AuthorisedTherapeutic exploratory (Phase II)Interventional

A Double-blind, Placebo-controlled Study to Evaluate the Safety, Tolerability, and Potential Antiseizure Activity of Adjunctive OV329 Therapy in Adults with Drug-Resistant Focal Epilepsy

Living with epilepsy can be challenging, especially when standard medicines do not stop seizures. This clinical trial is testing a new investigational drug called OV329 in adults aged 18 and older with drug-resistant focal epilepsy. Focal epilepsy means seizures start in one specific part of the brain. The main goal of the trial is to check the safety of OV329 and see how well the body handles it when taken alongside existing seizure medicines. Researchers will also look for early signs that it helps reduce seizures. To ensure fair testing, participants will be randomly chosen to receive either OV329 or a dummy pill (placebo) with no active medicine. Neither the participants nor the research team will know who receives which treatment during the study. Regular health checks, including heart tests and blood tests, will monitor safety throughout the trial.

At a glance

Status

Authorised

Phase

Therapeutic exploratory (Phase II)

Sponsor

Ovid Therapeutics Inc.

Enrolment target

Start

21 Aug 2026

Focal epilepsy

What is this study about?

Epilepsy is a common condition that affects the brain and causes frequent seizures. For many people, everyday medicines manage their symptoms well. However, around one in three people have drug-resistant epilepsy, meaning their seizures continue even after trying several different treatments. When seizures are hard to control, finding new and better medicines is essential.

This clinical trial is evaluating a new drug called OV329 as an 'add-on' treatment. This means participants continue taking their regular prescribed anti-seizure medicines while adding the study drug into their routine. Researchers want to find out whether OV329 can help bring better seizure control without causing troublesome side effects.

The study is a Phase II trial, which means it is an early step in testing how safe and useful the drug is in people with the condition. It uses a 'double-blind' and 'placebo-controlled' design. A placebo is a harmless dummy pill that looks identical to the real medicine. Comparing the real drug against a placebo helps scientists be sure that any changes or side effects are truly caused by the study medicine.

By taking part, volunteers help doctors understand whether OV329 could become a helpful future treatment option for people living with difficult-to-control focal epilepsy across the UK and worldwide.

Key takeaways

This study tests a new add-on drug called OV329 for adults with focal epilepsy.
It is aimed at people whose seizures have not stopped with standard medicines.
Participants will receive either the real medicine (OV329) or a dummy pill (placebo).
Doctors will closely check safety using regular heart, blood, and physical tests.
Participation is completely voluntary and you can withdraw at any time.

Who may be eligible?

This trial is open to adults aged 18 and over who have been diagnosed with focal epilepsy. To be considered, your seizures must be 'drug-resistant', meaning your current or past epilepsy medications have not been able to keep your seizures fully under control.

Both men and women can take part. Because OV329 is designed to be an add-on therapy, you will likely need to be on a stable dose of your usual anti-seizure medicines before joining.

Not everyone will be able to join. For example, people with other serious medical conditions, certain heart issues, or those taking specific medications that could clash with the study drug may not be eligible. The study doctor will check your full medical history to make sure taking part is safe for you.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

I am aged 18 or older.
I have been diagnosed with focal epilepsy.
My seizures continue despite taking standard anti-seizure medicines.
I am currently taking a stable dose of my regular epilepsy medication.
I am willing to attend regular hospital or clinic appointments for health checks.

Answer every question to see your result.

What does participation involve?

Taking part in this study involves adding either OV329 or a matching placebo to your daily routine for a set period. You will have regular clinic visits so the healthcare team can carefully monitor your health and well-being.

During clinic visits, doctors and nurses will perform routine checks. These include checking your vital signs (such as blood pressure and pulse), testing your heart with an electrocardiogram (ECG), taking blood and urine samples, and doing physical examinations. You will also be asked questions about your mood and how you are feeling, as changes in mood can sometimes happen with seizure medicines.

You will likely be asked to keep a simple seizure diary to record any seizures you experience. The study team will explain exactly how many visits you need to attend, how long each visit takes, and provide follow-up appointments after you finish taking the study medicine to ensure you remain well.

Potential risks and benefits

Taking part in this trial might help reduce your seizures, but there is no guarantee of direct personal benefit, especially as you might receive a placebo. However, your involvement will provide vital scientific knowledge that could help others with epilepsy in the future. As with any new medicine, there is a risk of side effects, which the medical team will monitor very closely through regular tests. Joining the trial is entirely your choice. You are free to leave the study at any time without giving a reason, and doing so will not affect your normal NHS care or your relationship with your doctors.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Netherlands

Common questions

What is focal epilepsy?

Focal epilepsy is a type of epilepsy where seizures start in one specific area or side of the brain, rather than affecting the whole brain at once.

Will I have to stop taking my regular epilepsy medicines?

No. OV329 is tested as an add-on therapy, meaning you will stay on your regular prescribed treatments while taking the study medication.

What is a placebo and why is it used?

A placebo is a dummy pill that looks just like the real medicine but contains no active ingredients. It helps researchers prove whether any health improvements or side effects are truly caused by OV329.

Will I know if I am getting the real drug or the placebo?

No. The trial is double-blind, meaning neither you nor your study doctors will know which pill you are taking until the study is completed.

Can I leave the study if I change my mind?

Yes, you can leave the trial at any point. Your decision will never affect the standard medical care you receive from your regular doctors.