A traditional Chinese medicine compound used for cardiac benefits might help reduce the incidence of major adverse cardiac and cerebrovascular events and even cardiac death rates, according to a new study published in the Journal of the American Medical Association.

Tongxinluo, a traditional Chinese medicine compound, has shown promise in in vitro, animal, and small human studies for myocardial infarction, but has not been rigorously evaluated in large randomized clinical trials. So a group of researchers set out to investigate whether Tongxinluo could improve clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI).

Tongxinluo in Chinese means “to open (tong) the network (luo) of the heart (xin),” The compound, consists of a mixture of powders and extracts derived from plants, centipedes, cicada, and other sources. It has been approved in China for the treatment of angina and stroke since 1996. The product may be purchased online as a dietary supplement.

A randomized, double-blind, placebo-controlled clinical trial was conducted among patients with STEMI within 24 hours of symptom onset from 124 hospitals in China. Patients were enrolled from May 2019 to December 2020; the last date of follow-up was December 15, 2021.

Patients were randomized 1:1 to receive either Tongxinluo or placebo orally for 12 months (a loading dose of 2.08 g after randomization, followed by the maintenance dose of 1.04 g, 3 times a day), in addition to STEMI guideline-directed treatments. Among 3797 patients who were randomized, 3777 (Tongxinluo: 1889 and placebo: 1888; mean age, 61 years; 76.9% male) were included in the primary analysis.

In patients with STEMI, the Chinese patent medicine Tongxinluo, as an adjunctive therapy in addition to STEMI guideline-directed treatments, significantly improved both 30-day and 1-year clinical outcomes. But the authors caution that further research is needed to determine the mechanism of action of Tongxinluo in STEMI.

This current study is consistent with smaller studies that essentially came to the same conclusion. In a 2006 published study, authors systematically reviewed evidence from 18 randomised controlled trials for the benefit of tongxinluo with or without other treatments, including routine care or placebo, for patients with unstable angina.

All the trials were conducted in China. The total number of participants was 1413, ranging in age from 25 to 88 years. Most studies randomized patients to receive tongxinluo with conventional medication or conventional medications alone.

The evidence suggested possible benefits relating to a range of outcomes among patients with unstable angina but all the studies were of poor quality and neither blinding nor allocation concealment were used. This makes it impossible to reach firm conclusions about the benefit of this treatment. Thus, in 2006 the authors concluded “Large, high quality, randomized controlled trials are needed to confirm the possible benefit of tongxinluo for unstable angina and to suggest appropriate future use of this herbal medicine.

The editorialist, Richard Bach evaluated the work with a note of skepticism. In his Editorial, Bach raises questions that “underscore lingering uncertainties about the trial results and the use of Tongxinluo outside of China.” But he also notes that the malaria drug artemisinin was isolated from a traditional Chinese medicine, and this research was later awarded the Nobel Prize in Physiology or Medicine.

The 2015 Nobel Prize in Physiology or Medicine was awarded to Professor Youyou Tu for her key contributions to the discovery of artemisinin. Artemisinin has saved millions of lives and represents one of the significant contributions of China to global health. Many scientists were involved in the previously unknown 523 Project, and the Nobel Prize given to a single person has not been without controversy.