This is a list of investigational obsessive–compulsive disorder drugs, or drugs that are currently under development for clinical use in the treatment of obsessive–compulsive disorder (OCD) but are not yet approved.

Chemical/generic names are listed first, with developmental code names, synonyms, and brand names in parentheses.

This list was last comprehensively updated in September 2021. It is likely to become outdated with time.

• Immunoglobulin (immune globulin 10%, 10% high purity immunoglobulin, 10% IVIG, NewGam, Newnorm, Octagam 10%, Octagam, Panzyga) – immunoglobulin / immunostimulant [1]^[1]
• Troriluzole (BHV-4157, BHV-4157a, FC-4157; trigriluzole) – prodrug of riluzole / glutamate modulator [2]^[1]

• Cannabis extracts (various) – cannabinoid receptor modulators [3]

• 4'-Fluorocannabidiol (4'-F-CBD; fluorinated cannabidiol; HUF-101, HUF-102, HUF-103) – cannabinoid receptor modulator, other actions [4]
• AbbVie/Rugen research programme – unspecified mechanism of action [5]
• Agomelatine (Alodil, Melitor, Thymanax, Valdoxan, Vestin; AGO-178, AGO178C, S-20098, S-20098-F55) – serotonin 5-HT_2C receptor antagonist and melatonin receptor agonist [6]
• CR-5542 – orexin receptor antagonist [7]
• Dual SSRIs and serotonin 5-HT_1A receptor agonists (SSA-426, WAY-163426, WAY-211612, WAY-253752, WAY-426) [8]
• Risperidone (Risperdal, Risperdal Consta, Risperdal Depot; JNJ-410397-AAA, R-64766, R064766) – atypical antipsychotic / monoamine receptor modulator [9]
• Secretin (SecreFlo; INN-329, RG-1068) – hormone/diagnostic agent [10]
• Sosei Heptares research programme – various mechanisms of action [11]

• Bitopertin (R-1678, RG-6718, RG1678, RO-4917838) – glycine GlyT1 inhibitors / glycine reuptake inhibitor [12]
• Cycloserine (D-cycloserine; TIK-101) – glutamate NMDA receptor partial agonist [13]
• Elzasonan (CP-448187, CP-448187-01) – serotonin 5-HT_1B and 5-HT_1D receptor antagonist
• F-14258 – serotonin 5-HT_1B and 5-HT_1D receptor antagonist
• Fluoxetine/naltrexone (OREX-004) – selective serotonin reuptake inhibitor and opioid receptor antagonist [14]
• Mavoglurant (AFQ-056) – glutamate mGlu5 receptor antagonist [15]
• NPL-2003 – glutamate modulator [16]
• Ondansetron (Setrodon; TO-2061) – serotonin 5-HT₃ receptor antagonist [17]^[1]
• RO-600175 – serotonin 5-HT_2C receptor agonist [18]
• Roxindole (EMD-49980) – dopamine receptor agonist, serotonin receptor modulator, adrenergic receptor modulator, and serotonin reuptake inhibitor [19]
• SB-200646 (SB-200646A) – serotonin 5-HT_2B and 5-HT_2C receptor antagonist [20]

• 5-HT₆ receptor agonists (e.g., WAY-181187, WAY-208466)^[2]
• Antiandrogens (e.g., flutamide, cyproterone acetate, triptorelin)^[3]
• Cannabinoids (e.g., nabilone, tetrahydrocannabinol (THC)/cannabis) – cannabinoid receptor modulators^[1]
• NMDA receptor modulators (e.g., ketamine, memantine, nitrous oxide, rapastinel)^[1]
• Nonsteroidal anti-inflammatory drugs (NSAIDs) (e.g., celecoxib, naproxen) – cyclooxygenase inhibitors^[1]
• Rituximab (Rituxan) – monoclonal antibody against CD20^[1]
• Serotonergic psychedelics (e.g., psilocybin/psilocybin mushrooms, lysergic acid diethylamide (LSD)) – serotonin receptor modulators^{[4][5][6][7][1]}
• Tolcapone (Tasmar) – catechol-O-methyltransferase inhibitor^[1]

• Clomipramine (Anafranil) – tricyclic antidepressant / monoamine reuptake inhibitor and receptor modulator [21]
• Escitalopram (S-citalopram; Cipralex, Entact, Lexapro, Seroplex, Sipralex, Sipralexa; LU-26054; MLD-55) – selective serotonin reuptake inhibitor [22]
• Fluoxetine (Prozac, Prozac Weekly, Reneuron, Sarafem; LY-110140) – selective serotonin reuptake inhibitor [23][24]
• Fluvoxamine (Depromel, Luvox, Luvox CR; SME-3110) – selective serotonin reuptake inhibitor and sigma-1 receptor agonist [25]
• Paroxetine (Aropax, Deroxat, Divarius, Dropax, Dropaxin, Frosinor, Motivan, Paxil, Paxil CR, Serestill, Seroxat, Tagonis; BRL-29060, BRL-29060A, FG-7051, NNC-207051, SI-211103) – selective serotonin reuptake inhibitor [26][27]
• Sertraline (Aremis, Besitran, Gladem, J Zoloft, Lustral, Serad, Serlain, Tatig, Zoloft; CP-51974, CP-51974-01) – selective serotonin reuptake inhibitor [28]

• Atypical antipsychotics (e.g., aripiprazole, olanzapine, quetiapine, risperidone) – monoamine receptor modulators

• List of investigational drugs

• Berlin HA, Hamilton H, Hollander E (2008). "Experimental therapeutics for refractory obsessive-compulsive disorder: translational approaches and new somatic developments". Mt Sinai J Med. 75 (3): 174–203. doi:10.1002/msj.20045. PMID 18704978.
• Marazziti D, Dell'Osso L (April 2015). "Why have early investigational therapies of obsessive-compulsive disorder failed to materialise?". Expert Opin Investig Drugs. 24 (4): 455–8. doi:10.1517/13543784.2015.1005735. PMID 25599971.
• Grassi G, Cecchelli C, Vignozzi L, Pacini S (2020). "Investigational and Experimental Drugs to Treat Obsessive-Compulsive Disorder". J Exp Pharmacol. 12: 695–706. doi:10.2147/JEP.S255375. PMC 7801912. PMID 33447096.

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