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Evaluation of Trazodone Hydrochloride for Improving Emotional Blunting in Patients with Major Depressive Disorder

Verified siteFast replyRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

The study focuses on people with Major Depressive Disorder who still feel a reduced ability to experience or show emotions, a problem called emotional blunting, after trying other antidepressants such as SSRIs (a common type of medicine that increases certain brain chemicals) or SNRIs (another type that works on two brain chemicals). The medication being tested is trazodone, an antidepressant that works in a different way from the usual drugs. The purpose of the study is to evaluate whether 8 weeks of treatment with trazodone improves emotional blunting in this group of patients.

Participants will take the study medication by mouth once a day for about two months. At the beginning and after the eight‑week period, they will complete the Oxford Depression Questionnaire (ODQ), a set of questions that measures how often different feelings are experienced. Additional questionnaires will ask about overall mood, thinking and memory (cognition), sleep quality, daily functioning at work, school, or home, and overall quality of life. The study follows a simple schedule of visits and questionnaire completion without any invasive procedures.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Baseline assessment

    At the first visit after joining the study, you will sign the consent form and confirm that you have major depressive disorder and have previously used SSRI or SNRI medication without full improvement.

    You will complete several questionnaires, including the Oxford depression questionnaire (odq) that measures emotional experiences, as well as additional forms that evaluate depression severity, cognition, sleep quality, overall quality of life, and ability to function at work, school, or at home.

  2. Step 2

    Receive study medication

    After the baseline assessment, you will be given a supply of trazodone prolonged-release tablets. The tablet strength will be either 75 mg or 150 mg, depending on the random assignment of the study.

    The tablets are taken by mouth. You will be instructed to take one tablet each day for the entire study period.

  3. Step 3

    Daily medication period (8 weeks)

    You will take the assigned trazodone tablet every day for eight weeks. The medication is designed to release the drug slowly over time, which helps maintain a steady level in your body.

    During this time you should continue your usual daily routine and report any side effects or health changes to the study staff as instructed.

  4. Step 4

    Final assessment (week 8)

    At the end of the eight‑week treatment period, you will return for a final visit.

    You will complete the same set of questionnaires that were filled out at the beginning, including the odq, to allow comparison of your emotional experience before and after treatment.

    The study staff will collect the medication containers and record any observations about your health during the trial.

Who can join the trial?

8 criteria

  • You must be an adult between 18 and 65 years old, able to visit the clinic without staying overnight (outpatient), and you can be any gender or ethnic background.
  • You need a diagnosis of Major Depressive Disorder (MDD) – a type of depression – either for the first time or more than once, according to the standard guide called DSM‑5 (a manual doctors use to define mental health conditions).
  • Your current depressive episode (a period when depression symptoms are present) must have started less than 12 months ago.
  • You must score between 22 and 28 on the MADRS questionnaire, which measures how severe your depression is.
  • You must have taken a single antidepressant from the SSRI or SNRI groups (examples: citalopram, escitalopram, paroxetine, duloxetine, venlafaxine) for at least 6 weeks at a dose that is considered enough (monotherapy), but it did not improve your symptoms enough (inadequate response), and your doctor thinks you should switch to a different medication.
  • While still on that antidepressant, you need a score of 50 or higher on the ODQ questionnaire, which measures how you experience and express emotions.
  • You must sign a written informed consent form, agreeing to join the study and allowing the use of your personal data, before any study procedures begin.
  • If you are a woman who could become pregnant, you must have a negative pregnancy test at the start of the study and agree not to become pregnant from the time you sign the consent until the third visit. You must use an effective birth‑control method such as hormonal pills, injections, patches, an IUD or IUS, a condom combined with another method, sterilization (tubal occlusion or vasectomy), or agree to avoid sexual activity.

Who cannot join the trial?

13 criteria

  • If you have any condition that makes taking the study drug unsafe according to the official medication guide (contraindications in the SmPC), you cannot join.
  • If you have not responded well to two previous antidepressant treatments that were given at the right dose and for enough time, you are excluded.
  • If you are known to be allergic (hypersensitivity) to the active ingredient or any part of the study medication, you cannot participate.
  • If you currently have any of the following mental health conditions: bipolar disorder, schizophrenia, other psychotic disorders, a severe personality disorder, mental retardation (intellectual disability), organic mental disorders (brain‑related mental problems), or mental disorders caused by a medical illness, you are excluded.
  • If you have a significant neurological condition (such as epilepsy or multiple sclerosis) or any neurodegenerative disease (a disease that gradually damages the brain or nerves), you cannot join.
  • If you are currently taking antipsychotic medicines or mood stabilizer medicines, you are excluded.
  • If you are considered at risk of suicide, defined by a score of 4 or higher on item #10 of the MADRS (a depression rating scale), you cannot participate.
  • If you are pregnant or breastfeeding (lactation), you are excluded.
  • If a physical exam or vital‑sign check shows important health problems that the doctor thinks could interfere with the study, you cannot join.
  • If you have known heart disease, especially if your heart’s electrical timing (QT interval) is too long (greater than 450 ms for men or 470 ms for women, measured as QTcF), you are excluded.
  • If you are unable to follow the study rules, such as being uncooperative, unable to attend study visits, or unlikely to finish the trial, you cannot participate.
  • If you are involved in conducting the study (for example, an investigator, a close relative of the investigator, a pharmacist, or study staff), you are excluded.
  • If you have taken part in another experimental clinical trial within the past three months, you cannot join.
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Investigated drugs

Trazodone is a tablet taken by mouth that slowly releases the medicine over time. It works on brain chemicals to treat depression. In this study, people with major depressive disorder who did not fully improve with other antidepressants are receiving trazodone. The aim is to find out if eight weeks of treatment can help them feel, express, and manage their emotions—both good and bad—more effectively.

What is already known about the treatment

  • Trittico AC 150 mg retard tabletta

    The medication is taken by mouth as a prolonged‑release tablet, providing a steady dose over several hours. Trazodone is an approved antidepressant that has been studied for many years and is listed in major medical references. It is mainly used to treat major depressive disorder, especially when other antidepressants have not fully worked. It works by blocking the re‑uptake of serotonin and also blocking certain serotonin receptors, which helps increase serotonin activity in the brain; it belongs to the class of serotonin antagonist and reuptake inhibitors (SARIs).

  • TRITTICO CR, 75 mg, tabletki o przedłużonym uwalnianiu

    This product is an oral prolonged‑release tablet that releases the drug slowly after swallowing. Trazodone is a well‑known antidepressant with a long history in medical literature and is approved for clinical use. It is prescribed for major depressive disorder, particularly in patients who have not responded completely to other treatments. The drug increases serotonin levels by inhibiting its re‑uptake and blocking specific serotonin receptors, and it is classified as a serotonin antagonist and reuptake inhibitor (SARI).

  • Trittico 150 mg prolonged-release tablets

    The drug is administered orally as a prolonged‑release tablet, allowing the medication to be absorbed gradually. Trazodone is an established antidepressant that appears in standard medical references and is widely used worldwide. Its main use is for major depressive disorder, especially when previous antidepressant therapy was only partially effective. It works by preventing serotonin re‑uptake and antagonizing certain serotonin receptors, thereby boosting serotonin activity; it is classified as a serotonin antagonist and reuptake inhibitor (SARI).

  • Trittico 75 mg prolonged-release tablets

    This medication comes as an oral prolonged‑release tablet that delivers the active ingredient steadily over time. Trazodone is a recognized antidepressant with extensive study and approval in many countries. It is primarily indicated for major depressive disorder, often for patients who need additional help beyond other antidepressants. Its action involves blocking serotonin re‑uptake and certain serotonin receptors, increasing serotonin signaling, and it belongs to the serotonin antagonist and reuptake inhibitor (SARI) class.

  • TRITTICO CR, 150 mg, tabletki o przedłużonym uwalnianiu

    The product is taken by mouth as a prolonged‑release tablet, providing a consistent release of medication after ingestion. Trazodone is an approved and well‑documented antidepressant found in major medical literature. It is mainly prescribed for major depressive disorder, especially in cases where other antidepressants have not given a full response. Its mechanism involves inhibiting serotonin re‑uptake and blocking specific serotonin receptors to raise serotonin activity, and it is categorized as a serotonin antagonist and reuptake inhibitor (SARI).

Investigated diseases

Major depressive disorder - Major depressive disorder is a mental health condition characterized by persistent low mood, loss of interest, and a range of emotional and physical symptoms. The condition typically develops gradually, with symptoms lasting for at least two weeks and often worsening over time if untreated. Individuals may experience difficulties in thinking, sleeping, and daily functioning, and the symptoms can fluctuate in intensity. The disorder can become chronic, with episodes recurring or persisting for months.
Trial detailsLast updated 19 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2025-523267-38-00Protocol code039(Z)MD25052Estimated enrolment120 patientsSponsorAngelini Pharma Italia Aziende Chimiche Riunite Angelini Francesc O A.C.R.A.F. S.p.A.

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