According to the findings of a prospective study, the gut microbiota, particularly the Blautia genus, appears to be a crucial predictor of symptom relief in irritable bowel syndrome with constipation (IBS-C) patients treated with Linaclotide. This multicenter, pre-post clinical trial by Jianyun Zhou and other researchers aimed to decipher how Linaclotide affects the gut microbiota and identify key bacterial genera that could influence its effectiveness.

A total of 62 IBS-C-affected patients were enrolled. Participants received a daily dose of 290 µg of Linaclotide for six weeks, with their symptoms monitored for an additional four weeks post-treatment. Collection of fecal samples was done prior to and after treatment. This was followed by 16S rRNA sequencing. This was executed in order to analyze the changes in the gut microbiota's composition. For estimating short-chain fatty acids (SCFAs) concentrations, targeted metabolomics were utilized.

Following six weeks of Linaclotide use, 43.3% of participants fulfilled the Food and Drug Administration (FDA) responder endpoint, and 85% reported relief from constipation and abdominal pain. Linaclotide markedly altered the SCFA metabolism and gut microbiome. Higher Linaclotide effectiveness correlated with increased abundance of the Blautia genus. Post-treatment, Blautia levels exceeded those of healthy volunteers.

Moreover, a positive correlation emerged between Blautia abundance, SCFA concentrations, and symptom betterment in IBS-C sufferers. Hence, combining Linaclotide treatment with Blautia supplementation could enhance the effectiveness of clinical therapy for IBS-C.