Type 2 diabetes mellitus is prevalent especially in Gulf countries and poses serious long-term risks to patients. A multifaceted treatment approach can include nutritional supplements with antioxidant properties such as 5-aminolevulinic acid (5-ALA) with sodium ferrous citrate (SFC). This prospective, randomized, single-blind, placebo-controlled, dose escalating pilot clinical trial assessed the safety of 5-ALA with SFC at doses up to 200 mg 5-ALA/229.42 mg SFC per day in patients living in Bahrain with type 2 diabetes mellitus that was uncontrolled despite the use of one or more antidiabetic drugs. Fifty-three patients (
Type 2 diabetes mellitus is a prevalent chronic disease, which consumes considerable medical resources and has serious long-term clinical consequences. It is currently estimated that 415 million people worldwide have diabetes mellitus [
Treatment for type 2 diabetes mellitus consists of a multifaceted approach implemented in a stepwise fashion, beginning with lifestyle modifications such as improved diet and exercise as the first-line treatment and progressing to oral antidiabetic agents [
5-Aminolevulinic acid (5-ALA) is a natural delta amino acid widely present in nature that plays an important role in living organisms. Trace amounts of 5-ALA exist in common foods such as bananas, spinach, tomatoes, and mushrooms, and larger amounts are found in fermented products such as wine [
Currently, 5-ALA phosphate is approved as a nutritional supplement in Japan, and 5-ALA phosphate in combination with sodium ferrous citrate (SFC) has been approved as a nutritional supplement and marketed in Japan, Philippines, Dubai, Vietnam, Jordan, and Bahrain. 5-ALA hydrochloride is approved in 39 countries and indicated for intraoperative resection of glioma under fluorescence guidance. Clinical studies have shown improved glucose metabolism after 12-week administration of 5-ALA plus sodium ferrous citrate (SFC) as measured by a 2-hour oral glucose tolerance test [
The objective of the current study was to investigate the safety and preliminary efficacy of doses up to 200 mg 5-ALA-SFC in a population of patients with type 2 diabetes mellitus living in Bahrain.
This study was a prospective, randomized, single-blind, placebo-controlled, dose escalating pilot clinical trial. The study protocol was approved by the Research Ethics Committee of the Bahrain Defense Force Royal Medical Services and the National Health Regulatory Agency (NHRA) in the Kingdom of Bahrain and was registered to ClinicalTrials.gov as
Eligible patients were males and females residing in Bahrain, between 20 and 75 years old, who gave written informed consent, were diagnosed with type 2 diabetes mellitus with HbA1c ≥6.5 and ≤10% that was uncontrolled despite the use of one or more antidiabetic drugs, had BMI ≤ 44 kg/m2, sitting BP ≤ 160/100 mmHg, negative sleep apnea screen, and ophthalmological exam within normal limits as judged by the investigator, and otherwise were considered in good health in the opinion of the investigator based on results of medical history, physical exam, and clinical laboratory assessments. Female patients were not pregnant and not breast-feeding and, if of childbearing potential, agreed to use an acceptable method of birth control during the study. Patients were ineligible if they had hepatic dysfunction defined as liver function tests ≥1.5 times the upper limit of normal, renal dysfunction defined as BUN and/or serum creatinine ≥1.5 times the upper limit of normal and/or eGFR <30 mL/min/1.73 m2, history of any life-threatening disease, cardiovascular disease, viral hepatitis, porphyria, or hemochromatosis. Patients also were not enrolled if they had an allergy to ALA, SFC, or any other component of study product, used insulin for management of diabetes, had a hypoglycemic event within the previous 3 months defined as serum glucose levels less than 70 mg/dL, or had a history of sickle cell anemia disease.
Patients were enrolled from 3 clinics at one investigational site at the Bahrain Defense Force Hospital in Manama, Bahrain, from May 2014 to July 2015. After informed consent was obtained, screening procedures were performed including a medical history, physical exam, 12-lead ECG, laboratory assessment, ophthalmologic exam, and screening for sleep apnea. Glucometers and necessary supplies were provided at screening for daily monitoring of glucose levels, and patients were required to record daily glucose levels prior to breakfast and 2 hours after breakfast for at least 7 consecutive days during a run-in phase prior to week 0 randomization visit. Patients continued to monitor daily glucose levels for study purposes prior to breakfast and 2 hours after breakfast until week 12’s visit. These daily measurements were recorded electronically and were downloaded from a flash drive by the site at each visit.
After the run-in period, eligible patients were randomized at week 0 to either 5-ALA-SFC or matching placebo, with two patients allocated to 5-ALA-SFC for every one patient allocated to placebo. Treatment assignments were single-blinded with clinicians aware of the treatment assignment but patients unaware of the treatment they were receiving. Ninety-one patients were screened, and 53 patients were enrolled in the study (Figure
Patient disposition.
Patients returned at week 6 to confirm safety of the 200 mg 5-ALA/229.42 mg SFC total daily dose and then continued dosing for an additional 6 weeks. Dosing ended at week 12, and patients returned at week 14 for a follow-up safety assessment 2 weeks after the final dose of study product. Blood and urine samples for laboratory assessments were collected at each study visit.
The primary endpoint of this study was safety as assessed by incidence of adverse events. Secondary endpoints included incidence of clinically significant abnormalities in laboratory assessments and changes in plasma glucose and glycosylated hemoglobin (HbA1c).
Three subject populations were defined for the purpose of analysis. The safety population included all patients who took at least one dose of study product; the intent-to-treat population (ITT) included all patients who took at least one dose of study product and had at least one postbaseline efficacy evaluation; and the per protocol population (PP) excluded patients with major protocol deviations as determined prior to database lock. Given that the study was conducted in Bahrain, the effect of fasting during the holy month of Ramadan may have impacted plasma glucose related measurements. To assess the magnitude of this impact, patients and visits affected by Ramadan were identified, and analyses of plasma glucose and HbA1c measurements were repeated excluding Ramadan impacted data.
The incidence of adverse events and incidence of clinically significant abnormalities in laboratory tests were compared using Fisher’s Exact Test. In addition, shift tables from baseline were generated for all measured laboratory parameters at week 2, week 4, week 6, week 12, and week 14.
Changes from baseline in parameters of glycemic control (fasting blood glucose, HbA1c, and blood glucose 2 hours after breakfast) were compared between the two treatment groups at weeks 2, 4, 6, and 12 (HbA1c and blood glucose), weeks 8 and 10 (blood glucose only), and week 14 (HbA1c only). A general linear model was constructed with factors for treatment group, clinic, and treatment-by-clinic interaction, and baseline value as covariates. The interaction term was dropped from the model if its
In a post hoc analysis, pairwise comparisons on HbA1c (%) mean change against baseline were tested with paired
Fifty-three patients (53) were enrolled at one study site, with 35 patients randomized to the 5-ALA–SFC group and 18 patients to the placebo group. Overall, the groups were comparable on baseline characteristics, with numerically higher baseline values of total cholesterol, LDL and triglycerides, and waist measurement noted in the 5-ALA-SFC group (Table
Baseline demographics and disease characteristics.
5-ALA-SFC | Placebo | |||
---|---|---|---|---|
| Result | | Result | |
Age (years) | 35 | 52.4 (6.51) | 15 | 51.9 (5.07) |
Sex (male) | 35 | 33 (94.3) | 15 | 13 (86.7) |
Fasting plasma glucose (mg/dL) | 33 | 142.3 (21.87) | 15 | 146.4 (31.35) |
Plasma glucose 2 hrs after meal (mg/dL) | 33 | 189.4 (47.96) | 14 | 191.9 (57.97) |
HbA1c (%) | 35 | 7.8 (0.88) | 15 | 8.0 (0.91) |
Total cholesterol (mg/dL) | 34 | 175.6 (36.14) | 15 | 158.8 (31.27) |
LDL (mg/dL) | 34 | 115.4 (33.87) | 15 | 102.0 (26.37) |
HDL (mg/dL) | 34 | 41.1 (10.80) | 15 | 41.5 (10.25) |
Triglycerides (mg/dL) | 34 | 167.0 (89.17) | 15 | 133.7 (55.28) |
Waist (cm) | 34 | 98.6 (21.12) | 15 | 90.3 (17.35) |
BMI (kg/m2) | 35 | 30.8 (5.72) | 15 | 29.3 (5.44) |
Weight (kg) | 35 | 89.8 (17.02) | 15 | 86.6 (18.89) |
Systolic BP (mmHg) | 35 | 137.7 (16.67) | 15 | 131.3 (15.88) |
Diastolic BP (mmHg) | 35 | 80.7 (10.73) | 15 | 76.2 (8.97) |
Heart rate (b/min) | 24 | 78.4 (11.77) | 9 | 72.1 (8.46) |
All values reported as mean (SD) except sex reported as
There was a numerically higher percentage of patients in the 5-ALA-SFC group experiencing at least one adverse event during the study than the placebo group, but the difference was not statistically significant (45.7% 5-ALA-SFC versus 27.8% placebo;
Summary of adverse events.
5-ALA-SFC | Placebo | |
---|---|---|
Subjects reporting at least one event | 16 (45.7%) | 5 (27.8%) |
Subjects reporting at least one related event | 7 (20%) | 3 (16.7%) |
Subjects reporting at least one severe event | 0 | 0 |
Subjects reporting at least one event leading to study discontinuation | 6 (17.1%) | 1 (5.6%) |
A cumulative summary of adverse events reported during the dose escalation to 200 mg 5-ALA-SFC is presented in Table
Cumulative summary of treatment emergent adverse events over time.
Week 2 (100 mg 5-ALA-SFC) | Week 4 (150 mg 5-ALA-SFC) | Week 6 (200 mg 5-ALA-SFC) | Week 12 (200 mg 5-ALA-SFC) | Week 12 (Placebo) | |
---|---|---|---|---|---|
Subjects reporting at least one event | 6 (17.1%) | 14 (40.0%) | 15 (42.9%) | 16 (45.7%) | 5 (27.8%) |
| |||||
Abdominal distension | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Abdominal pain upper | 1 (2.9%) | 2 (5.7%) | 2 (5.7%) | 2 (5.7%) | 0 |
Alopecia | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Blood glucose increased | 0 | 0 | 1 (2.9%) | 1 (2.9%) | 0 |
Constipation | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Cough | 1 (2.9%) | 2 (5.7%) | 2 (5.7%) | 2 (5.7%) | 0 |
Decreased appetite | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Diarrhea | 2 (5.7%) | 2 (5.7%) | 2 (5.7%) | 2 (5.7%) | 2 (11.1%) |
Dyspepsia | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 1 (5.6%) |
Erectile dysfunction | 0 | 0 | 1 (2.9%) | 1 (2.9%) | 0 |
Fatigue | 0 | 1 (2.9%) | 2 (5.7%) | 2 (5.7%) | 0 |
Feces discolored | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Feces hard | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Gastrointestinal disorder | 0 | 0 | 1 (2.9%) | 1 (2.9%) | 0 |
Groin pain | 0 | 0 | 0 | 0 | 1 (5.6%) |
Headache | 0 | 1 (2.9%) | 1 (2.9%) | 2 (5.7%) | 1 (5.6%) |
Hypoglycemia | 0 | 0 | 0 | 1 (2.9%) | 1 (5.6%) |
Hypokalemia | 0 | 0 | 0 | 0 | 1 (5.6%) |
Nasal abscess | 0 | 0 | 0 | 1 (2.9%) | 0 |
Nasal congestion | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Nausea | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Palpitations | 0 | 0 | 1 (2.95) | 1 (2.9%) | 0 |
Pyrexia | 0 | 1 (2.9%) | 1 (2.9%) | 1 (2.9%) | 0 |
Cumulative adverse events reported at each visit.
Analysis of hematology, biochemistry, and urinalysis laboratory tests did not reveal any clinically significant changes from baseline during the study. Mean change from baseline for laboratory assessments of interest are shown in Table
Laboratory parameters at week 6 and week 12.
5-ALA-SFC | Placebo | |||||
---|---|---|---|---|---|---|
| Mean | Change from baseline | | Mean | Change from baseline | |
Total cholesterol (mg/dL) | ||||||
Week 6 | 27 | 166.9 | −5.2 (3.7) | 13 | 150.3 | −7.6 (5.5) |
Week 12 | 25 | 181.4 | 6.8 (3.5) | 13 | 160.2 | −0.1 (5.0) |
| ||||||
LDL cholesterol (mg/dL) | ||||||
Week 6 | 27 | 109.4 | −2.9 (3.2) | 13 | 92.4 | −11.8 (4.7) |
Week 12 | 25 | 121.4 | 7.6 (3.3) | 13 | 101.2 | −4.0 (4.6) |
| ||||||
HDL cholesterol (mg/dL) | ||||||
Week 6 | 27 | 40.2 | −0.8 (1.0) | 13 | 37.0 | −1.6 (1.4) |
Week 12 | 25 | 41.9 | 0.5 (1.0) | 13 | 37.4 | −1.1 (1.4) |
| ||||||
Triglycerides (mg/dL) | ||||||
Week 6 | 27 | 156.6 | −1.3 (14.6) | 13 | 150.4 | 4.5 (21.1) |
Week 12 | 25 | 163.9 | 3.2 (11.1) | 13 | 159.0 | 11.9 (15.4) |
| ||||||
BUN (mg/dL) | ||||||
Week 6 | 25 | 14.05 | 1.19 (0.573) | 11 | 13.42 | −0.43 (0.665) |
Week 12 | 26 | 13.87 | 1.28 (0.606) | 12 | 13.00 | −0.54 (0.816) |
| ||||||
Serum creatinine (mg/dL) | ||||||
Week 6 | 28 | 0.96 | 0.01 (0.021) | 13 | 1.04 | −0.01 (0.023) |
Week 12 | 26 | 0.96 | −0.00 (0.016) | 13 | 1.06 | 0.01 (0.026) |
| ||||||
Ferritin (mg/dL) | ||||||
Week 6 | 26 | 169.03 | 31.12 (9.480) | 12 | 136.48 | −12.59 (9.033) |
Week 12 | 22 | 148.71 | 16.64 (11.289) | 12 | 137.54 | −11.53 (14.456) |
| ||||||
Serum iron (mg/dL) | ||||||
Week 6 | 27 | 18.16 | 0.87 (1.330) | 12 | 16.14 | −2.27 (1.502) |
Week 12 | 22 | 17.73 | 1.41 (1.409) | 12 | 16.74 | −1.67 (1.083) |
| ||||||
Transferrin saturation (%) | ||||||
Week 6 | 25 | 31.38 | 3.77 (2.960) | 12 | 28.48 | −3.43 (2.562) |
Week 12 | 21 | 29.93 | 3.37 (2.638) | 12 | 29.55 | −2.36 (1.753) |
Patients in both groups experienced a decrease in weight from baseline to week 12, with a decrease of −0.2 kg in the 5-ALA group and −0.8 kg in the placebo group (
Mean and change from baseline HbA1c levels are presented in Table
Change in mean HbA1c during dosing period (ITT and PP populations).
5-ALA-SFC | Placebo | |||||
---|---|---|---|---|---|---|
| Mean | Change from baseline | | Mean | Change from baseline | |
Intent-to-treat population | ||||||
Week 2 | 32 | 7.6 | −0.2 | 13 | 7.4 | −0.5 |
Week 4 | 30 | 7.5 | −0.3 | 13 | 7.3 | −0.5 |
Week 6 | 28 | 7.3 | −0.4 | 13 | 7.2 | −0.6 |
Week 12 | 25 | 7.1 | −0.7 | 13 | 7.3 | −0.5 (0.2) |
| ||||||
Per protocol population | ||||||
Week 2 | 15 | 7.3 | −0.3 | 6 | 7.6 | −0.3 (0.2) |
Week 4 | 15 | 7.1 | −0.4 | 7 | 7.3 | −0.5 (0.2) |
Week 6 | 14 | 7.1 | −0.4 | 7 | 7.2 | −0.6 (0.2) |
Week 12 | 14 | 6.8 | −0.8 | 7 | 7.3 | −0.5 (0.3) |
Changes in mean HbA1c during dosing period ((a) ITT population, (b) PP population).
Mean and change from baseline for fasting plasma glucose and glucose 2 hours after breakfast are presented in Table
Mean and change from baseline in fasting plasma glucose and plasma glucose 2 hours after breakfast (ITT population).
5-ALA-SFC | Placebo | |||||
---|---|---|---|---|---|---|
| Mean | Change from baseline | | Mean | Change from baseline | |
Fasting plasma glucose (mg/dL) | ||||||
Week 2 | 33 | 145.1 | 2.3 (3.4) | 14 | 138.4 | −7.3 (5.2) |
Week 4 | 30 | 142.1 | −0.2 (4.9) | 14 | 145.6 | −0.8 (7.2) |
Week 6 | 27 | 138.0 | −4.8 (3.2) | 13 | 132.4 | −9.2 (4.7) |
Week 8 | 22 | 135.8 | −4.5 (4.0) | 12 | 142.7 | −1.0 (5.5) |
Week 10 | 23 | 140.3 | −0.9 (5.6) | 12 | 143.1 | −0.9 (7.8) |
Week 12 | 22 | 139.3 | −3.0 (4.4) | 12 | 139.5 | −4.2 (5.9) |
| ||||||
Plasma glucose 2 hours after meal (mg/dL) | ||||||
Week 2 | 33 | 189.6 | −0.2 (5.1) | 14 | 166.3 | −26.5 (7.8) |
Week 4 | 30 | 175.7 | −12.9 (6.1) | 12 | 173.9 | −18.8 (9.9) |
Week 6 | 27 | 173.4 | −14.5 (5.4) | 13 | 158.5 | −27.4 (7.8) |
Week 8 | 20 | 176.2 | −5.6 (5.6) | 11 | 155.0 | −30.5 (11.2) |
Week 10 | 20 | 175.1 | −10.3 (10.5) | 12 | 181.2 | −7.6 (13.5) |
Week 12 | 21 | 175.0 | −8.5 (9.8) | 10 | 154.3 | −33.0 (14.2) |
Post hoc additional analyses were conducted to assess the magnitude of HbA1c change from baseline for a variety of subgroups based on the class of concomitant antidiabetic medications use. HbA1c (%) change from baseline at each study visit was analyzed by class of antidiabetic drugs such as biguanides (BG), dipeptidyl peptidase-4 inhibitors (DPP-4), Sulphonylureas (SU), thiazolidinediones (TZD), and Combo (one subject taking a BG + DPP-4 and one subject taking a BG + SU). Among patients taking SU antidiabetic drugs, a gradual decline of HbA1c value was observed from week 2 through week 14 in the 5-ALA-SFC group (−0.25 (week 2), −0.37 (week 4), −0.49 (week 6), −0.95 (week 12), and −1.21 (week 14)), whereas such a trend was not seen in the placebo group (−0.64 (week 2), −0.58 (week 4), −0.75 (week 6), −0.63 (week 12), and −0.87 (week 14)). The result of analysis of HbA1c change against baseline using paired
The results of the current study support that administration of the nutritional supplement 5-ALA-SFC up to doses of 200 mg 5-ALA/229.42 mg SFC per day is safe in patients with type 2 diabetes mellitus taking oral antidiabetic medications. Use of nutritional supplements is widespread in patients with diabetes [
Hypoglycemia could be a concern with use of a nutritional supplement in conjunction with oral antidiabetic agents, but there was no difference in hypoglycemia between patients receiving 5-ALA and placebo, with one patient self-reporting hypoglycemia in each treatment group. These results are consistent with a study conducted in Japan assessing the safety of 5-ALA-SFC in 45 patients with diabetes treated with oral antidiabetic medications, which showed doses of 15 mg and 50 mg of 5-ALA-SFC to be well tolerated by patients [
This pilot study also provided an opportunity for exploratory evaluation of the effect of 5-ALA-SFC on glycemic control in patients with type 2 diabetes mellitus, although it was not powered to detect differences in any of the efficacy measures. The study demonstrated that the 5-ALA group had constant gradual decrease in HbA1c over 12 weeks during study drug dosing, while the placebo group showed an initial decrease but rebounded after 6 weeks. HbA1c reflects glycemic control over the previous several months [
Daily blood glucose measurements were collected in the study by patients prior to breakfast and 2 hours after breakfast through home use of a glucometer. Results of the glucose analyses did not reveal any sustained statistically significant differences between the two treatment groups. Previous clinical studies however have shown significantly reduced blood glucose levels, using a 2-hour oral glucose tolerance test (OGTT). In a study conducted in Hawaii in 154 patients with HbA1c between 5.8 and 7.0%, significant decreases in 2-hour OGTT were seen after 12 weeks of 15 mg as well as 50 mg of 5-ALA. The reduction was greater in patients with 2-hour OGTT results at baseline ≥140 mg/kL [
The changes in glycemic control noted in the placebo group during the first 6 weeks of the study suggest that blinded study drug dosing may have mediated a change in patient behaviour that improved patient compliance with diet, exercise, and/or antidiabetic medications, which could have led to this improvement in glycemic control. This finding supports the stepwise treatment recommendations beginning with lifestyle changes including dietary modifications.
Clinical research studies support the development of new therapeutic options, and country-specific studies are important to generate data in a local population. The number of research studies conducted in the Middle East is increasing, and local ethical guidelines are being implemented on a country-specific basis [
There are several limitations in the current study. The primary objective was to assess safety of escalating doses of 5 ALA-SFC; therefore, the study was not powered to detect differences in efficacy. Glucose measurements of fasting and 2 hours after breakfast were calculated from data collected via glucometer, which relies heavily on patient compliance with daily monitoring and correct operation of the device. The study population enrolled in this study had a wide range of weight (BMI (21.0–43.9 kg/m2)) and baseline glucose control (HbA1c: 6.6–10.2%), with the potential for variable efficacy responses across this spectrum.
The patients in the ITT population who were not in compliance with dosing and daily self-monitoring of glucose were excluded, and the PP population was formed with the rest of the patients in compliance. It seems that the PP population represents the patients most compliant to study procedures including dosing and the reliable dosing would be expected to improve HbA1c levels.
In the groups of patients taking SU antidiabetic drugs, the results of analysis calculated by paired
This study in patients with type 2 diabetes mellitus living in Bahrain supports that use of 5-ALA-SFC up to 200 mg per day taken as 2 divided doses is safe in patients taking concomitant oral antidiabetic medications. 5-ALA-SFC may offer benefits in the diabetic population, and larger studies enrolling a greater number of patients over longer periods of time are required to further define the effect of 5-ALA-SFC on glycemic control in this population.
5-Aminolevulinic acid
Sodium ferrous citrate
Type 2 diabetes mellitus
Reactive oxygen species
Body mass index
Blood pressure
Blood urea nitrogen
Estimated glomerular filtration rate
Glycohemoglobin A1c
Intent-to-treat population
Per protocol population
Low density lipoprotein
Oral glucose tolerance test.
The authors declare that they have no competing interests.
This study was sponsored by SBI Pharmaceuticals Co., Ltd., and was conducted with the support of DZS Clinical Services as the Contract Research Organization overseeing study monitoring and management, data management and analysis, medical monitoring, and technical writing including support for manuscript preparation. The authors express special thanks to Ms. Maria Paluselli for her excellent medical writing assistance.