Background: KBMSI-2, which is the herbal formular consisted of Ginseng Radix Rubra, Dioscorea tenuipes, Cornus officinalis Sieb. Et Zucc, Lycium Chinese Mill, Curcuma logna Linn, Honey, improved the erectile function by preserving the smooth muscle content and inhibiting the fibrosis of the corpus cavernosum in STZ-induced diabetic rat model. In this study, the researchers investigated the efficacy and safety of the herbal formula (KBMSI-2) in the treatment of ED.

Material and Methods: Patients were instructed to take investigational products (KBMSI-2 6g or placebo) twice a day for 8 weeks at least 1 hour after food intake. The primary efficacy variable was the change in the EF domain scores of the IIEF questionnaire from baseline. Secondary efficacy measures included change in all domain scores of the IIEF from baseline, change in question 2 and 3 of the SEP2,3, from baseline.

Inclusion criteria were as follows:

• men with history of ED for at least 6 months according to the National Institutes of Health (NIH) Consensus Statement (inability to attain and/or maintain penile erection sufficient for satisfactory sexual performance);
• erectile function (EF) domain scores of the International Index of Erectile Function (IIEF) questionnaire ≤ 25;
• age range between 19 and 40 years old;
• patients were required to be involved in a stable, monogamous relationship with a female sexual partner and having failed >50% of at least four sexual attempts during the run-in period.

Exclusion criteria were as follows:

• Men with the following conditions were excluded from the study:
• penile anatomical defects,
• spinal cord injury,
• radical prostatectomy,
• and radical pelvic surgery;
• a primary diagnosis of another sexual disorder;
• uncontrolled DM (HBA1C> 12%);
• serum creatinine>2.5mg/dL;
• major uncontrolled psychiatric disorder;
• history of major hematological, renal, or hepatic abnormalities;
• recent (within the previous 6 months) history of cardiovascular disease, stroke or myocardial infarction, cardiac failure, unstable angina, life-threatening arrhythmia and a history of alcoholism or substance abuse.
• Patients having taken PDE5 inhibitors and testosterone replacement therapy within 2 weeks were excluded in the study. Concomitant use of ED treatment was forbidden.