2105P - Prophylactic role of a postbiotic microbiota-stabilizer on abemaciclib-induced diarrhea in breast cancer patients: A pilot application study

Background

Abemaciclib-induced diarrhea represents a major concern in clinical practice, as it can severely affect patients' quality of life and cause treatment discontinuation and dose modifications. Since growing evidence emphasize the role of microbiota in abnormal bowel clinical manifestations, a new class of natural molecules, called postbiotics, offers a potential option for managing abemaciclib-induced diarrhea.

Methods

We conducted a prospective, observational, single-arm study to evaluate the effect of the postbiotic food supplement “PostbiotiX-Restore^TM” on abemaciclib-induced diarrhea. We enrolled 36 hormone receptor-positive HER2-negative breast cancer (BC) patients at IRCCS Humanitas Research Hospital. The postbiotic was administered once daily from day -7 to the end of the first cycle of abemaciclib. From day-7 and until the end of the second cycle of abemaciclib, patients reported a daily questionnaire on bowel movements, concomitant medications, diet, and treatment discontinuation. Diarrhea was defined according to version 4.0 of the National Cancer Institute’s Common Terminology Criteria for Adverse Events. Incidence of diarrhea of any grade, its median duration and median time to diarrhea onset were assessed.

Results

An overall regularization of bowel movements in the first week of treatment with PostbioticX-Restore^TM alone was reported. Diarrhea events occurred in all patients, but predominantly G1 (87.1%) and G2 (12.3%), with a very low percentage of G3 (0.6%; all occurring during the second cycle, off postbiotic) and no G4 events. The median time to diarrhea onset was 4 days (IQR 1-41) with a median duration of G1, G2, and G3 events of 4 (IQR 1-17), 1 (IQR 1-5), and 1 (IQR 1-1) days, respectively. There was only one case of dose reduction (during the second cycle, off postbiotic) and no case of treatment withdrawal due to diarrhea.

Conclusions

Our results suggest a promising effect of PostbioticX-Restore^TM in the management of abemaciclib-induced diarrhea. Compared to pivotal trials on abemaciclib in BC patients, we observed a reduced severity and shorter duration of diarrhea.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.