RESUMO
Objective: To investigate the analgesic efficacy and safety of state-dependent sodium channel blocker-bulleyaconitine combined with calcium channel blocker-gabapentin on postherpetic neuralgia (PHN). Methods: A double-blind, randomized, placebo-controlled, parallel-group, multi-center study involving Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Qinghai Provincial People's Hospital, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine Affiliated to Shanghai University of Traditional Chinese Medicine, the Second Affiliated Hospital of Kunming Medical University was performed from September 2018 to December 2019. A total of 75 PHN patients were randomly divided into the experiment group (n=41) and the control group (n=34). On the basis of first-line treatment with gabapentin, the experiment group was given bulleyaconitine A tablets, while the control group was given placebo. The primary outcome was a 50% improvement in the visual analogue scale (VAS), and the effective rate of achieving the primary outcome between the two groups was compared; the Cox regression model was used to analyze the impact of related factors on the disease outcome. Secondary outcomes including scores of pain scales (ID-pain, DN4), Patient Health Questionnaire (PHQ-9), 7-item Generalized Anxiety Disorder (GAD-7) at 1, 2, 3, 4, 8, 12 weeks after treatment were applied to evaluate the efficacy and safety of the combination of bulleyaconitine A tablets with first-line drug in the treatment of PHN. Results: The effective rate was 68.3% (28/41) and the time reached the primary outcome was 28 (7, 84) days in the experiment group, while in the control group, the effective rate was 52.9% (18/34) and the time reached the primary outcome was 56 (14, 84) days. Cox regression analysis indicated that the grouping factor of oral bulleyaconitine A tablets was an independent factor for improving the outcome of PHN (HR=2.063, 95%CI: 1.059-4.018, P<0.05), and the probability of the experiment group reaching the primary outcome was 2.063 times that of the control group (P<0.05). Meanwhile, the outcome probability of the long disease course group (>6 months) was only 0.201 times that of the short disease course group (<6 months) (HR=0.201, 95%CI: 0.073-0.551, P<0.05). There was no statistically significant difference in the trend of VAS between the two groups (P>0.05). The scores of ID-pain, DN4, PHQ-9, and GAD-7 of the two groups were significantly improved compared with those before enrollment (P<0.05), but the differences between the two groups were not statistically significant (all P>0.05). Conclusion: Bulleyaconitine A tablet can promote the therapeutic efficacy of gabapentin, and improve the outcome of PHN in a short period of 3 months.