Efficacy and Safety of a Botanical Total Coumarin (TC) Cream in Treating Patients With Psoriasis Vulgaris (PLANTCOAT-III) (PLANTCOAT-III)

A Double-blind, Randomized, Placebo-controlled, Parallel-controlled, Multi-center Phase III Clinical Trial to Evaluate the Efficacy and Safety of a Botanical Total Coumarin Cream (TC Cream) in Treating Patients With Psoriasis Vulgaris

The goal of this clinical trial is to learn if a botanical Total Coumarin topical cream (TC Cream) works to treat psoriasis in adults. It will also learn about the safety of the topical TC Cream. The main questions it aims to answer are:

• Does TC Cream improve the psoriasis disease symptoms?
• What medical problems do participants have when applying TC Cream?
• Does TC Cream improve the quality of life of psoriasis patients? Researchers will compare TC Cream to a placebo cream (a look-alike cream that contains no active drug) to see if TC Cream works to treat psoriasis.

Participants will:

• Topically apply the TC Cream or a placebo cream twice daily every day to affected skin for 8 weeks
• Visit the clinic once every 2 weeks for checkups and tests
• Keep a diary of their symptoms and their diseased skin conditions during the application of the topical cream

Study Overview

• Status: Recruiting
• Conditions: Psoriasis Vulgaris; Phase III; Topical Administration
• Intervention / Treatment: Drug: Total coumarin (TC) cream; Drug: Vehicle cream

Detailed Description

Participants are put into one of two groups: 1. TC Cream group: receives the cream with the active botanical ingredient; 2. Placebo group: receives a look-alike cream with no active ingredient. Participants will apply the assigned cream twice daily (morning and evening) to psoriasis-affected areas for 8 weeks and will come to the clinic every 2 weeks for checkups and study tests. Doctors will check your skin, measure psoriasis severity, and ask about symptoms and any side effects. The study aims to decide whether TC Cream is a safe, effective topical option for psoriasis and whether it can also help people feel better in daily life.

• Study Type: Interventional
• Enrollment (Estimated): 300
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Jiang Yang, MSc, PhD; Phone Number: +1-(608)-772-1251; Email: terence0731@gmail.com

Study Locations

• United States
  • New York
    • New York, New York, United States, 11203
      • Recruiting
      • Department of Dermatology, SUNY Downstate Health Sciences University
      • Contact: Wei-Li Lee, PhD; Phone Number: +1-(718) 270-1910; Email: Wei-Li.Lee@downstate.edu
      • Principal Investigator: Sharon Glick, MD
      • Sub-Investigator: Edward Heilman, MD
      • Sub-Investigator: Soodeh Kebir, MD
      • Sub-Investigator: Wei-Li Lee, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age of 18-70 years old. Both men and women, and members of all races and ethnic groups
• Consistent with the diagnostic criteria of stable phase psoriasis vulgaris, and have at least two target lesions suitable for evaluation
• Women of childbearing age must be using birth control strategies defined by one of the following: 1) a barrier method (condom) and/or 2) oral contraceptives, during the 8-week study period.
• ISGA score ≥ 2 (at least mild severity)
• BSA (stable stage group): 1%≤ to ≤20%
• Signed a written informed consent document
• No additional exposure to the sun

Exclusion Criteria:

• Subjects in pregnancy, preparing for pregnancy, or breastfeeding
• History of hyperergic or photosensitivity
• History of complicated cardiovascular diseases, cerebrovascular diseases, severe primary diseases of the hepatic, kidney, and hematopoietic system, or patients with psychiatric disorders
• History of photosensitive diseases such as porphyria, chronic actinic dermatitis, Xeroderma pigmentosa

• Within 4 weeks prior to randomization, patients have taken treatment with the following approved or investigational psoriasis therapies on the target lesions:

  • Topical treatments
  • PUVA, UVB, or Grenz ray therapy.
  • Any systemic treatments other than biologicals with a possible effect on psoriasis (e.g., corticosteroids, vitamin D analogues, hydroxycarbamide, azathioprine, methotrexate, cyclosporine, other immunosuppressants).
  • Any types of other investigational therapies for psoriasis
• Within 3 months prior to randomizations, patients have taken systemic treatments with retinoids or biological therapies (marketed or otherwise) with a possible effect on psoriasis (e.g., alefacept, efalizumab, etanercept, infliximab).
• Planned initiation of, or changes to, concomitant medications that could affect psoriasis (e.g., beta blockers, anti-malaria drugs, lithium) during the double-blind phase of the study.
• History of allergic reactions attributed to compounds of similar chemical or biologic compositions to Coumarins.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Total coumarin (TC) cream (10%); Twice a day (BID) for 8 weeks	Drug: Total coumarin (TC) cream; A well-characterized botanical drug for the topical treatment of psoriasis vulgaris. The drug has been approved by the NMPA in China and has obtained an NDA following multiple clinical trials spanning phases I-III in large cohorts. A previous phase IIb clinical trial has been completed in the U.S.; Other Names: TC Cream
Placebo Comparator: Vehicle cream; Twice a day (BID) for 8 weeks	Drug: Vehicle cream; The same cream formulation as the active comparator TC Cream except that the vehicle cream does not contain active pharmaceutical ingredients; Other Names: Vehicle; Placebo cream

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Investigator's Global Assessment (IGA) (5-point scale)	0-4 scale to measure the global severity of psoriasis. 0-Clear, 1-Almost Clear, 2-Mild, 3-Moderate, 4-Severe	Baseline, weeks 2, 4, 6, and 8; week 12 (4 weeks after drug withdrawal)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Investigator's Static Global Assessment (ISGA) (6-point scale)	A validated, physician-reported outcome measure used to evaluate the overall severity of psoriasis at a single time point	Baseline, weeks 2, 4, 6, and 8; week 12 (4 weeks after withdrawal)
Psoriasis Area and Severity Index (PASI) Scores and PASI 75 percentage	PASI 75 represents a 75% or greater reduction in the Psoriasis Area and Severity Index (PASI) score from baseline, indicating significant clinical improvement.	Baseline, weeks 2, 4, 6, and 8; week 12 (4 weeks after withdrawal)
Itch Numeric Rating Scale (NRS) (11-point scale)	NRS is a validated, 11-point patient-reported tool (0 = "no itch", 10 = "worst imaginable itch") used to measure daily peak itch intensity over the past 24 hours, as a quick, self-administered assessment of psoriasis severity.	Baseline, weeks 2, 4, 6, and 8; week 12 (4 weeks after withdrawal)
Dermatology Life Quality Index (DLQI) scores	The Dermatology Life Quality Index (DLQI) is a validated 10-question questionnaire (0-30 range) that assesses the impact of psoriasis on a patient's life; higher scores indicate greater impairment. Scores are banded to interpret severity: 0-1 (no effect), 2-5 (small effect), 6-10 (moderate effect), 11-20 (very large effect), and 21-30 (extremely large effect).	Baseline and 8 weeks
Psoriasis Disability Index questionnaire (PDI) scores	The Psoriasis Disability Index (PDI) is a 15-question, self-administered questionnaire that assesses the impact of psoriasis on daily life; total scores range from 0 to 45 (higher scores indicate greater impairment). It measures five categories: daily activities, work/school, personal relationships, leisure, and treatment. Each of the 15 questions is typically scored from 0 to 3 (0 = not at all, 1 = a little, 2 = a lot, 3 = very much).	Baseline and 8 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of patients with adverse events and severe adverse events related to treatment		During the entire 12 weeks of study
Urinalysis laboratory assessments for patients with drug-related changes in clinical laboratory results from baseline	White blood cells (number/L), red blood cells (number/L), and urine protein (mg/dL). WBC reflects the body's immune activity-high values commonly suggest infection or inflammation, while low values can occur with viral illness, medication effects, bone-marrow suppression, or severe systemic illness. RBC reflects the blood's oxygen-carrying capacity-low counts point toward anemia, whereas high counts may indicate dehydration/hemoconcentration, chronic low oxygen states, or a marrow disorder. Urine protein indicates protein leakage into the urine, which can be transient (exercise, fever, dehydration, UTI), but if persistent, it suggests kidney injury.	Baseline and 8 weeks
Hematology and coagulation laboratory assessments for patients with drug-related changes in clinical laboratory results from baseline	White blood cells (WBC, number/L), red blood cells (RBC, number/L), hemoglobin (g/L), platelets ( number/L), complete blood count (CBC, number/L), prothrombin time (sec), partial thromboplastin time (sec). White blood cells indicate immune and inflammatory activity. Red blood cells and hemoglobin reflect oxygen-carrying capacity and are used to detect and characterize anemia or polycythemia/hemoconcentration. Platelets reflect clotting potential and bleeding/thrombosis risk. A complete blood count is a combined panel that reports WBC, RBC/hemoglobin, and platelets to screen for infection, anemia, and hematologic disorders. Prothrombin time assesses the extrinsic coagulation pathway and is used to evaluate bleeding risk and liver function. Partial thromboplastin time assesses the intrinsic pathway and is used to evaluate bleeding disorders and to monitor unfractionated heparin; prolongation suggests factor deficiencies, inhibitors, or anticoagulant effects.	Baseline and 8 weeks
Systolic/diastolic blood pressure assessments for patients with drug-related changes in physical examination from baseline related to treatment	systolic pressure (mmHg); diastolic pressure (mmHg). Systolic/diastolic blood pressure (BP) assessment measures the peak arterial pressure during heart contraction (systolic) and the resting pressure between beats (diastolic) and is a core screening and monitoring tool for cardiovascular risk.	Baseline and 8 weeks
Pulse rate assessments for patients with drug-related changes in physical examination from baseline related to treatment	Beats/minute. Pulse rate is the number of heartbeats per minute felt at an artery and provides a quick assessment of cardiovascular status	Baseline and 8 weeks
Respiration rate assessments for patients with drug-related changes in physical examination from baseline related to treatment	Breaths per minute. Respiration rate is the number of breaths per minute and is a sensitive vital sign for respiratory and systemic illness.	Baseline and 8 weeks
Body temperature assessments for patients with drug-related changes in physical examination from baseline related to treatment	Body temperature (degree Celsius)	Baseline and 8 weeks
Laboratory assessments of liver functions for patients with drug-related changes in clinical laboratory results from baseline	Alanine aminotransferase (ALT, U/L), aspartate aminotransferase (AST, U/L). These are liver enzymes indicating liver damage.	Baseline and 8 weeks
Laboratory assessments of renal functions for patients with drug-related changes in clinical laboratory results from baseline	Blood urea nitrogen (BUN, mg/dL), creatinine (CR, mg/dL ); BUN dictates the urea concentration in the blood. Creatinine is the by-product of muscle breakdown.	Baseline and 8 weeks
Assessments of PR/PQ intervals, QRS duration, and QT intervals by ECG for patients with drug-related changes from baseline	ECG intervals are measured in milliseconds (ms) by counting small boxes on the ECG grid and converting to time. PR interval: The time from the start of the P wave to the start of the QRS complex, and it reflects how long the electrical signal takes to travel from the atria through the AV node into the ventricles. PQ interval: Often used interchangeably with PR interval in clinical practice. QRS duration: The width (time length) of the QRS complex, which tells how long ventricular depolarization takes. QT interval: The time from the start of the QRS to the end of the T wave, which is the total time for the ventricles to depolarize and repolarize.	Baseline and 8 weeks

Collaborators and Investigators

• Sponsor: Psoriasis Research Institute of Guangzhou
• Investigators: Study Chair: Liping Yang, MD, Psoriasis Research Institute of Guangzhou; Study Director: Jiang Yang, MSc, PhD, Psoriasis Research Institute of Guangzhou; Principal Investigator: Sharon A Glick, MD, Department of Dermatology, SUNY Downstate Health Sciences University; Principal Investigator: Jiang Yang, MSc, PhD, Psoriasis Research Institute of Guangzhou

Publications and helpful links

Helpful Links

• An abstract on the completed phase IIb U.S. clinical trial of total coumarin cream referenced in Journal of Investigative Dermatology
• An abstract on the completed phase IIb U.S. clinical trial of total coumarin cream referenced in Journal of the American Academy of Dermatology

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): June 30, 2028

Study Registration Dates

• First Submitted: February 9, 2026
• First Submitted That Met QC Criteria: February 15, 2026
• First Posted (Actual): February 23, 2026

Study Record Updates

• Last Update Posted (Actual): February 23, 2026
• Last Update Submitted That Met QC Criteria: February 15, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Psoriasis; Topical cream; Botanical drug; FDA IND; NMPA approval
• Additional Relevant MeSH Terms: Skin Diseases, Papulosquamous; Skin Diseases; Skin and Connective Tissue Diseases; Psoriasis
• Other Study ID Numbers: 105883-4 v.02

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No