A Phase 4 interventional study of Glyceryl Trinitrate (GTN) 0.2% Ointment and Glyceryl Trinitrate (GTN) 0.4% Ointment in Acute Anal Fissure, Anal Pain and Anorectal Disorders, sponsored by Hafiz Muhammad Hamza. Completed at 1 site in Pakistan. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-05-14.
Sponsored by Hafiz Muhammad Hamza · Phase 4, Interventional, and Treatment
The goal of this clinical trial is to compare the therapeutic efficacy and safety profile of Glyceryl Trinitrate (GTN) and Nifedipine ointments in the treatment of acute anal fissures in adults. The main questions it aims to answer are:
Which ointment is more effective in promoting fissure healing and symptom relief? What are the adverse effects associated with each treatment? Researchers will compare GTN and Nifedipine ointments to determine which provides better symptom resolution with fewer side effects.
Participants will:
Apply GTN or Nifedipine ointment topically twice daily for four weeks Attend follow-up visits for symptom assessment and adverse effect monitoring
Background and Rationale:
Anal fissures are painful linear tears in the anoderm, commonly caused by trauma from hard stool passage, leading to increased internal anal sphincter tone and ischemia. Acute fissures typically heal within six to eight weeks, while chronic fissures persist beyond this period. First-line treatment includes non-surgical options such as topical pharmacotherapy to reduce sphincter spasm and improve mucosal blood flow.
Glyceryl Trinitrate (GTN) and Nifedipine are widely used topical agents for anal fissure management. GTN acts as a nitric oxide donor, reducing sphincter tone via smooth muscle relaxation, though it is often associated with headaches. Nifedipine, a calcium channel blocker, lowers sphincter tone by inhibiting calcium influx into smooth muscle cells and has a more favorable side effect profile. Despite their widespread use, their comparative efficacy and safety remain a subject of debate.
This randomized controlled trial (RCT) aims to compare GTN and Nifedipine ointments in acute anal fissure treatment, evaluating symptom resolution, healing rates, and adverse effects to determine the optimal therapeutic choice.
Study Overview:
This double-blind, randomized, parallel-arm clinical trial will compare GTN and Nifedipine in patients with acute anal fissures. Participants will be allocated into:
GTN Group: Receiving either 0.2% or 0.4% GTN ointment, applied twice daily for four weeks.
Nifedipine Group: Receiving either 0.2% or 0.5% Nifedipine ointment, applied twice daily for four weeks.
The primary outcome is healing rate at four weeks, with secondary outcomes including pain reduction, side effects, patient satisfaction, and recurrence rates over six months.
Data Analysis:
Collected data will undergo statistical analysis using Chi-square tests, ANOVA, Kaplan-Meier survival analysis, and logistic regression modeling to identify treatment effectiveness and predictors of success.
Ethical Considerations:
The study is approved by the Federal Government Polyclinic Ethics Review Board, with written informed consent obtained from participants. All procedures comply with Good Clinical Practice (GCP) guidelines, and data confidentiality will be strictly maintained.
Expected Impact:
This study aims to refine treatment protocols for acute anal fissures, offering evidence-based guidance on the most effective and safest medical therapy, potentially reducing the need for surgical intervention.
87 studies on the registry are indexed under Rectal Diseases; 14 are open to participants now.
This study's enrollment of 110 is close to the median of 114 across 59 interventional studies indexed under Rectal Diseases.
Browse Rectal Diseases studies →Hafiz Muhammad Hamza is the lead sponsor of 2 studies on the registry; none are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants in this arm will apply 0.2% Glyceryl Trinitrate (GTN) ointment twice daily for four weeks. The primary goal is to assess its efficacy in healing acute anal fissures and symptom relief while monitoring for side effects such as headaches and dizziness.
Drug: Glyceryl Trinitrate (GTN) 0.2% Ointment
Participants in this arm will apply 0.4% Glyceryl Trinitrate (GTN) ointment twice daily for four weeks. This higher concentration aims to determine the dose-dependent efficacy and side effect profile compared to 0.2% GTN
Drug: Glyceryl Trinitrate (GTN) 0.4% Ointment
Participants in this arm will apply 0.2% Nifedipine ointment twice daily for four weeks. The study will evaluate its effectiveness in fissure healing, pain relief, and incidence of adverse effects such as local irritation or hypotension.
Drug: Nifedipine 0.2% Ointment
Participants in this arm will apply 0.5% Nifedipine ointment twice daily for four weeks. This higher concentration will assess whether increased potency provides superior symptom resolution and healing rates while monitoring potential side effects.
Drug: Nifedipine 0.5% Ointment
Participants will apply 0.2% Glyceryl Trinitrate (GTN) ointment to the anal region twice daily for four weeks. GTN functions as a nitric oxide donor, reducing internal anal sphincter tone to improve blood flow and promote fissure healing. The study aims to assess its effectiveness in symptom relief, fissure healing, and associated side effects such as headaches and dizziness.
Also known as: GTN 0.2%, Nitroglycerin 0.2% Ointment
Participants will apply 0.4% Glyceryl Trinitrate (GTN) ointment twice daily for four weeks. This increased concentration aims to determine dose-dependent efficacy and adverse effects in treating acute anal fissures. GTN acts by relaxing smooth muscle, decreasing sphincter tone, and enhancing mucosal blood flow to promote healing.
Also known as: GTN 0.4%, Nitroglycerin 0.4% Ointment
Participants will apply 0.2% Nifedipine ointment twice daily for four weeks. Nifedipine, a calcium channel blocker, reduces sphincter tone by inhibiting calcium influx into smooth muscle cells, leading to improved fissure healing. This arm will assess its effectiveness in symptom relief and healing rates, with a focus on side effects such as local irritation or hypotension.
Also known as: Nifedipine Gel 0.2%, Nifedipine 0.2%
Participants will apply 0.5% Nifedipine ointment twice daily for four weeks. This higher concentration is used to evaluate whether increased potency provides superior symptom resolution and healing rates compared to 0.2% Nifedipine. The study will also assess any potential adverse effects, including local irritation, dizziness, and hypotension.
Also known as: Nifedipine Gel 0.5%, Nifedipine 0.5%
Healing Rate at 4 Weeks
The proportion of participants achieving complete epithelialization of the anal fissure on clinical examination at the end of four weeks.
Time frame: 4 weeks
Change in Pain Scores (Visual Analog Scale [VAS])
Reduction in pain scores from baseline to post-treatment, measured using the Visual Analog Scale (VAS), a 10-point scale ranging from 0 (no pain) to 10 (worst possible pain). Higher scores indicate greater pain severity.
Time frame: 4 weeks
Incidence and Severity of Adverse Effects
Assessment of drug-related side effects, including headache, dizziness, local irritation, and hypotension, recorded throughout the study duration.
Time frame: 4 weeks
Patient Satisfaction with Treatment ( Self-validated Patient Satisfaction Score)
Evaluation of patient-reported satisfaction with treatment outcomes, assessed using a structured questionnaire. Scoring System: Patient satisfaction is assessed using the Self-validated Patient Satisfaction Score, with responses recorded on a 5-point Likert scale. The scoring system is as follows: * Very satisfied = 5 * Somewhat satisfied = 4 * Neutral = 3 * Somewhat dissatisfied = 2 * Very dissatisfied = 1 * Higher scores indicate greater patient satisfaction with treatment outcomes.
Time frame: 4 weeks
Time to Symptom Resolution
Duration until complete resolution of pain and cessation of rectal bleeding.
Time frame: 4 weeks
Plan to share: Undecided — At this stage, no final decision has been made regarding the sharing of individual participant data (IPD). Data sharing will be considered based on future research needs, ethical guidelines, and institutional policies. Any decision to share IPD will be made in compliance with data protection regulations and patient confidentiality standards.
Ran from Mar 2025 to primary completion in May 2025, 1 month.
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Studies of the drugs tested here: Nitroglycerin · Nifedipine
Hafiz Muhammad Hamza