Not yet recruitingNAINTERVENTIONAL

Signature Response to Light Therapy in Unipolar and Bipolar Major Depressive Episode (MDE)

This study is exploring why light therapy works for some people suffering from a Major Depressive Episode (MDE), which is a common and serious form of depression. While many treatments exist, they don't work for everyone, and depression can severely impact daily life. Researchers want to understand the different ways people respond to light therapy, aiming to find better ways to treat depression that also help with sleep and alertness. They'll be looking at how therapy changes biological markers in the body and clinical symptoms. The main goal is to identify patterns that predict who will benefit most from light therapy and determine the most effective ways to use it. This research could lead to more personalised and effective treatments for depression.

At a glance

Status

Not yet recruiting

Phase

Sponsor

Assistance Publique - Hôpitaux de Paris

Enrolment target

173

Start

01 Mar 2026

Estimated completion

01 May 2029

Major Depressive Episode

What is this study about?

This study is particularly interested in understanding how light therapy helps people who are experiencing a Major Depressive Episode (MDE). MDE is a very common and serious mental health condition that can make daily life very difficult. It can affect your mood, your ability to function, and your overall quality of life. Unfortunately, current treatments, including some medications, don't work for everyone, and sometimes only help about half of the people who try them. This means doctors are always looking for better and more effective treatments.

Light therapy has shown promise as a treatment for depression, sometimes working as well as antidepressants, and it has extra benefits like helping with sleep and alertness, which are often affected by depression. However, we don't fully understand why it works for some people and not others, or what the best way to use it is. This study aims to dig deeper into these questions. Researchers want to examine the links between different measurements in the body and how people feel, both before and after light therapy.

The main goal is to find what they call a 'signature response' – basically, a set of changes or patterns that show someone is responding well to light therapy. This could involve looking at various biological markers (things in your body) and how your symptoms change. By understanding these patterns, the hope is to be able to predict who will benefit most from light therapy and to figure out the most effective ways to use it, ultimately leading to better, more personalised care for people with depression.

Key takeaways

This study investigates how light therapy helps people with depression.
It aims to understand why some individuals respond well and to find the best ways to use light therapy.
Researchers will study your mood, sleep, alertness, and biological rhythms.
The goal is to discover patterns that predict who benefits most from light therapy.
This research could lead to more personalised and effective depression treatments.

Who may be eligible?

To join this study, you need to be an adult between 18 and 65 years old and have been diagnosed with a Major Depressive Episode, which could be part of either unipolar or bipolar disorder. Your doctor would have assessed your depression symptoms as moderate to severe. Importantly, light therapy must be a treatment option your doctor has already prescribed for you.

If you have bipolar disorder, you'll need to be on stable medication to manage your mood (like Lithium, Valproate, or specific antipsychotics) for at least four weeks before starting the study. You'll also need to be able to understand French and agree to take part by signing a consent form.

There are certain reasons why you might not be able to join. For example, if you have other serious mental health conditions like schizophrenia, or if you've recently started other antidepressant treatments besides light therapy or mood stabilisers. Also, if light therapy was used in the last month, or if previous treatments for your current depressive episode haven't worked after trying two different types of antidepressants, you wouldn't be able to participate. Lastly, certain eye conditions like cataracts or glaucoma would prevent you from taking part.

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.

Are you between 18 and 65 years old?
Have you been diagnosed with a Major Depressive Episode?
Has your doctor prescribed light therapy for your depression?
If you have bipolar disorder, are you on stable mood-managing medication?
Are you able to speak and understand French?

Answer every question to see your result.

What does participation involve?

The study aims to understand your response to light therapy. It involves a series of visits, during which researchers will make measurements of your sleep, alertness, body rhythms, and how light affects your body. You will also have clinical evaluations to assess your depression symptoms. The main measure of how well light therapy is working will be based on a score used by doctors, looking for at least a 50% improvement in your symptoms between your first and fourth visit. The total duration of your participation, including all visits and assessments, will depend on the length of the light therapy treatment protocol prescribed by your doctor.

Potential risks and benefits

Taking part in this study could potentially help researchers better understand how light therapy works, which might lead to more effective treatments for depression in the future. While light therapy is generally considered safe, some people might experience mild side effects like eye strain, headaches, or irritability. However, these are usually temporary. There's also the benefit of receiving the light therapy prescribed by your doctor. You are completely free to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

Bichat - Claude-Bernard Hospital
Verified postcode
Paris, France

Common questions

What is a Major Depressive Episode (MDE)?

An MDE is a period of at least two weeks where a person experiences a low mood or loss of interest or pleasure, along with other symptoms like changes in sleep, appetite, energy, concentration, or feelings of worthlessness.

What is light therapy?

Light therapy involves sitting in front of a special light box that emits bright light, usually in the morning. It's thought to help regulate your body's natural clock and improve mood.

How long does the light therapy treatment last?

The study itself doesn't define the length of the light therapy, but it will follow the treatment plan prescribed by your doctor. The study will assess you from your first visit until the end of your prescribed light therapy.

Will I receive any new treatments in this study?

No, this study is observing the effects of light therapy that has already been prescribed for you by your doctor. It's not testing a new treatment, but rather studying how an existing one works.

What do 'biological markers' mean?

Biological markers are things like changes in your hormones, sleep patterns, or other bodily functions that researchers can measure to understand how your body is responding to treatment.

How to find out more

Pierre-Alexis GEOFFROY, Pr

pierrealexis.geoffroy@aphp.fr +33 1 40 25 62 72 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.