Category Archives: Clinical Trials

SYN-004 (ribaxamase) For C. difficile Prevention Advances; U.S. Food and Drug Administration (FDA) Has Granted A Breakthrough Therapy Designation

On May 11, 2017 Synthetic Biologics, Inc. a late-stage clinical company developing therapeutics that preserve the microbiome to protect and restore the health of patients, announced that the U.S. Food and Drug Administration (FDA) has granted a Breakthrough Therapy Designation for SYN-004 (ribaxamase) for the prevention of Clostridium difficile infection.

SYN-004 (ribaxamase) is the Company’s first-in-class oral enzyme designed to protect the gut microbiome from disruption caused by certain intravenous (IV) beta-lactam antibiotics.

The Breakthrough Therapy Designation is based on data from the successful Phase 2b clinical trial of ribaxamase, which met its primary endpoint of significantly reducing CDI. FDA Breakthrough Therapy Designation is intended to expedite development and review timelines when preliminary clinical evidence indicates that a drug may demonstrate substantial improvement on one or more clinically significant endpoints over available therapies for serious or life threatening diseases. If approved by the FDA, SYN-004 (ribaxamase) would be the first available drug designed to prevent Clostridium difficile infection by protecting the gut microbiome from antibiotic-mediated dysbiosis.

“We are delighted by the FDA’s recognition of ribaxamase’s potential to prevent CDI, and the dire need to fill the current void of an approved intervention,” said Jeffrey Riley, President and Chief Executive Officer. “Following this announcement, we have been asked and anticipate requesting a Type-B multidisciplinary meeting with the Agency for a comprehensive discussion on the overarching, high-level drug development plan and pathway to licensure for ribaxamase. We look forward to working closely with the FDA throughout the development and review process and remain dedicated to bringing this potentially paradigm-shifting approach to antibiotic therapy to patients in critical need.”

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C. diff. Spores and More Global Broadcasting Network 

www.cdiffradio.com

Protecting the Gut Microbiome: A Paradigm Shift in Managing GI Disorders

Live Broadcast On Tuesday, May 16th Join us with our guest, Dr. Joseph Sliman, MD, MPH, Chief Medical Officer of Synthetic Biologics.  Dr. Sliman will be discussing  the protection of the natural gut microbiome from the unintended consequences of intravenous (IV) antibiotics which are excreted into the gut is expected to protect against opportunistic enteric infections. Synthetic Biologics is developing two microbiome-focused drug candidates in Phase 3 development including, SYN-004 (ribaxamase) which is designed to protect the gut microbiome by degrading certain IV beta-lactam antibiotics for the prevention of Clostridium difficile infection (CDI), pathogenic
overgrowth and the emergence of antimicrobial resistance, and SYN-010 which is intended to reduce the impact of methane producing organisms in the gut microbiome to treat an underlying cause of irritable bowel syndrome with constipation (IBS-C).

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To learn more about Synthetic Biologics, please click on the link provided below

.http://www.syntheticbiologics.com/about/overview

Source:  Synthetic Biologics

Synthetic Biologics – Protecting the Gut Microbiome: A Paradigm Shift in Managing GI Disorders

Ridinilazole Compared With Vancomycin For Efficacy and Safety For Treatment of C. difficile Infection; A Phase 2 Randomized,Double-Blind,Active-Controlled,Non-Inferiority Study

Article Summary:

Background

Clostridium difficile infection is the most common health-care-associated infection in the USA. We assessed the safety and efficacy of ridinilazole versus vancomycin for treatment of C difficile infection.

Methods

We did a phase 2, randomized, double-blind, active-controlled, non-inferiority study. Participants with signs and symptoms of C difficile infection and a positive diagnostic test result were recruited from 33 centres in the USA and Canada and randomly assigned (1:1) to receive oral ridinilazole (200 mg every 12 h) or oral vancomycin (125 mg every 6 h) for 10 days. The primary endpoint was achievement of a sustained clinical response, defined as clinical cure at the end of treatment and no recurrence within 30 days, which was used to establish non-inferiority (15% margin) of ridinilazole versus vancomycin. The primary efficacy analysis was done on a modified intention-to-treat population comprising all individuals with C difficile infection confirmed by the presence of free toxin in stool who were randomly assigned to receive one or more doses of the study drug. The study is registered with ClinicalTrials.gov, number NCT02092935.

Findings

Between June 26, 2014, and August 31, 2015, 100 patients were recruited; 50 were randomly assigned to receive ridinilazole and 50 to vancomycin. 16 patients did not complete the study, and 11 discontinued treatment early. The primary efficacy analysis included 69 patients (n=36 in the ridinilazole group; n=33 in the vancomycin group). 24 of 36 (66·7%) patients in the ridinilazole group versus 14 of 33 (42·4%) of those in the vancomycin group had a sustained clinical response (treatment difference 21·1%, 90% CI 3·1–39·1, p=0·0004), establishing the non-inferiority of ridinilazole and also showing statistical superiority at the 10% level. Ridinilazole was well tolerated, with an adverse event profile similar to that of vancomycin: 82% (41 of 50) of participants reported adverse events in the ridinilazole group and 80% (40 of 50) in the vancomycin group. There were no adverse events related to ridinilazole that led to discontinuation.

Interpretation

Ridinilazole is a targeted-spectrum antimicrobial that shows potential in treatment of initial C difficile infection and in providing sustained benefit through reduction in disease recurrence. Further clinical development is warranted.

Funding

Wellcome Trust and Summit Therapeutics.

To read the article in its entirety, please click on the following link:

http://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30235-9/fulltext

Dr Richard J Vickers, PhD'Correspondence information about the author Dr Richard J Vickers
Glenn S Tillotson, PhD

,

Richard Nathan, MD

,

Sabine Hazan, MD

,

John Pullman, MD

,

Christopher Lucasti, DO

,

Kenneth Deck, MD

,

Prof Bruce Yacyshyn, MD

,

Benedict Maliakkal, MD

,

Yves Pesant, MD

,

Bina Tejura, MD

,

Prof David Roblin, FRCP

,

Prof Dale N Gerding, MD

,

Prof Mark H Wilcox, MD

for the

See appendix for full details of the CoDIFy study group
Published: 28 April 2017
Open Access Article has an altmetric score of 76

Open access funded by Wellcome Trust

Rebiotix Reports Topline Results From a Controlled Open-label Phase 2 Trial of RBX2660 (PUNCH™ Open Label) For the Prevention of Recurrent Clostridium difficile (C. diff.) Infection (rCDI)

In The News

April 2017

 

 

Rebiotix Inc., a clinical-stage microbiome company focused on harnessing the power of the human microbiome to treat challenging diseases, today announced topline results from a controlled open-label Phase 2 trial of RBX2660 (PUNCH™ Open Label) for the prevention of recurrent Clostridium difficile (C. diff.) infection.

Data indicated that RBX2660 was well-tolerated and achieved the primary efficacy endpoint of preventing C. diff. recurrence; patients treated with RBX2660 exhibited a treatment success rate of 78.8% compared with a historical control of 51.8% (p<0.0001). RBX2660 is a broad-spectrum microbiota suspension that is designed to rehabilitate the human microbiome by delivering live microbes into a patient’s intestinal tract to treat disease.

Lee Jones, president and CEO of Rebiotix, stated, “The 78.8% treatment success achieved in this open label Phase 2 trial demonstrates the potential of RBX2660, a broad spectrum microbiota drug product, to rehabilitate the gut microbiome and break the cycle of C. diff. recurrence. These results, coupled with the safety and efficacy data observed in our prior Phase 2b and Phase 2 clinical trials, position Rebiotix to advance RBX2660 into Phase 3 clinical development, solidifying our standing as the most clinically advanced microbiome company in the industry.”

PUNCH™ Open Label was designed as a prospective, multicenter, open-label, controlled Phase 2 study to assess the efficacy and safety of RBX2660 for the prevention of recurrent C. diff.

The primary efficacy endpoint involved a comparison of patients treated with RBX2660 to a closely matched set of antibiotic only treated historical controls through 56 days. There were 31 active treatment sites and four control sites in the US and Canada. 132 RBX2660 and 110 historical control subjects were included in this topline analysis.

Actively treated patients, after determining eligibility, were administered two doses of RBX2660; the first at day one and the second at day seven. Patients were then monitored for eight weeks to determine whether there was a recurrence of C. diff.

Top line results from the trial, which examined responses from 132 patients versus a historical control of 110 patients, indicated a treatment success rate of 78.8% as compared to a historical control of 51.8% (p<0.0001). Overall, RBX2660 was generally well-tolerated with the most commonly reported adverse events being gastrointestinal, including diarrhea, abdominal pain, flatulence, constipation and distension.


About Rebiotix Inc.

Rebiotix Inc. is a clinical-stage microbiome company focused on harnessing the power of the human microbiome to revolutionize the treatment of challenging diseases. Rebiotix is the most clinically advanced microbiome company in the industry, with its lead drug candidate, RBX2660, expected to enter Phase 3 clinical development for the prevention of recurrent Clostridium difficile (C. diff.) infection. Previously, RBX2660 was the subject of three Phase 2 trials in recurrent C. diff, including a Phase 2b randomized, double-blind, placebo-controlled trial (PUNCH™ CD2), with data indicating the drug was well-tolerated and demonstrated statistically significant treatment efficacy. RBX2660 has been granted Orphan Drug status, Fast Track status and Breakthrough Therapy Designation from the FDA for its potential to prevent recurrent C. diff. infection.

Rebiotix’s development pipeline includes multiple formulations targeting several disease indications and is built around its pioneering Microbiota Restoration Therapy (MRT) platform. MRT is a standardized, stabilized drug technology that is designed to rehabilitate the human microbiome by delivering a broad spectrum of live microbes into a patient’s intestinal tract via a ready-to-use and easy-to-administer format.

For More Information About C. difficile Clinical Trials In Progress : 

https://cdifffoundation.org/clinical-trials-2/

 

For more information on Rebiotix and its pipeline of human microbiome-directed therapies, visit www.rebiotix.com

 

Source:  Rebiotix 4/17

Clostridium difficile Vaccines In Trials Reviewed by Larry K. Kociolek, MD and Stanford T. Shulman, MD

CDI is not only observed in hospitalized patients and patients with antibiotic exposure but also in populations previously thought to be at low risk, such as healthy young adults and children. Community-associated CDI has also emerged as an important cause of diarrheal illness.4,5 The spectrum of CDI ranges from asymptomatic carriage and mild diarrhea to life-threatening pseudomembranous colitis, toxic megacolon, and fulminant colitis potentially requiring urgent colectomy.4-6 Furthermore, long-term resolution of symptoms is difficult to achieve in a large percentage of patients with CDI; approximately 20% of patients with CDI experience recurrent infection after responding to initial therapy.2

To read the article in its entirety please click the link below:

http://www.infectiousdiseaseadvisor.com/clostridium-difficile/status-of-clostridium-difficile-vaccines/article/646015/

Although the pathophysiology of CDI is complex and multifactorial, toxin B (TcdB), a cytotoxin, is now thought to be the primary mediator of symptomatic infection. Toxin A (TcdA) and binary toxin (in particular strains such as epidemic strain BI/NAP1/027) are also likely to do so, but the extent to which they contribute to disease is unclear.5 A mature and varied intestinal microbiome confers resistance to colonization by C difficile, protecting against CDI.6 Thus, exposure to C difficile spores alone is rarely sufficient to cause CDI, while perturbation of the microbiome following antibiotic exposure permits C difficile spores to colonize, germinate, and release toxins that induce CDI symptoms.

Antibodies to TcdA and TcdB mediate protection against primary CDI and recurrences. High serum antitoxin levels, especially immunoglobulin G (IgG) antitoxin A, are associated with asymptomatic colonization and protection against CDI recurrence.7

Bezlotoxumab, a monoclonal antibody against TcdB recently approved by the US Food and Drug Administration (FDA), reduces the rate of CDI recurrence in adults.8 However, the protective effect of this passive immunization strategy is short-lived.

Vaccines appear to be a promising intervention that provides long-term protection against CDI episodes, and several are in various stages of development.6 There are 3 candidate vaccines currently undergoing phase 2 and 3 clinical evaluation for CDI prevention.6

The Sanofi Pasteur toxoid vaccine uses formalin-inactivated full-length TcdA and TcdB administered by intramuscular injection at days 0, 7, and 30. In phase 2 trials, the vaccine was safely administered to adults older than 50, and seroconversion to TcdA and TcdB was 97% and 92%, respectively.9 The high-dose adjuvanted vaccine, which is currently being evaluated in a phase 3 clinical trial, has demonstrated elevated circulating titers for up to 3 years after the last dose of the primary series given at 0, 7, and 30 days.10

Pfizer is currently evaluating a genetically modified and chemically treated recombinant full-length TcdA and TcdB vaccine in a phase 2 trial. In a phase 1 trial with 3 different dosages given as a 3-dose schedule in adults 50 to 85 years old, satisfactory immunogenicity and safety were demonstrated for both the aluminum hydroxide-adjuvanted and non-adjuvanted vaccine.11 Best responses were observed with the non-adjuvanted formulation, and there were no differences in responses in 50- to 64 year-old and 65- to 80 year-old subjects.

Valneva, an Austrian pharmaceutical company, is developing VLA84, a genetic fusion of the truncated cell-binding domains of TcdA and TcdB that is purported to be less complex to produce and purify compared with the toxoid vaccines. In a phase 1 trial, VLA84 was shown to be highly immunogenic in adults and the elderly without serious adverse effects.12 A phase 2 clinical trial has been completed, but data are not yet available.

All 3 of these parenteral candidate vaccines are moving forward in development and appear promising for the prevention of symptomatic CDI. An oral mucosal vaccine using a genetically engineered Bacillus subtilis vector is also in development.13 Because host immune response against non-toxin antigens may additionally protect against colonization and subsequent transmission, an alternative possibility of developing vaccines against surface proteins that prevent C difficile mucosal adherence and colonization is attractive. To this end, a number of surface-associated antigens including flagellar proteins, S-layer proteins, proteases, and complex polysaccharides have been studied in animal models as possible vaccine candidates.14

Larry K. Kociolek, MD, is the associate medical director of Infection Prevention and Control at The Ann & Robert H. Lurie Children’s Hospital of Chicago and assistant professor of Pediatrics at the Northwestern University Feinberg School of Medicine in Illinois.

Stanford T. Shulman, MD, is the medical director of Infection Prevention and Control at The Ann & Robert H. Lurie Children’s Hospital of Chicago and Virginia H. Rogers Professor of Pediatric Infectious Disease​ at the Northwestern University Feinberg School of Medicine​ in Illinois.

References

  1. Magill SS, Edwards JR, Bamberg W, et al; Emerging Infections Program Healthcare-Associated Infections and Antimicrobial Use Prevalence Survey Team. Multistate point-prevalence survey of health care-associated infections. N Engl J Med. 2014;370:1198-1208. doi:10.1056/NEJMoa1306801
  2. Lessa FC, Mu Y, Bamberg WM, et al. Burden of Clostridium difficile infection in the United States. N Engl J Med. 2015;372:825-834. doi:10.1056/NEJMoa1408913
  3. Dubberke ER, Olsen MA. Burden of Clostridium difficile on the healthcare system. Clin Infect Dis. 2012;55 Suppl 2:S88-S92. doi:10.1093/cid/cis335
  4. Chitnis AS, Holzbauer SM, Belflower RM, et al. Epidemiology of community-associated Clostridium difficile infection, 2009 through 2011. JAMA Intern Med. 2013;173:1359-1367. doi:10.1001/jamainternmed.2013.7056
  5. Kelly CP, Lamont JT. Clostridium difficile–more difficult than ever. N Engl J Med. 2008;359:1932-1940. doi:10.1056/NEJMra0707500
  6. Kociolek LK, Gerding DN. Breakthroughs in the treatment and prevention of Clostridium difficile infections. Nat Rev Gastroenterol Hepatol. 2016;13:150-160. doi:10.1038/nrgastro.2015.220
  7. Kelly CP, Kyne L. The host immune response to Clostridium difficile. J Med Microbiol. 2011;60:1070-1079. doi:10.1099/jmm.0.030015-0
  8. Wilcox MH, Gerding DN, Poxton IR, et al; MODIFY I and MODIFY II Investigators. Bezlotoxumab for prevention of recurrent Clostridium difficile infection. N Engl J Med. 2017;376:305-317. doi:10.1056/NEJMoa1602615
  9. de Bruyn G, Saleh J, Workman D, et al; H-030-012 Clinical Investigator Study Team. Defining the optimal formulation and schedule of a candidate toxoid vaccine against Clostridium difficile infection: A randomized phase 2 clinical trial. Vaccine. 2016;34:2170-2178. doi:10.1016/j.vaccine.2016.03.028
  10. de Bruyn G, Glover R, Poling TL, et al. Three year follow up for safety and immunogenicity of a candidate Clostridium difficile toxoid vaccine. Presented at: IDWeek 2016. New Orleans, Louisiana; October 26-30, 2016. Poster 746.
  11. Sheldon E, Kitchin N, Peng Y, et al. A phase 1, placebo-controlled, randomized study of the safety, tolerability, and immunogenicity of a Clostridium difficile vaccine administered with or without aluminum hydroxide in healthy adults. Vaccine. 2016;34:2082-2091. doi:10.1016/j.vaccine.2016.03.010
  12. Bezay N, Ayad A, Dubischar K, et al. Safety, immunogenicity and dose response of VLA84, a new vaccine candidate against Clostridium difficile, in healthy volunteers. Vaccine. 2016;34:2585-2592. doi:10.1016/j.vaccine.2016.03.098
  13. Permpoonpattana P, Hong HA, Phetcharaburanin J, et al. Immunization with Bacillus spores expressing toxin A peptide repeats protects against infection with Clostridium difficile strains producing toxins A and B. Infect Immun. 2011;79:2295-2302. doi:10.1128/IAI.00130-11
  14. Ghose C, Kelly CP. The prospect for vaccines to prevent Clostridium difficile infection. Infect Dis Clin North Am. 2015;29:145-162. doi:10.1016/j.idc.2014.11.013
DISCLAIMER
“The C Diff Foundation’s mission is to educate and advocate for Clostridium difficile infection prevention, treatments, support, and environmental safety worldwide.
 
The C Diff Foundation’s organization is comprised of 100% volunteering members who are dedicated to our mission and adhere to the Foundation’s Code of Ethics
which prohibits the endorsement and promotion of products, services, medications, or clinical studies in progress. 
 
All website entries, public presentations, and workshops are to raise C. diff. infection awareness in all areas of the C Diff Foundation’s mission statement, including infection prevention, sepsis, healthcare-associated infections, antimicrobial resistance, antibiotic stewardship and provide education on all the above.”

Seres Therapeutics Announces a New SER-109 Phase 2 Clinical Study (ECOSPOR III) For Patients With Multiple Recurrent C. diff. Infections (CDI’s)

Seres Therapeutics Inc. a leading microbiome therapeutics platform company, announced on March 16th, 2017 plans to initiate a new SER-109 Phase 2 clinical study (ECOSPOR III) in patients with multiply recurrent Clostridium difficile (C. difficile) infection. The ECOSPOR III study design was finalized following a positive Type B meeting with the U.S. Food and Drug Administration (FDA). In a separate announcement today, Seres reported fourth quarter and full year 2016 financial results and provided an update on multiple ongoing microbiome clinical programs.

Seres plans to initiate a new SER-109 clinical study in approximately 320 patients with multiply recurrent C. difficile infection. Study participants will be randomized 1:1 between SER-109 and placebo. To ensure accurate measurement of C. difficile infection, diagnosis of recurrent C. difficile infection for both study entry and for endpoint analysis will be confirmed by C. difficile cytotoxin assay. Patients in the SER-109 arm will receive a total SER-109 dose, administered over three days, approximately 10-fold higher than the dose used in the prior ECOSPOR study. ECOSPOR III will evaluate patients for 24 weeks and the primary endpoint will compare the C. difficile recurrence rate in subjects who receive SER-109 verses placebo at up to eight weeks after dosing. The FDA has agreed that this new trial may qualify as a pivotal study with achievement of a persuasive clinical effect and addressing FDA requirements, including clinical and statistical factors, an adequately sized safety database, and certain CMC parameters.

“We are pleased to have received highly constructive guidance from the FDA regarding further SER-109 clinical development and we plan to initiate a new clinical study as soon as possible,” said Roger J. Pomerantz, M.D., President, CEO and Chairman of Seres. “Our prior SER-109 studies provided important new biological and clinical data that have advanced our pioneering microbiome therapeutic efforts. Based on our learnings and dialogue with the FDA, we believe that we are now positioned to initiate a robust clinical study that may provide the basis for SER-109 approval. There is an urgent need for improved treatments for C. difficile infection, and we believe SER-109 has great potential to address the underlying cause of the disease and become the first approved microbiome therapeutic in this new field of medicine.”

About SER-109

SER-109, an oral capsule, is Seres’ lead Ecobiotic® microbiome therapeutic for the treatment of multiply recurrent C. difficile infection. SER-109 is a biologically sourced consortium of bacterial spores designed to catalyze a shift in a dysbiotic gastrointestinal microbiome to a healthier state.

About Seres Therapeutics

Seres Therapeutics, Inc. is a leading microbiome therapeutics platform company developing a novel class of biological drugs that are designed to treat disease by restoring the function of a dysbiotic microbiome, where the natural state of bacterial diversity and function is imbalanced. The Phase 2 study of Seres’ program SER-109 has been completed in multiply recurrent Clostridium difficile infection. Seres’ second clinical candidate, SER-287, is being evaluated in a Phase 1b study in patients with mild-to-moderate ulcerative colitis (UC). Seres is also developing SER-262, the first ever synthetic microbiome therapeutic candidate, in a Phase 1b study in patients with primary CDI. For more information, please visit www.serestherapeutics.com. Follow us on Twitter @SeresTx.

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 without limitation statements regarding SER-109 development plans, the timing, design, and results of the ECOSPOR III study , the potential for ECOSPOR III to provide different results than the previous ECOSPOR study, the impact analysis of prior clinical studies may have on clinical outcomes, the potential for ECOSPOR III to qualify as a Pivotal Study, dysbiosis as an underlying cause of C. difficile and other diseases.

To Read article in its entirety please click on the link below:

http://finance.yahoo.com/news/seres-therapeutics-initiate-ser-109-110000650.html;_ylt=AwrBT.EHTNBYMRUAv3hXNyoA;_ylu=X3oDMTEzbjcwdjAxBGNvbG8DYmYxBHBvcwM4BHZ0aWQDVUkwMkM0XzEEc2VjA3Ny

 

 

Seres Therapeutics Share Key Findings From Earlier Reported SER-109 Phase 2 Clinical Study Outcome

seres-therapeutics-inc-logo

As published in Seres Therapeutics Press Release  January 31, 2017

 

Findings suggest that both misdiagnosis of C. difficile recurrent infection in some patients, and dosing that may have been suboptimal in certain patients, contributed to the previously reported SER-109 Phase 2 study outcome –

FDA discussions are ongoing regarding a new, redesigned clinical study for SER-109

CAMBRIDGE, Mass., On January 31, 2017 —Seres Therapeutics Inc., a leading microbiome
therapeutics platform company, reported that it has completed in-depth analyses of the previously reported SER-109 Phase 2, eight-week clinical study data in patients with multiply recurrent Clostridium difficile infection.

The company also reported the full, 24-week SER-109 Phase 2 study results and open label extension study data.

“Since obtaining the unexpected SER-109 clinical study results last summer, we have undertaken a comprehensive assessment of the program to understand the reasons for the results,” said Roger J. Pomerantz, M.D., President, CEO and Chairman of Seres.

“We have now identified specific factors that we believe contributed to the Phase 2 results, including issues related to both the accurate diagnosis of C. difficile recurrent infection, and potential suboptimal dosing of certain subjects in the trial. The SER-109 analyses were recently shared with the FDA, and we are actively discussing the design of a new clinical trial for SER-109. There remains a compelling need for an effective, safe, and convenient FDA approved therapy for patients with recurrent C. difficile infection, and this investigation provides insights to guide further clinical development of SER-109.”

Investigation Summary: C. difficile Diagnosis: Analysis was conducted to evaluate both the role of C. difficile diagnostic testing in defining the correct SER-109 Phase 2 study entry population, and in the proper diagnosis of C. difficile recurrences during the study. In the Phase 2 study, 81% of study subjects (72 of 89 subjects) were enrolled based on polymerase chain reaction (PCR) based testing for C. difficile, as well as clinical evaluation. An important and increasingly well-appreciated limitation of PCR testing is that while a positive result indicates that C. difficile cytotoxin genes are present, a positive PCR test does not necessarily indicate thatthe organism is viable and producing disease causing cytotoxins, nor that
C. difficile is the source of clinical symptoms.1

Two separate observations were made pertaining to the effects of discordant results from PCR and cytotoxin assay on the SER-109 trial. The qualifying stool samples evaluated for Phase 2 study entry were not available for retesting for cytotoxin, however, the company was able to retest the samples associated with patients entering the open label extension trial for the presence of the C. difficile cytotoxin and determined that only 44% of samples (15 of 31 subjects) that tested positive by PCR testing also tested positive based on C. difficile cytotoxin assay. These results suggest that a substantial proportion of patients who entered the SER-109 Phase 2 study may have been C. difficile carriers and, therefore, C. difficile infection may not have been the source of the clinical symptoms. In addition, data from this analysis suggest that the use of PCR to measure C. difficile may have overestimated study recurrences in both treatment arms of the Phase 2 trial, further complicating interpretation of study results. This was shown by reanalysis of samples with cytotoxin assay, from patients diagnosed as recurrent in the Phase 2 study. In this retesting, between one quarter andone half of presumed study recurrences may not have been true C. difficile infections leading to pathology.

From the analyses described above, the company believes that misdiagnoses may have occurred both in some patients entering the SER-109 trial, as well as for recurrences diagnosed during the trial.

SER-109 Pharmacokinetics, Pharmacodynamics, & Dosing

The company performed an in-depth analysis to examine SER-109 biological activity in the Phase 2 trial, as measured by microbiome changes in patients and downstream biological effects in the gastrointestinal tract. Results demonstrated a statistically significant increase in the richness of commensal spore-forming bacterial species in patients treated with SER-109, as compared to those receiving placebo. These data demonstrate that SER-109 successfully engrafted and was biologically active in the Phase 2 study. In addition, among those patients with an increased prevalence of specific SER-109 associated bacterial species, a decreasedrate of high confidence recurrences (i.e., recurrences confirmed by C. difficile cytotoxin assay) was demonstrated.

The company also assessed whether the SER-109 dose impacted the degree of microbiome changes observed. All Phase 2 patients received 1 X 10 8 bacterial spores, whereas patients in the prior SER-109 Phase 1b open label study received doses ranging approximately 700-fold, from 3 X 107 to 2 X 109 spores. The company also performed high-resolution whole metagenomics sequencing of stool samples collected from patients in both the SER-109 Phase 1b, as well as the Phase 2 trial as part of this analysis. The analysis indicated that subjects in the open-label Phase 1b study who received a higher dose achieved a significantly greater increase in diversity of commensal spore-former bacteria by 1 week post-treatment, as compared to both Phase 1b and Phase 2 subjects treated with lower doses. These results suggest that the dose used in the SER-109 Phase 2 study may have been suboptimal in certain patients, and may have resulted in a less robust drug effect, contributing to decreased efficacy in Phase 2, as compared to the Phase 1b study.

Much of the SER-109 Phase 2 microbiome-related learnings are based on advancements in the computational analytics and higher resolution whole metagenomics sequencing techniques that Seres is pioneering, and several of these methods were developed after the SER-109 Phase 2 study was designed. Insights obtained from this work may also
benefit Seres’ broad preclinical and clinical microbiome development pipeline.

Analysis of SER-109 Phase 2 Study Clinical Drug Product

The company also conducted a thorough and detailed investigation of the potential impacts of manufacturing and formulation changes implemented in the Phase 2 study. No issues regarding product quality or formulation were identified which would have impacted the Phase 2 study results.

Summary of SER-109 24-Week and Open Label Extension Study Results

The full, 24-week Phase 2 study results continue to demonstrate that SER-109 was generally well tolerated. The most common adverse events associated with SER-109 included diarrhea, abdominal pain and flatulence. The Phase 2 study population represented older individuals, many in poor health, and a high rate of serious adverse events (SAEs) was reported in both study arms. A numerically higher rate of SAEs was observed in the SER-109 arm (15.0% versus 10.3% for placebo), however there was no detectable pattern in the SAEs observed, and none of these were considered to be SER-109 drug-related by the study investigators.

As expected with recurrent C. difficile infection, relatively few additional recurrences occurred beyond 8 weeks, and the 24-week data provides relatively little new information regarding efficacy. Based on 24-week data, five further patients recurred in the SER-109 arm, but three of the five recurrences (60%) were in patients who terminated the trial early, resulting in an imputed recurrence. In the placebo arm, one patient also terminated the trial early, resulting in an imputed recurrence. Early terminations, and loss of patients to follow-up, are common in the long safety follow-up portions of clinical trials.

Phase 2 study subjects who experienced a C. difficile recurrence had the option to enroll in an open label extension study, where they were treated with SER-109 and were followed for an additional 24 weeks. In total, 34 patients entered the open label extension study and 11 patients recurred during the initial 8-week study period, a 32% recurrence rate.

Source:

About Seres Therapeutics:  Seres Therapeutics, Inc. is a leading microbiome therapeutics platform company developing a novel class of biological drugs that are designed to treat disease by restoring the function of a dysbiotic microbiome, where the natural state of bacterial diversity and function is imbalanced. The Phase 2 study of Seres’ program SER-109 has been completed in multiply recurrent C. difficile infection. Seres’ second clinical candidate, SER-287, is being evaluated in a Phase 1b study in patients with mild-to-moderate ulcerative colitis (UC). Seres is also developing SER-262, the first ever synthetic microbiome therapeutic candidate, in a Phase 1b study in patients with primary C. difficile infection. For more information, please visit http://www.serestherapeutics.com. Follow us on Twitter @SeresTx.

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 without limitation statements regarding our SER-109 development plans, the timing, design, and potential results of a new clinical study for SER-109, the potential for a redesigned trial to provide different results, and the impact any analysis may have on clinical outcomes.

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, which may not be available; our limited operating history; the unpredictable nature of our early stage development efforts for marketable drugs; the unproven approach to therapeutic intervention of our microbiome therapeutics; the lengthy and expensive process of clinical drug development, which has an uncertain outcome; potential delays in enrollment of patients which could affect the receipt of necessary regulatory approvals; potential delays in regulatory approval, which would impact the ability to commercialize our product candidates and affect our ability to generate revenue; any fast track or Breakthrough Therapy designation may not lead to faster development, regulatory approval or marketing approval; our possible inability to receive orphan drug designation should we choose to seek it; our reliance on third parties to conduct our clinical trials and the potential for those third parties to not perform satisfactorily; our reliance on third parties to manufacture our product candidates, which may delay, prevent or impair our development and commercialization efforts; our lack of experience in manufacturing our product candidates; the potential failure of our product candidates to be accepted on the market by the medical community; our lack of experience selling, marketing and distributing products and our lack of internal capability to do so; failure to compete successfully against other drug companies; potential competition from biosimilars; failure to obtain marketing approval internationally; post-marketing restrictions or withdrawal from the market; anti-kickback, fraud, abuse, and other healthcare laws and regulations exposing us to potential criminal sanctions; recently enacted or future legislation; compliance with environmental, health, and safety laws and regulations; protection of our proprietary technology; protection of the confidentiality of our trade secrets; changes in United States patent law; potential lawsuits for infringement of third-party intellectual property; our patents being found invalid or unenforceable; compliance with patent regulations; claims challenging the inventorship or ownership of our patents and other intellectual property; claims asserting that we or our employees misappropriated a third-party’s intellectual property or otherwise claiming ownership of what we regard as our intellectual property; adequate protection of our trademarks; ability to attract and retain key executives; managing our growth could result in difficulties; risks associated with international operations; potential system failures; the price of our common stock may fluctuate substantially; our executive officers, directors, and principal stockholders have the ability to control all matters submitted to the stockholders; a significant portion of our total outstanding shares are eligible to be sold into the market; unfavorable or lacking analyst research or reports; and we are currently subject to securities class action litigation. 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 November 10, 2016 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.

Reference:

  1. Polage, C. R., et al. (2015). Overdiagnosis of Clostridium difficile Infection in the Molecular Test Era. JAMA Internal Medicine, 175(11), 1792–1801.

IR or PR Contact:

Carlo Tanzi, Ph.D., Seres Therapeutics, 617-203-3467

Head of Investor Relations and Corporate Communications

Ctanzi@serestherapeutics.com

Summit Therapeutics plc Outlines Phase 3 Program for Novel C. difficile Infection Antibiotic Ridinilazole

summit

Clostridium difficile Treatment – Phase 3 program outline —

 

SUMMIT OUTLINES PHASE 3 PROGRAMME FOR NOVEL CDI ANTIBIOTIC RIDINILAZOLE FOLLOWING FDA AND EMA REGULATORY MEETINGS

Oxford, UK, On 1 February 2017 – Summit Therapeutics plc
the drug discovery and development company advancing therapies for Duchenne muscular dystrophy and C. difficile infection (‘CDI’),  outlines its Phase 3 programme for its novel antibiotic, ridinilazole, following recent regulatory meetings with the US Food and Drug Administration (‘FDA’) and European Medicines Agency (‘EMA’).

With input from the FDA and EMA, Summit intends to design the Phase 3 clinical programme to evaluate superiority of ridinilazole over standard of care in the treatment of C. diffiicle Infection (CDI).

A positive Phase 3 result on superiority has the potential to support the commercial launch of ridinilazole as a differentiated therapy that can both treat initial CDI and reduce disease recurrence.

Mr Glyn Edwards, Chief Executive Officer of Summit commented: “The constructive end of Phase 2 meetings with the US and European regulators have enabled us to design a Phase 3 programme that focuses on evaluating ridinilazole’s superiority over standard of care. This is something we believe would help differentiate our novel class antibiotic from currently marketed CDI treatments and those in late-stage development. Superiority in the combined measure of treatment of initial infection and importantly, reduction in recurrence, could position ridinilazole for front-line treatment of CDI.”
Summit discussed its Phase 3 development programme with the FDA at an End of Phase 2 meeting and through a scientific advice process with EMA. With input from both agencies, the Phase 3 programme is expected to include two trials evaluating ridinilazole as compared to the standard of care, vancomycin, each of which would enrol approximately 700 patients with CDI with the primary endpoint being superiority in sustained clinical response (‘SCR’). Other planned endpoints will include health economic outcome measures. The Phase 3 trial designs are consistent with the successful proof of concept Phase 2 trial, CoDIFy, in which ridinilazole achieved statistical superiority over vancomycin in SCR. SCR is a combined endpoint that measures cure at the end of treatment and a lack of recurrence in the 30 days after treatment. FDA also confirmed that ridinilazole would be eligible for Priority Review based on its QIDP designation.
Mr Edwards continued: “As we continue to evaluate our options to maximize the value of ridinilazole, our stronger financial position following the DMD programme partnership with Sarepta Therapeutics, Inc. means Summit has more time to fully explore all options. These include potentially entering into a collaboration with a third party or securing meaningful non-dilutive funding from government and charitable organizations. In parallel, activities

About Ridinilazole
Ridinilazole is an orally administered small molecule antibiotic that Summit is developing specifically for the treatment of CDI.

In preclinical efficacy studies, ridinilazole exhibited a narrow spectrum of activity and had a potent bactericidal effect against all clinical isolates of C. difficile tested. In a Phase 2 proof of concept trial in CDI patients, ridinilazole showed statistical superiority in sustained clinical response (‘SCR’) rates compared to the standard of care, vancomycin. In this trial, SCR was defined as clinical cure at end of treatment and no recurrence of CDI within 30 days of the end of therapy. Ridinilazole has received Qualified Infectious Disease Product (‘QIDP’) designation and has been granted Fast Track designation by the US Food and Drug Administration. The QIDP incentives are provided through the US GAIN Act and include an extension of marketing exclusivity for an additional five years upon FDA approval.

About Summit Therapeutics
Summit is a biopharmaceutical company focused on the discovery, development and commercialization of novel medicines for indications for which there are no existing or only inadequate therapies. Summit is conducting clinical programs focused on the genetic disease Duchenne muscular dystrophy and the infectious disease C. difficile infection.

Resources:

http://www.summitplc.com/media/press-releases/