The Phosphodiesterase Inhibitor Tadalafil as an Adjunct to Antidepressants in Major Depressive Disorder Patients

NCT05030623 | Withdrawn Phase 1 DMC

• 1 other identifier: 15/2021NEUR
• Study Type: interventional
• Target: N/A
• Locations: 1 country
• Sites: 1

Brief Summary

Antidepressant-like effects of tadalafil to its ability to modulate transduction pathways responsible for neuroplasticity. Treatment with tadalafil was shown to be PKG-dependent and lead to increased expression of cGMP, pCREB, BDNF and VGF in the hippocampus and prefrontal cortex (PFC), brain areas relevant to mood disorders pathophysiology. Low-dose tadalafil improved both depressive symptoms in patients with erectile dysfunction.

Conditions

Major Depressive Disorder

Outcome Measures

Primary Outcomes (1)

• Effect on Hamilton Depression rating scale score (HAM-D score)

  The principal measure of the outcome was the 17-items HAM-D. Scoring is based on the 17-item scale and scores of 0-7 are considered as being normal, 8-13 suggest mild depression, 14-17 moderate depression and scores over 17 are indicative of severe depression. Remission is defined as HAM-D total score ≤ 7 (primary outcome). Treatment response is defined as ≥ 50% drop in the HAM-D total score.

  12 weeks

Secondary Outcomes (1)

• Effect on biological markers

  At baseline and after 12 weeks of intervention

Study Arms (2)

Tadalafil

EXPERIMENTAL

Drug: Tadalafil 5Mg Tab

Placebo

PLACEBO COMPARATOR

Drug: Placebo

Interventions

Tadalafil 5Mg Tab DRUG

Tadalafil 5Mg Tab plus Fluoxetine 20 mg capsule

Tadalafil

Placebo DRUG

Placebo Tab plus Fluoxetine 20 mg capsule

Placebo

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Eighty adult outpatients with the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) diagnosis of MDD based on a MINI Neuropsychiatric Interview (MINI) (American Psychiatric Association., 2000; Sheehan et al., 1998), without psychotic features and a total 17 item HAM-D score of at least 18 with item 1 (depressed mood) scored 2 or greater were eligible (Hamilton, 1960).
• Patients were requested to be free of all the psychotropic and anti-inflammatory medications for at least 4 weeks before participating in the study.

You may not qualify if:

• Patients with bipolar I or bipolar II disorder Patients with personality disorders Patients with eating disorders Patients with substance dependence or abuse Patients with concurrent active medical condition Patients with history of seizures Patients with history of receiving Electroconvulsive therapy (ECT) Patients with inflammatory disorders Patients with allergy or contraindications to the used medications Patients with finally pregnant or lactating females Cardiovascular disorders Severe renal impairment: creatinine clearance of ≤ 25 ml/min Moderate or severe hepatic impairment

Sponsors & Collaborators

• Sadat City University: lead

Study Sites (1)

Faculty of Pharmacy

Shibīn al Kawm, Menoufia, 13829, Egypt

Location

MeSH Terms

Conditions

Depressive Disorder, Major

Interventions

Tadalafil

Condition Hierarchy (Ancestors)

Depressive Disorder; Mood Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Carbolines; Pyridines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Indole Alkaloids; Indoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds, 3-Ring

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Lecturer of Clinical Pharmacy

Study Record Dates

• First Submitted: August 30, 2021
• First Posted: September 1, 2021
• Study Start: August 1, 2021
• Primary Completion: December 31, 2024
• Study Completion: December 31, 2024
• Last Updated: July 14, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF

Locations

EG (1)