naloxone	Naltrexone	1
Norethindrone	Levonorgestrel, norgestrel, etonogestrel, gestodene,desogestrel, medroxyprogesterone, megestrol, progesterone, drospirenone, norelgestromin, ethynodioldiacetate	11
Pethidine	Anileridine	1
Phenobarbital	Methylphenobarbital, secobarbital, metharbital, aprobarbital, primidone, methsuximide	6
Prednisone	Medrysone, methylprednisolone, prednisolone, rimexolone, fluocortolone, desoximetasone	6
Probenecid	NA	0
Procarbazine	NA	0
Promethazine	Acepromazine, aceprometazine, acetophenazine, arphenazine, chlorpromazine, ethopropazine, fluphenazine, mesoridazine, methotrimeprazine, perphenazine, pipotiazine, prochlorperazine, promazine, propericiazine, propiomazine, thioproperazine, thioridazine, trifluoperazine, triflupromazine, trimeprazine	20
Quinacrine	Chloroquine, primaquine, hydroxychloroquine, amodiaquine	4
Reserpine	Deserpidine, rescinnamine	2
Salicyclic acid	Salsalate, olsalazine, diflunisal, mesalazine	4
Sildenafil	Tadalafil, vardenafil	2
Sirolimus	Everolimus	1
Tamoxifen	Toremifene	1
Terfenadine	Fexofenadine	1
Thalidomide	Lenalidomide	1
Tolazoline	NA	0
Trimethadione	Paramethadione	1
Zidovudine	Trifluridine, telbivudine, idoxuridine, zalcitabine, stavudine	5

NA: Not available.