An abstract presented at Digestive Disease Week 2023 claims that SIM01, a combination of probiotic and prebiotic material, alleviates symptoms of Long COVID. Gastroenteroology & Endoscopy News has a summary here:
However, there are some issues with the study…
The “Long COVID” studied seems to be lingering side effects after a mild to severe COVID infection.
In the current study, the investigators selected adults diagnosed with COVID-19 presenting with at least one symptom that had persisted for at least four weeks after their original diagnosis.
The placebo response rate was 50%, which seems too high for Long COVID. The study may be helpful but I’m not sure that it studied Long COVID.
SIM01 was previously studied in a randomized controlled trial (results) where the investigators laid out their goalposts before the study began. This helps ensure that the investigators do not move the goalposts around after-the-fact. The pre-registration can be found at NCT04884776.
For the ‘Long COVID’ study, Dr. Zarrinpar noted:
Although the study is encouraging, the findings need more clarification, Dr. Zarrinpar commented. “The precise content and mechanism of action of SIM01 remain unclear” and the study “was not registered in ClinicalTrials.gov, which is the biggest red flag for me” because it “makes it challenging to verify its objectives and power analysis,” he noted.
The headline is very clickbait-ey but on closer examination… I’m not sure what we can really learn from this study.