Summit Therapeutics: Editorial Published in Future Microbiology Advocating for Innovation in Antibiotic Development

Summit Announces Publication of Editorial in Future Microbiology Advocating for Innovation in Antibiotic Development to Drive Stewardship Focus on Improving Patient Outcomes

• New Classes of Targeted Antibiotics Support Stewardship and could Combat Resistance

Oxford, UK, and Cambridge, MA, US, 18 September 2019 – Summit Therapeutics plc (NASDAQ: SMMT, AIM: SUMM) today announced the publication of a Personal Perspective entitled “Combating Resistance While Maintaining Innovation: The Future of Antimicrobial Stewardship” in the journal Future Microbiology. The paper calls for innovation in the development of antimicrobial products to drive antibiotic stewardship programmes (‘ASPs’) to focus on improving patient outcomes.

“Antimicrobial stewardship calls for the appropriate use of antibiotics to optimise patient outcomes by ensuring the right drug, right dose and duration are administered,” said Professor Cornelius Clancy, Director of the XDR Pathogen Lab at the University of Pittsburgh. “Through our publication, we are advocating for the focus to be on measures directly connected to the patients and on improving their care. I believe evolving the current stewardship programmes will be incentivised by the emergence of innovative antimicrobials designed for specific infectious diseases.”

The concept of antibiotic stewardship arose in the 1970s in response to the emergence of antibiotic resistance. Its purpose was to ensure judicious antibiotic use to optimise clinical outcomes for patients. However, a recent Infectious Disease Society of America (‘IDSA’) survey indicated that 87% of hospital providers in the US considered reducing antibiotic costs a major driver in their ASPs, despite antibiotic cost not being in the definition of antibiotic stewardship. With ASPs to be implemented in all US acute care hospitals by 2020, and numerous stewardship initiatives in Europe, the publication outlines why it is crucial that ASPs are optimised to focus on measures such as resistance, mortality, hospital length of stay and readmission rates. This could encourage use of innovative antibiotics to improve patient outcomes and reduce the total burden of bacterial infections on healthcare systems.

“Our approach to antibiotic drug development aims to end the perception that new antibiotics are ‘break-in-emergency’ treatments. Our lead antibiotic, ridinilazole, is being developing for C. difficile infection, where current treatments fail in about a third of cases. Ridinilazole is a new class antibiotic with a new mechanism of action and our landmark Phase 3 is a superiority clinical trial designed to support the value of its use front-line. Our approach shows how innovation can closely align with good stewardship as we seek to achieve better outcomes for patients,” said Dr David Roblin, President of R&D of Summit.

Targeted spectrum antibiotics have the potential to significantly enhance antibiotic stewardship. With the advances in rapid diagnostics, targeted antibiotics could be developed as front-line treatments for a specific infection, potentially showing clear benefits in patient outcomes over the current standard of care, while allowing use of existing broad-spectrum agents to be reserved. In addition, new classes of antibiotics are likely to circumvent existing resistance mechanisms compared to analogues of current classes where antibiotic resistance already exists.

About Summit Therapeutics

Summit Therapeutics is a leader in antibiotic innovation. Our new mechanism antibiotics are designed to become the new standards of care for the benefit of patients and create value for payors and healthcare providers. We are currently developing new mechanism antibiotics for infections caused by C. difficile, N. gonorrhoeae and Enterobacteriaceae and are using our proprietary Discuva Platform to expand our pipeline. For more information, visit www.summitplc.com and follow us on Twitter @summitplc.

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