Low-Dose Versus Conventional-Dose Oral Isotretinoin for Acne Vulgaris

June 5, 2026 updated by: Nareeman Ur Rehman, Pakistan Institute of Medical Sciences

Comparing the Efficacy and Safety of Low-Dose Oral Isotretinoin Versus Conventional-Dose in the Treatment of Acne Vulgaris

Background and Purpose:

Acne vulgaris is a common skin condition that can cause significant physical and emotional distress. Oral isotretinoin is a highly effective treatment for severe or persistent acne. While the standard (conventional) dose is effective, it is often associated with side effects like dry skin, chapped lips, and altered labs.

The purpose of this study is to compare a lower daily dose of oral isotretinoin against the conventional daily dose in individuals with acne vulgaris.

What the Study Aims to Find Out:

Researchers want to determine if a low-dose regimen can match the effectiveness (efficacy) of the conventional dose while reducing the frequency and severity of side effects (safety).

Study Design:

Participants will be randomly assigned to receive either the low-dose oral isotretinoin or the conventional-dose oral isotretinoin. Researchers will monitor and compare acne clearance rates, patient satisfaction, and any side effects experienced by the participants throughout the treatment period.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

This is a randomized, comparative clinical study designed to evaluate and compare the therapeutic efficacy and safety profile of two different dosing regimens of oral isotretinoin in patients diagnosed with acne vulgaris.

Eligible participants will be allocated into one of two treatment arms:

  1. Experimental Arm (Low Dose): Participants will receive a low daily dose of oral isotretinoin.
  2. Active Comparator Arm (Conventional Dose): Participants will receive the standard conventional daily dose of oral isotretinoin based on standard weight-based guidelines.

Primary Outcome:

Efficacy: Assessed by the percentage reduction in inflammatory and non-inflammatory acne lesions from baseline, as well as The Global Acne grading System(GAGS) Safety and Tolerability: Evaluated through the frequency, type, and severity of clinical adverse effects (e.g., cheilitis, xerosis) and periodic laboratory monitoring (including lipid profiles and liver function tests).

Follow-up visits will be conducted at regular intervals to monitor clinical response, manage side effects, and ensure patient compliance.

Study Type

Interventional

Enrollment (Estimated)

164

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Pakistan
      • Islamabad, Pakistan
        • Pakistan Institute of Medical Sciences(PIMS)
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Both genders
  • Age 18-45 years
  • Patients who are clinically diagnosed with moderate to severe acne vulgaris as per criteria defined in operational definition.

Exclusion Criteria:

  • Patients who are pregnant or lactating
  • Patients with history of endocrine disorders such as PCOS etc. or having drug induced acne
  • Patients on corticosteroid treatment
  • Patients who have hypersensitivity to the isotretinoin
  • Patients who are taking any acne treatment
  • Patients with hyperlipidemia, chronic renal failure or liver failure

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Low Dose Oral Isotretinoin
Participants in this arm will receive a low-dose regimen of oral isotretinoin (e.g., 0.25mg/kg/day for the duration of the treatment period to evaluate its efficacy and safety in acne vulgaris.
Drug: Isotretinoin
Oral isotretinoin capsules administered daily to participants for the treatment of acne vulgaris. This study evaluates two distinct dosing regimens to compare their relative efficacy and safety: 1) Low-Dose Regimen: Participants receive a reduced daily dose (e.g. 0.25 mg/kg/day). 2) Conventional-Dose Regimen: Participants receive the standard weight-based dose (e.g., 0.5 mg/kg/day). Treatment duration, monitoring schedules, and dose adjustments follow protocol specifications.
Other Names:
  • Accutane
  • Roaccutane
Active Comparator: Conventional Dose Oral Isotretinoin
participants in this arm will receive conventional dose of oral isotretinoin (e.g. 0.5 mg/kg/day) for the duration of the treatment period to evaluate its efficacy and safety in acne vulgaris.
Drug: Isotretinoin
Oral isotretinoin capsules administered daily to participants for the treatment of acne vulgaris. This study evaluates two distinct dosing regimens to compare their relative efficacy and safety: 1) Low-Dose Regimen: Participants receive a reduced daily dose (e.g. 0.25 mg/kg/day). 2) Conventional-Dose Regimen: Participants receive the standard weight-based dose (e.g., 0.5 mg/kg/day). Treatment duration, monitoring schedules, and dose adjustments follow protocol specifications.
Other Names:
  • Accutane
  • Roaccutane

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change from baseline in Global Acne Grading System(GAGS)Scoring
Time Frame: 12 weeks
The GAGS is a validated scoring system that calculates acne severity across six specific facial and torso areas (forehead, right cheek, left cheek, nose, chin, and chest/upper back). Each area is assigned a factor based on size, and lesions are graded from 0 (no lesions) to 4 (cystic lesions). The total score ranges from 0 to 44, where 0 is clear and higher scores indicate greater severity. Efficacy will be compared between the low-dose and conventional-dose arms based on the mean reduction in total GAGS score from baseline.
12 weeks
Percentage change in total acne lesion count from baseline
Time Frame: 12 weeks
The total lesion count is calculated by adding the number of inflammatory lesions (papules, pustules, nodules) and non-inflammatory lesions (open and closed comedones) on the face according to GAGS. Efficacy will be compared between the low-dose and conventional-dose arms based on the percentage reduction from day 0.
12 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence and severity of treatment-emergent adverse events (TEAEs)
Time Frame: 12 weeks
Frequency and severity of clinical side effects (such as cheilitis, xerosis/dry skin, conjunctivitis) and laboratory abnormalities (such as elevated liver enzymes or lipid profiles) will be evaluated and compared between the two dosing groups.
12 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Pakistan Institute of Medical Sciences

Investigators

  • Principal Investigator: Dr Nareeman Ur Rehman, MBBS, FCPS, Pakistan Institute of Medical Sciences (PIMS)

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

July 1, 2026

Primary Completion (Estimated)

October 1, 2026

Study Completion (Estimated)

October 1, 2026

Study Registration Dates

First Submitted

June 5, 2026

First Submitted That Met QC Criteria

June 5, 2026

First Posted (Actual)

June 10, 2026

Study Record Updates

Last Update Posted (Actual)

June 10, 2026

Last Update Submitted That Met QC Criteria

June 5, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • PIMS-DERM-ISO-2026-01

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

De-identified individual participant data underlying the principal results of this study (including demographic data, baseline characteristics, efficacy outcomes, and safety parameters) will be made available to ensure transparency and validate study findings.

IPD Sharing Time Frame

Data will become available starting 6 months after the primary publication of the study results and will remain accessible for up to 3 years

IPD Sharing Access Criteria

Anonymized individual participant data will be shared with qualified academic researchers upon reasonable request directed to the corresponding author. Requests must be accompanied by a sound, formal research proposal and require a signed data-use agreement.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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