Investigating What is the New Drug for OCD: Insights into Emerging Pharmacological Treatments

October 5, 2025 •

4 min read

While no single new drug has recently received widespread FDA approval specifically for obsessive-compulsive disorder (OCD) in 2025, a robust pipeline of investigational treatments is targeting refractory cases. For the approximately 40–60% of patients who do not respond adequately to first-line serotonin reuptake inhibitors (SSRIs), researchers are focusing on alternative neurobiological pathways, most notably the glutamate system.

Quick Summary

The search for new OCD medications is heavily focused on alternative mechanisms for treatment-resistant patients, with research exploring compounds that modulate the glutamate system, such as ketamine, memantine, and the now-abandoned troriluzole. Emerging psychedelics like psilocybin are also under investigation in controlled settings.

Key Points

No Single New Drug: There is no singular, new FDA-approved drug for OCD in 2025; instead, a pipeline of investigational treatments is being explored.
Targeting Glutamate: New pharmacological research is heavily focused on modulating the brain's glutamate system, moving beyond the traditional serotonin-focused SSRIs.
Troriluzole Discontinued: The promising glutamate modulator troriluzole was recently dropped from OCD development after a Phase 3 trial failed to meet its primary endpoint.
Psychedelics Under Study: Psychedelics like psilocybin and ketamine are showing potential in clinical trials for severe and treatment-resistant OCD, though they are still considered experimental.
Augmentation Strategies: For patients resistant to SSRIs, newer treatments are often being explored as an augmentation to existing medications rather than as standalone therapies.
Future Outlook: The future of OCD medication lies in more personalized treatments, targeting different neurobiological pathways to address the complex nature of the disorder.

Rethinking the Neurochemical Approach to OCD

Standard first-line treatments for obsessive-compulsive disorder have long centered on selective serotonin reuptake inhibitors (SSRIs), along with the tricyclic antidepressant clomipramine. While effective for many, these medications fail to provide sufficient relief for a significant portion of patients. This has led to a critical shift in pharmacological research away from the serotonin system and toward other neurotransmitters, particularly glutamate. The current landscape involves augmenting existing therapies with novel agents or exploring entirely new classes of drugs.

The Promising but Failed Story of Troriluzole

One of the most highly anticipated drug candidates for OCD was troriluzole (BHV-4157), a glutamate modulator developed by Biohaven Pharmaceuticals. Its development offers a clear illustration of the challenges and setbacks in novel OCD drug discovery.

The Mechanism Behind Troriluzole

Troriluzole is a prodrug of riluzole, which is FDA-approved for amyotrophic lateral sclerosis (ALS). Riluzole is believed to work by modulating glutamate, the brain's primary excitatory neurotransmitter. In some individuals with OCD, elevated glutamate activity is thought to drive symptom-related brain circuits. By regulating glutamate release, troriluzole was hypothesized to help restore normal brain activity. Early-stage research was promising, with small studies suggesting efficacy as an adjunctive treatment for severe or treatment-resistant OCD.

The Phase 3 Discontinuation

Despite earlier positive indications, Biohaven announced in 2025 that it was discontinuing the development of troriluzole for OCD. The decision followed the failure of its Phase 3 clinical trial to meet its primary outcome. This development highlights the difficulty of translating promising early-stage findings into clinically significant results in large-scale studies. While the potential for glutamate modulation in OCD remains high, troriluzole will not be the drug to bring this approach to market.

Glutamatergic Modulators in Development

Even with the setback of troriluzole, other glutamate-targeting agents are being explored, often as adjunctive therapies for treatment-resistant cases.

Memantine: An NMDA receptor antagonist approved for Alzheimer's disease, memantine blocks sustained activation of glutamate receptors. Several controlled trials have explored its use to augment SSRIs, showing some promising outcomes.
N-acetylcysteine (NAC): This over-the-counter supplement attenuates glutamate transmission and has been studied for refractory OCD. While results have been mixed, it continues to be explored as a potential adjunctive treatment.
Ketamine: Known for its rapid antidepressant effects, ketamine is an NMDA receptor antagonist that can quickly reduce OCD symptoms for some individuals. Studies show its potential, particularly for rapid relief, though effects can be short-lived. Ketamine is not yet FDA-approved for OCD but is used off-label in some clinics.

Emerging Psychedelics as OCD Treatment

In recent years, research has expanded to include psychedelic compounds like psilocybin, known for its ability to increase neural plasticity.

Psilocybin: Found in certain mushrooms, psilocybin has shown promising results in clinical trials for severe OCD. A recent randomized, controlled trial exploring different dosing strategies has been registered on ClinicalTrials.gov. Preliminary findings suggest a significant reduction in symptom severity, with effects potentially lasting for months. As with ketamine, this research is still in controlled experimental phases.

Comparison of Standard vs. Novel OCD Medications


Feature	Standard SSRIs/Clomipramine	Emerging Glutamate Modulators (e.g., Memantine, Ketamine)	Emerging Psychedelics (e.g., Psilocybin)
Mechanism	Increases serotonin levels	Modulates glutamate transmission	Increases neuroplasticity, affects serotonin receptors
Treatment Target	First-line treatment for all OCD	Augmentation for treatment-resistant OCD	Experimental for severe, treatment-resistant OCD
Speed of Effect	Weeks to months	Potentially rapid onset (e.g., ketamine)	Potentially rapid and sustained effect
Availability	Widely available, FDA-approved	Many used off-label, investigational	Experimental, limited to clinical trials
Side Effects	Sexual dysfunction, weight gain, nausea	Psychotic symptoms (amantadine), dizziness, confusion	Hallucinations, temporary disorientation

The Outlook for New OCD Medications

While the path to a new FDA-approved drug for OCD is filled with challenges, the research pipeline remains active, particularly for those with treatment-resistant symptoms. The shift in focus from solely serotonin-based approaches to exploring other neurotransmitter systems, such as glutamate, represents a significant evolution in pharmacology. Neuromodulation techniques like repetitive Transcranial Magnetic Stimulation (rTMS) are also gaining ground, with some devices receiving FDA clearance for OCD. The ongoing research into agents like ketamine and psilocybin offers hope for faster-acting and more durable treatment options. For those struggling to find relief, the development of these new therapies, along with advanced methods like genetic testing to inform medication choices, signifies a more personalized and hopeful future for OCD treatment. However, it is crucial to remember that these are not yet standard practice and should only be pursued under strict medical supervision.

Conclusion

In summary, the search for what is the new drug for OCD reveals a landscape of ongoing clinical trials rather than a single, recently approved breakthrough. The failure of troriluzole's Phase 3 trial serves as a reminder of the scientific process, but the robust investigation into alternative mechanisms—including glutamate modulation and psychedelics—offers renewed hope for patients with treatment-resistant OCD. The future of OCD pharmacology points toward a more diversified and individualized approach, with multiple pathways being explored to provide relief beyond the current standard of care.

International OCD Foundation: Medication

Frequently Asked Questions

While there is no single new medication that has recently received FDA approval, extensive research is underway for treatments aimed at treatment-resistant OCD. The focus has largely shifted to new drug targets beyond the serotonin system.

Troriluzole, a glutamate modulator, was an investigational drug that showed early promise for OCD. However, its development for OCD was discontinued by Biohaven Pharmaceuticals in 2025 after a Phase 3 clinical trial failed to meet its primary endpoint.

Yes, several medications that modulate the glutamate system are being investigated for OCD, including memantine, N-acetylcysteine (NAC), and ketamine. These are often used as adjunctive treatments, particularly for treatment-resistant cases.

Psilocybin is an emerging experimental treatment for severe, treatment-resistant OCD, with preliminary clinical trials showing promising results. However, it is not an FDA-approved treatment and is only available within structured research settings.

Beyond standard SSRIs and investigational drugs, other options for treatment-resistant OCD include neuromodulation techniques like deep Transcranial Magnetic Stimulation (dTMS), which has received FDA clearance for OCD.

Standard SSRIs are the first-line treatment, while many of the newer options are still experimental and primarily reserved for treatment-resistant cases. Unlike SSRIs, which primarily affect serotonin, new treatments often target different neurotransmitter systems like glutamate and may offer faster or more robust effects for some individuals.

Ketamine is not FDA-approved for OCD but is sometimes used off-label in clinical settings for treatment-resistant cases, particularly for its potential to provide rapid symptom relief. Its use typically requires ongoing therapy and may involve repeated infusions to sustain effects.