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July 12, 2017

Synspire Pharmaceuticals Novel Glycopolymer Improves Effectiveness of Antibiotics Against Drug-resistant Bacteria Associated with Cystic Fibrosis

BOSTON, Mass. – July 12, 2017 – Synspire Pharmaceuticals, a privately held company developing a new class of inhaled glycopolymer-based therapeutics for the treatment of pulmonary disease, today announced the results of a combination study leveraging polycationic glycopolymers and conventional antibiotics as a potential treatment for pulmonary infection caused by the Burkholderia cepacia complex (Bcc) in patients with cystic fibrosis. The publication, “Novel glycopolymer sensitizes Burkholderia cepacia complex isolates from cystic fibrosis patients to tobramycin and meropenem” is published in PLOS ONE.

“The results published in PLOS ONE demonstrate that our inhaled glycopolymer drug candidate, PAAG, has the potential to significantly enhance the activity of antibiotics that are used for the treatment of lung infections caused by Burkholderia cepacia complex, a relatively uncommon but often fatal infection in cystic fibrosis,” said Synspire Board Member, Shenda Baker, Ph.D. “By breaking down the outer membrane of the bacteria, PAAG makes bacteria more susceptible to antibiotics, even in species that were previously resistant to antibiotic therapy. We believe that our formulated drug SNSP113 using PAAG has the potential to address a key unmet need in these types of infections and to be a new approach to the growing problem of antibiotic resistance in pulmonary indications.”

Chronic pulmonary infection is a characteristic of lung disease in patients with cystic fibrosis (CF). Infections caused by Bcc are particularly difficult to treat because the complex consists of a variety of related strains of bacteria with variable sensitivities to antibiotics, and these strains are naturally multidrug resistant to many common antibiotics. Bcc can acquire resistance easily, making eradication from the lungs of CF patients virtually impossible and leaving patients with few effective therapies. Chronic infection results in progressive loss of lung function, and Bcc is known for its lethality in CF patients.

Synspire is developing a new class of direct-acting glycopolymers, PAAG, as an alternative to traditional antibiotic strategies with lead candidate, SNSP113. The results published in PLOS ONE demonstrate that PAAG rapidly targets bacterial outer membranes and permeabilizes them upon contact, facilitating the potentiation, or enhancement, of antibiotic activity when used in combination with meropenem and tobramycin. The results show that this combination therapy is more effective than combinations with ceftazidime against all Bcc strains and thus has the potential to treat lung infections caused by Bcc in CF patients.

“Unfortunately, Burkholderia cepacia complex infections are some of the most difficult to treat infections among persons with cystic fibrosis and can result in permanent loss of pulmonary function and early death,” said John LiPuma, M.D., Department of Pediatrics and Communicable Diseases, University of Michigan Medical School. “There is a tremendous need for agents that can actively target Bcc and improve patient outcomes”.

In the study, antibiotic synergy was observed with tobramycin and meropenem when used in combination treatment with PAAG. The results demonstrate the ability of PAAG to reduce the Minimum Inhibitory Concentration (MIC) of tobramycin and meropenem below their Clinical and Laboratory Standards Institute (CLSI) breakpoints, making them effective in a clinically acceptable dosage range. Ceftazidime was unable to enhance the activity of tobramycin and meropenem.

Combinations of tobramycin and meropenem, and often with ceftazidime, can be used to treat Bcc infections in CF. Though these antimicrobial agents can cause a reduction in bacterial density, they have shown limited improvement in lung function in CF patients with Bcc, likely because of the diversity of Bcc strains to which they have variable efficacy. PAAG demonstrates broad antibacterial activity across a broad spectrum of drug resistant Bcc and shows synergy with antibiotics in vitro, suggesting its potential for use as a novel therapeutic strategy against highly resistant bacterial infections.

About SNSP113

The company’s lead product, SNSP113, is a first-in-class inhaled glycochemistry-based therapeutic with a broad spectrum mechanism of action intended to target the underlying cascade of events that lead to progressive pulmonary disease or other life-threatening pulmonary conditions, such as nontuberculous Mycobacteria(NTM), Burkholderia cepacia complex (BCC), Pseudomonas aeruginosaor methicillin-resistant Staphylococcus aureus(MRSA). SNSP113 is designed to normalize mucin viscosity and improve mucus transport to increase airway clearance. SNSP113 disrupts the cohesion of bacterial biofilms and interacts with the cell walls of invading bacteria to increase their permeability, reduce their viability and potentiate the efficacy of antibiotics. These actions of SNSP113 lead to a reduction in the inflammatory cascade of neutrophils that can lead to pulmonary damage and fibrosis.  Progressive pulmonary disease leads to overwhelming symptoms, impacts quality of life (QoL) and results in debilitating progressive lung decline. Synspira is expected to initiate SNSP113 Phase 2 trials in 2019.

About Cystic Fibrosis

Cystic fibrosis (CF) is a life-threatening genetic disorder that results in the accumulation of thick, sticky mucus in the lungs, clogging airways and leading to infection and chronic inflammation. Moreover, because of the inability to clear the airways, bacteria colonize and form biofilms that are difficult for antibiotics to penetrate. More than 30,000 people in the United States, and a similar number in Europe, live with cystic fibrosis.