A Double-Blind, Placebo-Controlled Study of Fermented Deglycyrrhizinated Licorice Extract

Helwan University

Status and phase: Completed; Phase 2

Conditions: Diabetic Polyneuropathy

Treatments: Dietary Supplement: Non-fermented Deglycyrrhizinated Licorice; Drug: Fermented Deglycyrrhizinated Licorice

Study type: Interventional

Funder types: Other

Identifiers

NCT07148804

6016A

Details and patient eligibility

About

This double-blind, placebo-controlled study evaluated the efficacy of oral α-amylase enzyme replacement therapy in treating early-stage diabetic polyneuropathy (DPN). The study was conducted at Al-Azhar University Hospitals with 83 diabetic patients randomized to receive either fermented deglycyrrhizinated licorice extract (FDGL) containing α-amylase enzyme (2500 IU/gm) or placebo for 6 months. Primary outcomes measured improvements in nerve conduction velocity and vibration perception threshold.

Full description

Diabetes mellitus complications continue to develop despite optimal glycemic control with insulin. Recent studies suggest that serum amylase deficiency correlates with the severity of diabetic complications. This study hypothesizes that α-amylase enzyme deficiency represents an enzymatic defect in the cascade between activated insulin receptors and mitochondrial energy liberation, contributing to diabetic complications.

α-amylase is a glycolytic enzyme that undergoes entero-pancreatic circulation and is proposed to be a precursor to key phosphorylating enzymes (glycogen phosphorylase, glucokinase, and hexokinase) essential for glycolysis. Supplementation with α-amylase may restore normal carbohydrate metabolism and prevent diabetic complications.

The study drug is a formulation rich in α-amylase enzyme prepared from fermented deglycyrrhizinated licorice root extract, also containing acid-lipase enzyme and naturally occurring flavonoids. The intervention was administered as 500mg capsules twice daily, one hour before meals, for 6 months alongside regular antidiabetic medications.

Enrollment: 83 patients

Sex: All

Ages: 15 to 65 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Confirmed diagnosis of Type 1 or Type 2 diabetes mellitus
• Age between 15 and 65 years
• Diabetes duration of 1-5 years
• Body Mass Index (BMI) < 30 kg/m²
• HbA1c < 9%
• Serum creatinine < 2mg/dL
• Serum α-amylase < 45 IU/L (reference range: 28-100 IU/L)
• Vibration Perception Threshold (VPT) > 15V
• Absence of clinical symptoms of diabetic polyneuropathy

Exclusion criteria

• Treatment with medications that might influence nerve function (antiepileptic agents, tricyclic antidepressants, sympathomimetic agents)
• Presence of myopathies
• Presence of neuropathies from other causes
• Presence of malignancies
• Clinical symptoms of diabetic polyneuropathy
• Inability to comply with study protocol

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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83 participants in 2 patient groups, including a placebo group

Fermented Deglycyrrhizinated Licorice

Active Comparator group

Description:

Oral capsules containing 500 mg of fermented deglycyrrhizinated licorice root extract standardized to 2500 IU/gm of α-amylase enzyme and naturally occurring flavonoids and acid-lipase. Administered twice daily (1000 mg/day).

Treatment:

Drug: Fermented Deglycyrrhizinated Licorice

Placebo Comparator

Placebo Comparator group

Description:

500 mg non-fermented deglycyrrhizinated licorice root extract capsules, matching FDGL in appearance, color, weight, and excipients. Administered twice daily.

Treatment:

Dietary Supplement: Non-fermented Deglycyrrhizinated Licorice