Semaglutide linked to 37.8% drop in inflammation marker in SELECT analysis

A prespecified secondary analysis of the SELECT trial reports that semaglutide lowered high-sensitivity C-reactive protein (hsCRP), a blood marker of inflammation, by 37.8% at 104 weeks ^[1]. The analysis was published in Circulation ^[1].

hsCRP is measured with a blood test and reflects low-level inflammation in the body. In the analysis, the 37.8% reduction was recorded at 104 weeks, about two years after treatment began ^[1]. Reductions were already visible by weeks 4 and 8, meaning the marker moved early rather than only after long-term treatment ^[1].

The analysis also found hsCRP reductions among participants who lost little weight ^[1]. That finding is the reason the question of whether semaglutide lowers inflammation by a route separate from weight loss has drawn attention. The authors did not go that far: they stopped short of claiming a weight-independent mechanism ^[1]. So what drove the drop, whether weight loss, a direct effect of the drug, or a mix of the two, is not settled by this analysis.

Semaglutide is the active ingredient in Ozempic, Wegovy and Rybelsus. The analysis concerns semaglutide only, not tirzepatide (sold as Mounjaro and Zepbound) or orforglipron (Foundayo) ^[1].

A 37.8% figure is a relative change in a laboratory value, not a count of health events. Absolute hsCRP levels, the share of participants who fell below any particular threshold, and whether the reduction held after 104 weeks have not been reported ^[1].

Why it matters for patients

hsCRP is a lab number, not a symptom. People generally cannot feel whether their hsCRP is high or low, so a 37.8% drop is not something a patient would notice the way they might notice weight loss or a change in blood pressure.

The practical question for anyone taking or considering semaglutide is whether a lower inflammation marker means fewer heart attacks, strokes, hospitalizations or deaths. This analysis reports the marker change; it does not report whether that change translated into fewer cardiovascular events ^[1]. A marker that improves is not the same as an outcome that improves, and the report does not close that gap.

The finding that hsCRP fell even among participants who lost little weight may be relevant to people who do not lose much weight on semaglutide. Even so, the analysis does not show a clinical benefit for that group; it shows a change in a blood test ^[1].

Nothing in the analysis describes how or whether hsCRP is monitored for people taking semaglutide, and it does not say which patients, if any, would benefit from having the test ^[1].

Another limit: the analysis covers semaglutide. Whether tirzepatide or orforglipron produce similar changes in hsCRP is not addressed ^[1].

What is not yet known

• Whether semaglutide lowers inflammation independently of weight loss. The authors declined to claim that ^[1].
• The absolute hsCRP values behind the 37.8% relative change, and whether the reduction persisted beyond 104 weeks ^[1].
• Whether the marker change is tied to any difference in cardiovascular events for patients ^[1].
• Whether the same pattern appears with other GLP-1 or related medicines ^[1].

SELECT is a semaglutide trial, and this report is one prespecified secondary analysis of it ^[1]. Secondary analyses examine questions the trial was not primarily built to answer, which is one reason the authors framed the inflammation result carefully. The 104-week timeframe also means the report describes what happened during treatment, not what happens after it stops, which has not been reported ^[1].

For now, the analysis adds a specific number, 37.8% at 104 weeks, to a discussion that has mostly rested on smaller and shorter studies of inflammation markers with this class of drugs ^[1]. It does not change what is known about how semaglutide affects cardiovascular outcomes, because that question is outside what this analysis reports ^[1].