Vietnamese herbal medicine (TD0019) in the treatment of cervical radiculopathy: A double-blind phase-2 randomized controlled trial

Introduction: Cervical radiculopathy causes chronic pain and reduces patients' quality of life. Oral analgesics are commonly used but only after careful consideration due to their complications. TD0019, a Vietnamese herbal medicine, composed of Duhuo Jisheng decoction, nattokinase and an extract of Salix alba cortex has shown evidence of some benefits for these patients in pre-clinical and phase-1 studies. This study aimed to evaluate the efficacy and safety of TD0019 in the treatment of cervical radiculopathy. Methods: In this double-blind phase-2 trial, 180 patients with symptomatic cervical radiculopathy were randomized to either group 1 with intended dose of TD0019, group 2 with a higher dose (1.5 times the intended dose), or group 3, a placebo. The primary efficacy endpoint was the neck-specific disability score according to the Neck Disability Index (NDI) questionnaire. The safety endpoint included adverse events (AEs) and serious adverse events (SAEs). All patients received the drugs for 30 days and were followed for 60 days. Results: Baseline characteristics were similar for the three groups. The reduction of NDI score from baseline to the end of study was greatest for group 2 (from 17.6 +/- 7.2 to 4.8 +/- 5.1), followed by group 1 (from 16.1 +/- 6.9 to 5.4 +/- 5.1) and placebo group (from 15.6 +/- 6.2 to 7.8 +/- 6.8), with a significant decrease for both groups compared to placebo. The percentage of AEs was comparable among three groups and no SAEs occurred. Conclusions: TD0019 was superior to placebo for the reduction of symptoms with similar rates of side effects. The higher dose is more beneficial than the intended dose. This herbal medicine may be a potential alternative analgesic in the treatment of cervical radiculopathy.