Reviewed: Wasana KGP, Attanayake AP, Weerarathna TP, Jayatilaka KAPW. Efficacy and safety of [an] herbal drug of Coccinia grandis (Linn.) Voigt in patients with type 2 diabetes mellitus: A double blind randomized placebo controlled clinical trial. Phytomedicine. January 2021;81:153431. doi: 10.1016/j.phymed.2020.153431.
The global increase in the prevalence of type 2 diabetes mellitus (T2DM) has been attributed to several factors, including an aging population and increasingly sedentary lifestyles and poor diets. Hypoglycemic medications can help control blood glucose levels in people with T2DM. However, they can also cause adverse effects. Several phytomedicines have been studied for their use in diabetes management. Ivy gourd (Coccinia grandis, Cucurbitaceae) has been used widely in Sri Lankan traditional herbal medicine to treat diabetes, among other diseases. This randomized, double-blind, placebo-controlled clinical trial investigated the efficacy and safety of an herbal formulation containing ivy gourd leaf extract in people who were newly diagnosed with T2DM.
People with newly diagnosed T2DM who visited the University Medical Clinic at the Teaching Hospital in Karapitiya, Galle, Sri Lanka, were screened for the study. Those with fasting plasma glucose (FPG) concentrations in the range of 126–160 mg/dL and/or glycated hemoglobin (HbA1c) levels of 6.3–7.5% were eligible for inclusion in the study. None of the 158 enrolled participants received any other antidiabetic drugs during the trial. They were given recommendations on physical activity and diet during the study.
During the 12-week study period, researchers scheduled seven study visits. At the baseline visit, socioeconomic and demographic data were collected, and each participant was given a diary to record any adverse effects and daily use of medications. Eligible participants were randomly assigned to the treatment group (n = 79) or placebo group (n = 79) and instructed to take one study capsule daily after lunch for 12 weeks.
Ivy gourd leaves were collected from southern Sri Lanka. An investigator-prepared aqueous ivy gourd leaf extract was freeze-dried to obtain a powder yielding 30% w/w of plant material. Each test capsule contained 500 mg freeze-dried ivy gourd leaf extract powder, and each placebo capsule contained 500 mg corn (Zea mays, Poaceae) starch.
The primary outcome measures were changes in HbA1c, insulin, lipid profiles, fructosamine, and homeostatic model assessment for insulin resistance (HOMA-IR) values. Secondary outcome measures included serum levels of total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and very-low-density lipoprotein cholesterol (VLD-C), as well as atherogenic, cardioprotective, and coronary risk indices. FPG concentrations, renal and liver toxicity parameters, hematological parameters, and blood pressure also were monitored.
Six people in the treatment group were lost to follow-up because of protocol violations, family problems, relocation, or surgery for an accidental injury. In the placebo group, seven people were lost to follow-up due to protocol violations, family problems, relocation, or pregnancy. The final analysis included 73 people in the treatment group and 72 people in the placebo group. All participants had good compliance with the study protocol (they consumed more than 90% of the capsules), and no adverse effects were reported in either group.
After 12 weeks, greater improvements were observed in the treatment group compared with the placebo group in HbA1c, fructosamine, FPG, insulin, HOMA-IR values, triglycerides, and VLD-C (P < 0.001 for all). Safety assessments, blood pressure measures, and anthropometric characteristics did not change significantly in either group throughout the study.
According to the authors, limitations of the study include its short duration, the lack of efficacy comparison between the ivy gourd extract and an active agent, and that the glycemic parameters were not measured with an oral glucose tolerance test.
In this study, the use of the ivy gourd leaf extract for 12 weeks improved glycemic indices and some lipid profile parameters in patients who were newly diagnosed with T2DM. “This dual therapy of action by means of antihyperglycemic activity and improvement of lipid profile together with safety and tolerability of the herbal drug of C. grandis could be beneficial as a new therapeutic approach for the early management of patients with T2DM,” wrote the authors.