Fecal microbiota transplantation: a review on current formulations in <i>Clostridioides difficile</i> infection and future outlooks

The role of the gut microbiota in health and the pathogenesis of several diseases has been highlighted in recent years. Even though the precise mechanisms involving the microbiome in these ailments are still unclear, microbiota-modulating therapies have been developed. Fecal microbiota transplantation (FMT) has shown significant results against Clostridioides difficile infection (CDI), and its potential has been investigated for other diseases. Unfortunately, the technical aspects of the treatment make it difficult to implement. Pharmaceutical technology approaches to encapsulate microorganisms could play an important role in providing this treatment and render the treatment modalities easier to handle.After an overview of CDI, this narrative review aims to discuss the current formulations for FMT and specifically addresses the technical aspects of the treatment. This review also distinguishes itself by focusing on the hurdles and emphasizing the possible improvements using pharmaceutical technologies.FMT is an efficient treatment for recurrent CDI. However, its standardization is overlooked. The approach of industrial and hospital preparations of FMT are different, but both show promise in their respective methodologies. Novel FMT formulations could enable further research on dysbiotic diseases in the future.Multiple microorganisms cohabit with us: viruses, Archaea, fungi and, most predominantly, bacteria. They are called the microbiota. In fact, our body has “good” and “bad” bacteria. “Good” bacteria help us stay in good health and fight off “bad” bacteria. Recent research has revealed the relationship between the microbiota and several diseases, such as Clostridioides difficile infection.Clostridioides difficile infection (CDI) is a common hospital-acquired infection. Approximately 130 000 cases are reported every year in Europe. Severe cases appear in 6 per 100 patients and can lead to death. In addition, 13 patients among 20 will experience a recurrent infection and cannot be treated using the standard antibiotic treatment. In this disease, researchers observed an imbalance between the “good” and “bad” bacteria, among other elements. The need for procedures to regulate the microbiota has thus risen. Fecal microbiota transplantation (FMT) is a very efficient and safe treatment for recurrent CDI. One of the most significant challenges of FMT is its formulation, because it is administered via uncomfortable routes. Additionally, implementing FMT is very time consuming. As such, developing novel pharmaceutical technologies for FMT will enable the study of more diseases associated with an imbalance of the microbiota.This review explains the importance of the microbiota in CDI and how the formulation of FMT has evolved. Additionally, we propose possible ameliorations to FMT using well-established pharmaceutical technologies and how they could play a role in future research on microbiota-related diseases.