Author Archives: cdifffoundation

Vedanta Biosciences Phase 2 Clinical Trial Of VE303 Met Primary Endpoint Through Week 8 Compared With Placebo Of Preventing Recurrent C. difficile Infection (rCDI)

Vedanta Biosciences, a clinical-stage company that is developing a potential new category of oral therapies based on defined bacterial consortia, today announced that its Phase 2 clinical trial of VE303, an orally administered investigational live biotherapeutic product in development for the prevention of recurrent C. difficile infection (CDI) in high-risk patients, met its primary endpoint of preventing disease recurrence through Week 8.

VE303 achieved a 31.7 percent absolute risk reduction in rate of recurrence when compared with placebo, representing a greater than 80 percent reduction in the odds of a recurrence. This is the most advanced clinical trial of an investigational drug based on a rationally defined bacterial consortium, a microbiome-based therapeutic approach that delivers orally administered candidates of precisely known composition that can be manufactured with pharmaceutical-grade consistency.

The positive results of the Phase 2 study triggered a $23.8 million contract option from the Biomedical Advanced Research and Development Authority (BARDA), part of the HHS Office of the Assistant Secretary for Preparedness and Response, to support a Phase 3 clinical trial of VE303, which Vedanta plans to initiate in 2022.

“We believe these results are an important step forward for the prevention of C. difficile infection and the microbiome field at large. These data substantially add to the evidence in support of a therapeutic approach that bypasses the use of fecal donations or their spore fractions. Those first-generation approaches have shown variability in outcomes across studies, potential for transmission of infectious agents, and have significant challenges in scalability for serving large populations,” said Bernat Olle, Ph.D., Chief Executive Officer of Vedanta Biosciences. “From our inception, Vedanta has focused on delivering advances that will enable us to rationally design and manufacture – at scale – therapeutics based on defined bacterial consortia, which we believe can address the limitations of earlier approaches and potentially be broadly applicable across a range of diseases.”

Recurrent CDI causes approximately half a million infections each year in the United States, including up to 165,000 recurring infections and up to 45,000 deaths. Existing treatments include antibiotics, which can further damage the gut microbiome. This can leave patients vulnerable to both CDI recurrence and infection by a variety of other bacterial species, which could encourage the spread of antibiotic resistance. VE303 is a potential new tool against CDI that is designed to reconstitute a patient’s gut microbiome while supporting better antibiotic stewardship in the healthcare system.

Summary and topline data from the Phase 2 CONSORTIUM trial

The Phase 2 CONSORTIUM trial was a randomized, double-blind, placebo-controlled trial designed to evaluate the safety and efficacy of VE303 to treat patients at high risk of recurrent CDI.

The trial enrolled 79 patients who had completed a successful course of treatment with standard-of-care antibiotics for recurrent CDI or for a primary CDI episode with one or more characteristics that placed those patients at high risk of recurrence.

The trial evaluated low-dose VE303, high-dose VE303 (the active treatment groups), and placebo. Following completion of their standard-of-care antibiotic treatment for CDI, trial participants were randomized to one of the 3 groups and dosed once daily for two weeks. Trial participants were followed for a total of 24 weeks, to monitor for long-term safety, colonization dynamics, and additional recurrent CDI episodes.

The primary objective of the trial was to establish a dose regimen for a potential Phase 3 clinical trial, based on the safety and efficacy of the VE303 regimens compared with placebo. The primary efficacy endpoint of the trial was the CDI recurrence rate in each of the 3 groups within 8 weeks after the start of dosing. At 8 weeks, efficacy outcomes were assessed for 78 patients: 29 from the high-dose group, 27 from the low-dose group, and 22 from the placebo group.

The topline efficacy results are based on a prespecified analysis conducted after all patients had reached the Week 8 visit, using the intent-to-treat population.

The high dose of VE303 met the primary endpoint of a lower recurrence rate within 8 weeks versus placebo (13.8 percent versus 45.5 percent) using a prespecified analysis that incorporated the results of toxin and PCR testing, or a clinician’s diagnosis and treatment of a CDI recurrence when no stool sample was available for testing. This 31.7 percent reduction in absolute risk of recurrence reflects a greater than 80 percent reduction in the odds of a recurrence in the high-dose group compared with the placebo group (odds ratio 0.192; 90 percent confidence interval 0.048, 0.712; p=0.0077).

Through the Week 8 timepoint, the proportion of these high-risk patients remaining recurrence-free in the high-dose cohort was 86.2 percent, compared with 54.5 percent of the placebo recipients remaining recurrence-free at that timepoint. Using C. difficile toxin testing alone to define recurrence, which has been historically reported to miss 20 to 50 percent of CDI cases, was not a robust enough analysis to demonstrate a statistically significant difference between either of the active treatment groups and the placebo group.

“Although a number of antibiotics are approved to treat C. difficile infection, recurrence occurs frequently—often repeatedly—and is a major cause of morbidity and mortality. The CONSORTIUM trial is the first randomized, controlled trial to show that a defined bacterial consortium has the potential to prevent recurrent C. difficile infection, using an analysis that follows standard clinical practice in relying upon physician assessment, along with results of toxin and PCR testing, to establish a C. difficile diagnosis,” said Mark H. Wilcox, M.D., Professor of Medical Microbiology at the University of Leeds and a prominent CDI expert. “As defined bacterial consortia can provide consistent composition and quality and do not rely on feces obtained from human donors for manufacture or delivery, VE303 may address some of the potential issues with lack of product consistency, scalability, and risk of infection associated with existing approaches.”

Overall, VE303 was observed to be generally well-tolerated in the trial. Most participants reported one or more adverse events, but in similar proportions across groups. Few serious adverse events were reported in the trial, and none were determined to be treatment-related by either the trial investigators or Vedanta.

The final results and statistical analysis will be available following completion of long-term safety follow-up and locking of the complete trial database. Vedanta intends to present the final data analysis at a future medical conference.

Based on the Phase 2 data, BARDA has exercised its first contract option for additional funding of $23.8 million pursuant to its existing 2020 contract with Vedanta. Total committed funding under the BARDA award to date is $31.2 million, inclusive of this first contract option. The contract provides for reimbursement of up to $76.9 million, subject to additional prespecified milestones being achieved and the availability of funding.

About VE303

VE303 is an orally administered, investigational live biotherapeutic product (LBP) in development for the prevention of recurrent C. difficile infection in patients at high risk for recurrence. VE303 is produced from pure, clonal bacterial cell banks, which yield a standardized drug product in powdered form and bypasses the need to rely on direct sourcing from donor fecal material of inconsistent composition. VE303 consists of a defined consortium of eight well-characterized strains of live bacteria designed to restore colonization resistance against gut pathogens. Vedanta Biosciences received a $5.4 million research grant from the Combating Antibiotic Resistant Bacteria Biopharmaceutical Accelerator (CARB-X) in 2017 and a contract of up to $76.9 million from BARDA in 2020 to support clinical studies of VE303. VE303 was granted Orphan Drug Designation in 2017 by the U.S. FDA for the prevention of recurrent CDI.

About Vedanta Biosciences

Vedanta Biosciences is leading the development of a potential new category of oral therapies based on defined consortia of bacteria isolated from the human microbiome and grown from pure clonal cell banks. The company’s clinical-stage pipeline includes product candidates being evaluated for the treatment of high-risk C. difficile infection, inflammatory bowel diseases, advanced or metastatic cancers, and food allergy. These investigational therapies are grounded in pioneering research – published in leading journals including Science, Nature, and Cell – to identify beneficial bacteria that live symbiotically within the healthy human gut, fight pathogens and induce a range of potent immune responses. Vedanta Biosciences controls a foundational portfolio of more than 40 patents and has built what it believes to be the world’s biggest library of bacteria derived from the human microbiome. Proprietary capabilities include deep expertise in consortium design, vast datasets from human interventional studies and cGMP-compliant manufacturing of oral LBP candidates containing pure, clonally derived bacterial consortia in powdered form. Vedanta Biosciences was founded by PureTech Health (LSE: PRTC, Nasdaq: PRTC) and a global team of scientific co-founders who pioneered Vedanta’s modern understanding of the cross-talk between the microbiome and the immune system.

This project has been supported in part with federal funds from the Department of Health and Human Services; Office of the Assistant Secretary for Preparedness and Response; Biomedical Advanced Research and Development Authority, under Contract No. 75A50120C00177.

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Summit Therapeutics IDWeek 2021 E-Poster Provides Enhanced Details About the Newly Discovered Novel Mechanism of Action of Ridinilazole

Summit Therapeutics today displaying an important e-Poster at IDWeek 2021. IDWeek is the joint annual meeting of the Infectious Diseases Society of America (IDSA), Society for Healthcare Epidemiology of America (SHEA), the HIV Medical Association (HIVMA), the Pediatric Infectious Diseases Society (PIDS), and the Society of Infectious Diseases Pharmacists (SIDP).

Summit’s e-Poster provides enhanced details regarding the newly discovered novel mechanism of action of ridinilazole. The e-Poster will be available throughout IDWeek 2021, which takes place between September 29 and October 3, 2021.

Ridinilazole is Summit Therapeutics’ investigational first-in-class drug that recently completed enrollment of a Phase III clinical trial, Ri-CoDIFy. The primary endpoint of this trial seeks to demonstrate the superiority of ridinilazole in sustained clinical response as compared to vancomycin. Ridinilazole is not currently approved for use by any regulatory authority.

Summit’s poster presentation provides demonstrable scientific evidence of ridinilazole’s novel mechanism of action which involves binding to the minor groove of Clostridioides difficile bacteria’s DNA (the minor groove is a location on the helix of the bacteria’s DNA to which a drug can attach or bind). This is believed to be the primary mechanism through which ridinilazole elicits its bactericidal action against C. difficile bacteria. Ridinilazole has a novel mechanism of action and is the first of a new class of antibiotics: this is consistent with the World Health Organization’s (WHO) recommendation for developing antibiotics with novel mechanisms of action or that are new classes of drugs, which it considers a key point in overcoming existing bacterial resistance.1

Our updated research, through collaboration with the University of Houston, provides new images from high-resolution confocal microscopy. This technique has allowed intracellular visualization of ridinilazole binding to DNA within C. difficile and confirms this novel mechanism of action. Ridinilazole, if approved, has the potential to be the first antibiotic with a novel mechanism of action approved in over ten years.

The poster is available within the “Scientific Literature & Publications” section of our website:

About Summit Therapeutics

The overriding objective of Summit Therapeutics is to create value for patients, hospital caregivers, and community-based healthcare providers, as well as healthcare payers around the world. We seek to create value by developing drugs with high therapeutic efficacy – curing the cause of the patient’s condition with minimal or zero disease recurrence or antimicrobial resistance, for the longest extent possible – and minimizing the trauma caused to the patient and healthcare ecosystem by minimizing serious side effects, disease recurrence, and inaccessibility to our treatments as a result of financial or other barriers. Summit Therapeutics, empowered by its Discuva Platform, the Company’s innovative antibiotic discovery engine, and supported by BARDA and CARB-X funding, intends to be the leader in patient-friendly and paradigm-shifting treatments for infectious diseases and other significant unmet medical needs while being an ally to physicians. Our new mechanism pipeline product candidates are designed with the goal to become the patient-friendly, new-era standard of care, by working in harmony with the human microbiome to treat prospective patients suffering from infectious diseases, initially focusing on Clostridioides difficile infection (CDI). Currently, Summit’s lead product candidate, ridinilazole, is a novel, first-in-class drug engaged in a global Phase III trial program versus vancomycin, for use as first-line therapy for the treatment of initial and recurrent Clostridioides difficile infection, and to show superiority in sustained clinical response. Commercialization of ridinilazole is subject to regulatory approvals. SMT-738, the second candidate within Summit’s portfolio, is currently in the IND-enabling phase for the treatment of multidrug resistant infections, specifically those caused by carbapenem-resistant Enterobacteriaceae (CRE).

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Acurx Pharmaceuticals Presents Abstract and Poster Presentation at IDWeek: New Microbiome Data from Its Phase 2a Clinical Trial of Ibezapolstat for C. difficile Infections

Acurx Pharmaceuticals, Inc.  a clinical stage biopharmaceutical company developing a new class of antibiotics for difficult-to-treat bacterial infections, announced today that a scientific abstract and poster presentation will be given at the Infectious Disease Society of America (IDSA) IDWeekTM 2021, taking place virtually from September 29 – October 3, 2021:

Title: An Open-label Phase 2a study of Ibezapolstat, a Unique Gram-positive Selective
Spectrum (GPSS) Antibiotic, for Patients with Clostridioides difficile Infection
Presenting Author: Professor Kevin Garey, PharmD, MS, University of Houston
Date: Wednesday, September 29, 2021 through Sunday, October 3, 2021
Poster Session: Enteric Infections
Poster Number: 701

About Clostridioides difficile Infection (CDI). According to the 2017 Update (published February 2018) of the Clinical Practice Guidelines for C. difficile Infection by the Infectious Diseases Society of America (IDSA) and Society or Healthcare Epidemiology of America (SHEA), CDI remains a significant medical problem in hospitals, in long-term care facilities and in the community. C. difficile is one of the most common causes of health care- associated infections in U.S. hospitals (Lessa, et al, 2015, New England Journal of Medicine). Recent estimates suggest C. difficile approaches 500,000 infections annually in the U.S. and is associated with approximately 20,000 deaths annually. (Guh, 2020, New England Journal of Medicine). Based on internal estimates, the recurrence rate of two of the three antibiotics currently used to treat CDI is between 20% and 40% among approximately 150,000 patients treated. We believe the annual incidence of CDI in the U.S. approaches 600,000 infections and a mortality rate of approximately 9.3%.

About the Microbiome in Clostridioides difficile Infection (CDI)
C. difficile can sometimes be a normal component of the healthy gut microbiome, but when the microbiome is thrown out of balance, the C. difficile can thrive and cause an infection. After colonization with C. difficile, the organism produces and releases the main virulence factors, the two large clostridial toxins A (TcdA) and B (TcdB). (Kachrimanidou, Microorganisms 2020, 8, 200; doi:10.3390/microorganisms8020200.) TcdA and TcdB are exotoxins that bind to human intestinal epithelial cells and are responsible for inflammation, fluid and mucous secretion, as well as damage to the intestinal mucosa.

About the Ibezapolstat Phase 2 Clinical Trial.
The multicenter, open-label single-arm segment of this study (Phase 2a) is to be followed by a double- blind, randomized, active-controlled segment (Phase 2b) which, together, comprise the Phase 2 clinical trial. The Phase 2 clinical trial is designed to evaluate ibezapolstat in the treatment of CDI. Phase 2a of this trial is completed and was an open-label cohort of up to 20 subjects from study centers in the United States. In this cohort, 10 patients with diarrhea caused by C. difficile were treated with ibezapolstat 450 mg orally, twice daily for 10 days. All patients were followed for recurrence for 28± 2 days. Per protocol, after 10 patients of the projected 20 Phase 2a patients completed treatment, the Trial Oversight Committee assessed the safety and tolerability and made its recommendation regarding early termination of the Phase 2a study. Based on the recommendation of Acurx’s Scientific Advisory Board (SAB) and Trial Oversight Committee, we terminated enrollment in Phase 2a early and are now advancing to Phase 2b. The SAB unanimously supported the early termination of the Phase 2a trial after 10 patients were enrolled in the trial instead of 20 patients as originally planned. The early termination was based on the evidence of meeting the primary and secondary endpoints of eliminating the infection (100%), with no recurrences of infection (100%), and with an acceptable adverse event profile. In the upcoming Phase 2b, approximately 64 additional patients with CDI will be enrolled and randomized in a 1:1 ratio to either ibezapolstat 450 mg every 12 hours or vancomycin 125 mg orally every 6 hours, in each case, for 10 days and followed for 28 ± 2 days following the end of treatment for recurrence of CDI. The two treatments will be identical in appearance, dosing times, and number of capsules administered to maintain the blind. This Phase 2 clinical trial will also evaluate pharmacokinetics (PK) and microbiome changes and continue to test for anti-recurrence microbiome properties, including the change from baseline in alpha diversity and bacterial abundance, especially overgrowth of healthy gut microbiota Actinobacteria and Firmicute phylum species during and after therapy.

About Acurx Pharmaceuticals, Inc.
Acurx Pharmaceuticals is a clinical stage biopharmaceutical company focused on developing new antibiotics for difficult to treat infections. The Company’s approach is to develop antibiotic candidates that target the DNA polymerase IIIC enzyme and its R&D pipeline includes antibiotic product candidates that target Gram-positive bacteria, including Clostridioides difficile, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus (VRE) and drug-resistant Streptococcus pneumoniae (DRSP). To learn more about Acurx Pharmaceuticals and its product pipeline, please visit

Any statements in this press release about our future expectations, plans and prospects, including statements regarding our strategy, future operations, prospects, plans and objectives, and other statements containing the words “believes,” “anticipates,” “plans,” “expects,” and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: whether ibezapolstat will benefit from the QIDP designation; whether ibezapolstat will advance through the clinical trial process on a timely basis; whether the results of the clinical trials of ibezapolstat will warrant the submission of applications for marketing approval, and if so, whether ibezapolstat will receive approval from the United States Food and Drug Administration or equivalent foreign regulatory agencies where approval is sought; whether, if ibezapolstat obtains approval, it will be successfully distributed and marketed; and other factors. In addition, the forward-looking statements included in this press release represent our views as of September 27, 2021. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward- looking statements at some point in the future, we specifically disclaim any obligation to do so.



Seres Therapeutics Announced Data From Its Phase 3 ECOSPOR III Study Evaluating SER-109, An Investigational Oral Microbiome Therapy For Recurrent C. diff. (C. difficile) Infection

Seres Therapeutics, Inc.  a leading microbiome therapeutics company, today announced data from its Phase 3 ECOSPOR III study evaluating SER-109, an investigational oral microbiome therapy for recurrent C. difficile infection (rCDI), will be presented at the IDWeek 2021 Virtual Conference
(Sept. 29-Oct. 3). The Company will be presenting seven posters and oral presentations related to SER-109 and C. difficile, including a late-breaker, as well as an oral presentation on SER-155, an investigational cultivated microbiome therapeutic entering clinical development designed to reduce the risk of gastrointestinal antibiotic-resistant bacterial infections, bacteremia and graft-versus-host-disease (GvHD) in immunocompromised patients.

Notably, exploratory analyses of SER-109 data revealed that SER-109 was associated with improved overall and mental health scores compared to baseline regardless of clinical outcome, as measured by CDiff32 (presenting author: Kevin Garey, PharmD, M.S.). Another poster highlights that despite more than half of the patient population in ECOSPOR III having at least one co-morbidity, SER-109 was observed to significantly reduce the incidence of recurrence compared to placebo in these patients. SER-109 was observed to reduce CDI recurrence among patients at risk for recurrence because of age, gender, proton pump inhibitor use, and/or co-morbidities such as diabetes, cardiac disease and malignancy, in comparison to placebo (presenting author: Stuart Cohen, M.D.).

“The data we’re presenting at IDWeek 2021 further validates the strength of our investigational microbiome pipeline as we urgently work to address the unmet treatment needs for both recurrent C. difficile infection and immunocompromised patients,” said Lisa von Moltke, M.D., Chief Medical Officer at Seres. “We believe microbiome therapeutics have the potential to target multiple disease pathways and offer new, potentially transformative treatment options for patients in need.”

The oral presentation by Elizabeth Halvorsen, Ph.D. on SER-155, an investigational cultivated microbiome therapeutic, will highlight preclinical data showing that SER-155 can decolonize antibiotic-resistant pathogens (VRE: vancomycin-resistant Enterococcus faecium and CRE: carbapenem-resistant Klebsiella pneumoniae); potentially reducing the risk of subsequent infection.

In addition, Seres is presenting the following SER-109-related posters and a late-breaker presentation at IDWeek 2021:

SER-109, an Investigational Microbiome Therapeutic, Reduces Abundance of Antimicrobial Resistance Genes in Patients with Recurrent Clostridioides difficile Infection (rCDI) after Standard-of-Care Antibiotics, Saturday, October 2, 1:15 PM – 3:00 PM ET, Presenting Author: Timothy Straub (late-breaker)

Manufacturing Processes of SER-109, a Purified Investigational Microbiome Therapeutic, Reduce Risk of Transmission of Emerging and Undetected Infections in Donor Stool, Presenting Author: Christopher McChalicher

Diagnostic Testing Among Patients with Suspected Recurrent Clostridioides difficile Infection (rCDI) in ECOSPOR III a Phase 3 Clinical Trial: Implications for Clinical Practices vs Clinical Trials, Presenting Author: Matthew Sims

Time to Recurrence of Clostridioides difficile Infection (rCDI) is Rapid Following Completion of Standard of Care Antibiotics: Results from ECOSPOR-III, a Phase 3 Double-Blind, Placebo-Controlled Randomized Trial of SER-109, an Investigational Microbiome Therapeutic, Presenting Author: Thomas Louie

The Burden of Illness Associated with Recurrent Clostridioides difficile Infection: A Claims-based Analysis, Presenting Author: Rachel Black

In addition, Paul Feuerstadt, M.D. will be providing a sponsored talk on Friday, October 1 at 2:00-2:45 PM ET, entitled “Perspectives on the Pathogenesis of Recurrent Clostridioides difficile Infection: Insights into Microbiome Science.”

The data is available to registered attendees on the virtual platform throughout the duration of the IDWeek Conference at

About SER-109

SER-109 is an oral microbiome therapeutic candidate consisting of a consortium of highly purified Firmicutes spores, which normally live in the healthy microbiome. SER-109 is designed to prevent further recurrences of CDI in patients with a history of multiple infections by modulating the disrupted microbiome to a state that resists C. difficile colonization and growth. The SER-109 manufacturing purification process is designed to remove unwanted microbes thereby reducing the risk of pathogen transmission beyond donor screening alone. The U.S. FDA has granted SER-109 Breakthrough Therapy designation and Orphan Drug designation for the treatment of rCDI.

About SER-155

SER-155, an oral consortium of cultivated bacteria, is a microbiome therapeutic candidate intended to advance into clinical development. SER-155 is designed using microbiome biomarker data from human clinical data, human cell-based assays, and in vivo disease models, with the aim to decrease infection and translocation of antibiotic-resistant bacteria in the gastrointestinal tract and modulate host immune responses to decrease GvHD. The rationale for this program is based in part on published clinical evidence from Seres’ collaborators at Memorial Sloan Kettering Cancer Center showing that allogeneic hematopoietic stem-cell transplantation (HSCT) patients with decreased diversity of commensal microbes are significantly more likely to die due to infection and/or GvHD. SER-155 was developed using Seres’ reverse translational discovery platform to reduce morbidity and mortality due to gastrointestinal infections, bacteremia and GvHD in immunocompromised patients, including in patients receiving allogeneic HSCT or solid organ transplants.

About Seres Therapeutics

Seres Therapeutics, Inc. (Nasdaq: MCRB) is a leading microbiome therapeutics company developing a novel class of multifunctional bacterial consortia that are designed to functionally interact with host cells and tissues to treat disease. Seres’ SER-109 program achieved the first-ever positive pivotal clinical results for a targeted microbiome drug candidate and has obtained Breakthrough Therapy and Orphan Drug designations from the FDA. The SER-109 program is being advanced for the treatment of recurrent C. difficile infection and has potential to become a first-in-class FDA-approved microbiome therapeutic. Seres is evaluating SER-301 in a Phase 1b study in patients with ulcerative colitis and SER-155 in a Phase 1b study to address gastrointestinal infections, bacteremia and graft-versus-host disease. For more information, please visit

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including the potential approval of SER-109 and its status as a first-in-class therapeutic, the timing of a BLA filing, the ultimate safety profile of SER-109, the ultimate market for SER-109, the potential for microbiome therapeutics to improve the outcome of immunocompromised patients, the ability of SER-109 to improve rCDI patients’ quality of life, the potential of microbiome therapeutics to treat and prevent disease, the timing and results of our clinical studies, the benefits of our collaborations, the ultimate safety and efficacy data for our products, and other statements which are not historical fact.

These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: we have incurred significant losses, are not currently profitable and may never become profitable; our need for additional funding; our limited operating history; the impact of the COVID-19 pandemic; our unproven approach to therapeutic intervention; the lengthy, expensive and uncertain process of clinical drug development; our reliance on third parties and collaborators to conduct our clinical trials, manufacture our product candidates and develop and commercialize our product candidates, if approved; and our ability to retain key personnel and to manage our growth. These and other important factors discussed under the caption “Risk Factors” in our Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission, or SEC, on August 3, 2021, and our other reports filed with the SEC could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.



Gut Microbiome and Dietary Fiber Diet Influences Microbial Metabolism

In normal conditions, meal ingestion induces satiation and fullness which, depending on the type of foods ingested, individual sensitivity and reflex activity, may have a pleasurable dimension leading to digestive well-being. However, 84% of people with IBS experience digestive symptoms related to food intake, including abdominal pain, bloating and abdominal distension, which are not secondary to structural abnormalities in their digestive tract.

The study of factors that determine digestive sensations is currently an active area of research for scientists such as those at the University Hospital Vall d’Hebron in Barcelona, Spain.

A new cross-over, randomized study, led by Dr. Fernando Azpiroz from the Digestive System Research Unit at University Hospital Vall d’Hebron, elucidates how diet influences gut microbiota composition and metabolic activity, colon biomass and perception of digestive sensations in healthy individuals.

The authors administered a high-fat and low-residue diet (Western-type diet; 4.7 g fiber from food sources) versus a low-fat and high-residue diet (fiber-enriched Mediterranean diet; 54.2 g fiber from food sources) for two weeks in 20 healthy men after a period of two weeks on a balanced diet. Thus, all participants received both interventions, but the order in which they were received was randomized.

Although the two diet types were well tolerated, leading to a sensation of digestive well-being, the fiber-enriched Mediterranean diet led to high scores of flatulence and rumbling sounds caused by gas moving through the intestines and a higher number of anal gas evacuations. Stool consistency, stool weight and colonic content were also higher in participants on the fiber-enriched Mediterranean diet.

Although at the gut microbiota composition level some genus and species were enriched in participants who followed the fiber-enriched Mediterranean diet, a core gut microbiota was shared regardless of dietary intervention.

In contrast, both diets had a notable effect on gut microbiota metabolic activity. As such, a total of 27 metabolic pathways showed higher expression following the fiber-enriched Mediterranean diet. It is interesting to note that not all the genomes found in gut microbial communities were influenced in the same way by diet. For example, the fiber-enriched Mediterranean diet led to a gut microbiome with high diversity and enriched in up to 1322 gene families with a less anal gas evacuation in participants with a gut microbiota that did not change after each intervention (i.e., robust gut microbiota).

The results suggest that the metabolic capacity of the gut microbiome might adapt to dietary substrates so dietary fiber does not necessarily be the culprit of symptoms in all people. While patients with gut-brain interaction disorders such as irritable bowel syndrome usually exclude fiber from their diet as means to improve symptoms, the current findings show this choice could not relate to anal gas evacuations in a subset of people.

A short period of two weeks was enough time for the gut microbiota to adapt to dietary substrates, which highlights the importance of evaluating in a personalized way the need to exclude dietary fiber for managing digestive issues. Indeed, a small amount (10 g) of fiber daily has been shown to be enough to selectively promote the growth of beneficial Bifidobacterium species in the gut. Furthermore, a previous intervention study showed that low-dose prebiotics were superior to the known exclusion FODMAP diet for managing digestive symptoms, suggesting that digestive symptoms can be alleviated by modulating the metabolic activity and composition of the intestinal microbiota with diet.

In conclusion, the findings show that although diet does not always lead to changes in gut microbiota composition, it can have a profound effect on gut microbial metabolic functions. That, in turn, can have implications for healthy subjects and patients with digestive symptoms with no detectable abnormalities according to conventional diagnostic methods.


Böhn L, Störsrud S, Törnblom H, et al. Self-reported food-related gastrointestinal symptoms in IBS are common and associated with more severe symptoms and reduced quality of life. Am J Gastroenterol. 2013; 108(5):634-641. doi: 10.1038/ajg.2013.105.

Barber C, Mego M, Sabater C, et al. Differential effects of Western and Mediterranean-type diets on gut microbiota: A metagenomics and metabolomics approach. Nutrients. 2021; 13(8):2638. doi: 10.3390/nu13082638.

So D, Whelan K, Rossi M, et al. Dietary fiber intervention on gut microbiota composition in healthy adults: A systematic review and meta-analysis. Am J Clin Nutr. 2018; 107(6):965-983. doi: 10.1093/ajcn/nqy041.

September 27th, 2021
By Andreu Prados:  Andreu Prados holds a Bachelor of Science Degree in Pharmacy & Human Nutrition and Dietetics. Science writer special in gut microbiota and probiotics, working also as lecturer and consultant in nutrition and healthcare