Phase IIb and III Safety and Efficacy Study Chlorin E6 Gel Photodynamic Therapy for Diabetic Foot Ulcers:

This is a single-centre, open-label, randomized Phase IIb and Phase III clinical study designed to evaluate the safety, tolerability, and efficacy of Chlorin E6 gel as a photosensitizing agent in the management of diabetic foot ulcers (DFU) using Photodynamic Therapy (PDT).

Eligible participants are adults (≥18 years) with a documented diagnosis of diabetes and chronic foot ulceration present for at least 4 weeks. In Phase IIb, 30 participants were enrolled; Phase III will include 300 participants.

The investigational product, Chlorin E6 gel (1% W/V, 1.0 mg/cm²), is applied locally to the ulcer. After 30 minutes, the ulcer is washed with saline and illuminated with red light (660-670 nm) at a dose of 100 J/cm² for 11 minutes. If required, a second illumination is performed. Standard of care (SOC) management-including wound debridement, targeted antibiotics, and optimized glycemic control-is provided to all participants.

Primary objectives are to assess safety and efficacy of Chlorin E6-mediated PDT, evaluate ulcer healing (size and depth reduction), compare healing rates with SOC alone, and determine bacterial eradication. Secondary objectives include recurrence rates and reduction in amputations within 6 months.

Endpoints include solicited local/systemic adverse events (AEs), unsolicited AEs, serious adverse events (SAEs), abnormal laboratory values, wound culture results, and healing rates (>15% at 1 week or >50% at 1 month).

The study lasted 3 months per participant in Phase IIb (completed) and 6 months per participant in Phase III, was started in March 2026.

Inclusion criteria

• Patients with diagnosis of Diabetes mellitus, with diabetic foot ulcer.
• Males and females subject of age 18 years and above.
• HbA1c of less than 12% and random blood sugars of less than 350 mg/dl.
• Vitally stable patient with no clinical signs of sepsis, a qSOFA (quick Sepsis-Related Organ Failure Assessment) score of <2.
• ABI (Ankle Brachial Index) 0.7 to 1.2.
• Lower extremity ulcer of more than 30 days duration and less than 2 years duration.
• Total wound surface area between 0.5 to 20 cm.
• Deep wounds extending up to muscles (University of Texas Grade & Stage 1A, 1B, 2A & 2B) will be included.
• Patients giving written informed consent to participate in the study after a full understanding of the implications and constraints of the study protocol.
• Understand the content of the ICF, and voluntarily sign the ICF (If the participant is unable to sign the ICF on his/her own due to illiteracy, an impartial witness is needed).
• The subject can understand the research process and is willing and able to comply with all research proposals and other requirements of the study.
• Able to cooperate to complete the scheduled follow-ups till the end of the study

Exclusion criteria

• The vital signs or physical examination are clinically significantly abnormal as determined by the investigators in screening.
• A history of severe allergy (including drugs, vaccines, and foods) or allergy to any component of the experimental product.
• Subjects diagnosed with a serious disease, congenital malformation or chronic disease (including but not limited to serious: respiratory disease, cardiovascular disease, serious cerebrovascular disease, kidney disease, serious or uncontrollable diabetes, autoimmune disease, thrombocytopenic purpura, thalassemia, malignant tumor, hereditary allergic constitution, etc.) that may interfere with the conduct or completion of the study;
• Participating in or planning to participate in other clinical trials (drugs or vaccines) within 3 months prior to participating in this study;
• Other circumstances considered by the investigator as inappropriate to participate in the study.
• Vitally unstable patients with clinical signs and symptoms of sepsis, qSOFA score ≥2.
• More than 2 ulcers in the foot and leg.
• Deep wounds extending into bone (UoT Criteria any Grade stage C & D, Grade 3).
• Subjects with moderate to severe obstruction on ABI (<0.7 or >1.3).
• Patients with HbA1c more than 12% and random blood sugar of more than 350 mg /dl.
• Subjects with evidence of cardiac disease or heart failure on ECG or echocardiography
• Patients with eGFR (Estimated Glomerular Filtration Rate) of less than 60 ml/min/1.73 m2.
• Pregnant or breast-feeding females or women of childbearing potential not using contraception.
• Hypersensitivity to investigational product/Chlorophyll-driven compounds.
• Diagnosed case of porphyria.
• Ophthalmological disease requiring slit-lamp examination or Yag-laser within the next 30 days or anti-VEGF therapy/injection.
• Patients who do not give written informed consent
• Subjects unable or unwilling to meet protocol requirements.
• Ulcer of non-diabetic etiology, such as venous, arterial, and burn wounds
• Ulcer is less than 3 cm in distance from any other ulcer on the same extremity.
• Ulcer presents with any of the following: osteomyelitis, exposed bone or gangrene.
• Ulcer surface area has decreased > 40% between screening and at randomization (visit 1) as assessed by the imaging system
• Has medically documented history of HIV
• Has severe protein malnutrition as defined by Serum Albumin < 2.5 g/dL.
• Has serum aspartate aminotransferase (AST, SGOT, GOT) or serum alanine aminotransferase (ALT, SGPT, GPT) levels greater than twice the upper limit of normal
• Has a medically documented or self-reported history, within the previous 12 months from date of screening visit, of alcohol or substance abuse.
• Has received previous treatment with the following during the 60 days prior to screening: immunosuppressive agents, radiation, chemotherapy, growth factors at the site of the Ulcer, split- or full-thickness skin graft at the site of the Ulcer, biologically active (or engineered) cellular or acellular product(s) at the site of the study ulcer, investigational drug or device
• Has ESR > 70 mm/h and CRP > 100 mg/L at time of screening