Evidence Trace, complete trial record

In plain terms

In plain terms: Red Yeast Rice (Monacolin K) shows early signals in human research but the evidence is limited -- small trials, surrogate endpoints, or not yet independently replicated. It is an emerging area, not yet a proven one.

Red Yeast Rice (Monacolin K)

C Limited: small, mixed or unreplicated trials

Category Supplements

Evidence Randomized controlled trial (hard clinical endpoints)

Reviewed July 2026

PMIDs 18549841 · 19602720 · 32066811 · 30844537 · 38413255

The endpoint this grade is based on: Hard clinical endpoint (mortality, major event), Major coronary events after myocardial infarction, the primary endpoint of one large Chinese trial of one standardized extract, with cardiovascular and total mortality lower as secondary results. Monacolin K is chemically the statin lovastatin, and commercial monacolin content varies enormously.

The evidence as the record states it

Evidence record

PMID 18549841 PMID 19602720 PMID 32066811 PMID 30844537 PMID 38413255

Lu et al. (American Journal of Cardiology, 2008; PMID 18549841): the China Coronary Secondary Prevention Study (CCSPS), a randomized, placebo-controlled trial of Xuezhikang (red yeast rice extract) in nearly 5,000 post-MI patients over 4.5 years; the pre-specified primary endpoint, major coronary events (nonfatal myocardial infarction and coronary death), fell from 10.4 to 5.7 percent; cardiovascular and total mortality fell 30 and 33 percent as secondary results. Its funder is not stated in the indexed record. Li et al. (Journal of Clinical Pharmacology, 2009; PMID 19602720): CCSPS elderly hypertensive subgroup analysis. REPLICATION NOTE: Both PMIDs derive from the same CCSPS trial population. PMID 19602720 is a subgroup of PMID 18549841, not an independent replication. Rule 03 holds that a single positive trial without independent replication is a Grade C, however large or well conducted it is, and that a review of one trial and its own extension is still one trial. CCSPS is a strong trial (n=4,870, hard endpoints, significant effect) and size does not substitute for replication, so this entry is Grade C until an independent trial of the same standardized extract reports. Pooled analyses that look like replication are not: Sungthong et al. (Sci Rep, 2020; PMID 32066811) pooled 7 reports and 10,699 patients, but its hard-endpoint data come mainly from CCSPS and its own subgroup papers counted as separate studies, plus small add-on trials, so it double-counts one trial. Safety: Fogacci et al. (Pharmacol Res, 2019; PMID 30844537), 53 randomized trials, 8,535 subjects, no increase in musculoskeletal adverse events at the monacolin doses pooled; Ma et al. (J Integr Med, 2024; PMID 38413255), umbrella review of 15 meta-analyses, 12 rated critically low confidence, with signals of higher uric acid and liver enzymes.

PMID 18549841 PMID 19602720 PMID 32066811 PMID 30844537 PMID 38413255

Evidence by specific use

Secondary prevention after myocardial infarction

Grade C

Lu et al. (American Journal of Cardiology, 2008; PMID 18549841) reported the China Coronary Secondary Prevention Study: nearly 5,000 Chinese patients with a previous myocardial infarction randomized to Xuezhikang or placebo for an average of 4.5 years. The pre-specified primary endpoint, major coronary events, occurred in 10.4% on placebo against 5.7% on treatment; cardiovascular and total mortality fell by 30% and 33% as secondary results. That is a large randomized trial on hard clinical endpoints. Li et al. (Journal of Clinical Pharmacology, 2009; PMID 19602720) reports 1,530 elderly hypertensive patients from within the same study, so it is a subgroup of CCSPS rather than an independent replication: two papers, one program. On the same reasoning applied to omega-3, one unreplicated program does not reach A. The letter is C rather than B for a second reason that is specific to this record. The result belongs to Xuezhikang, one standardized extract, and monacolin K content varies markedly across commercial red yeast rice products and is often absent from the label, so the intervention cannot be reproduced from a shelf. A grade attaches to what was tested, and what was tested is not what is generally sold. Meta-analyses reporting fewer events (Sungthong et al., 2020; PMID 32066811) draw their hard-endpoint data mainly from CCSPS and its subgroup papers, so they do not replicate it.

PMID 18549841 PMID 19602720 PMID 32066811

Why Grade C and not Grade B

Grade C reflects early or limited human evidence -- small trials, surrogate endpoints, or preliminary findings not yet independently replicated. The evidence points in a promising direction but does not yet meet the standard for Grade B. A single well-powered, independently replicated trial with a meaningful endpoint would move this to Grade B or higher.

What would move this grade

A well-powered randomized trial with an objective, clinically meaningful primary endpoint and at least one independent replication would support Grade B or higher.

How to track whether this is working LDL-C was the efficacy endpoint measured in the cited trials.