NEW HAVEN, CT, USA I September 19, 2015 I Melinta Therapeutics, a privately held company developing novel antibiotics to treat bacterial infections, today announced in vitro results demonstrating delafloxacin’s activity against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis, three bacteria commonly associated with respiratory tract infections. Delafloxacin is an investigational fluoroquinolone in late-stage development for the treatment of acute bacterial skin and skin structure infections (ABSSSI). In clinical trials, delafloxacin is being tested in both IV and oral formulations. Delafloxacin has been studied in over 2,000 subjects to date in 27 clinical studies.

In this study, delafloxacin was tested against more than 500 S. pneumoniae, H. influenzae and M. catarrhalis isolates from around the United States and Europe, including S. pneumoniae isolates that had shown resistance to levofloxacin, penicillin and ceftriaxone. Delafloxacin’s activity was compared to antibiotics covering multiple classes including the currently marketed quinolones ciprofloxacin, levofloxacin and moxifloxacin. Among these antibiotics, delafloxacin was the most potent compound tested against S. pneumoniae, H. influenza and M. catarrhalis. Importantly, delafloxacin was shown to be active against all resistant S. pneumoniae isolates and was not affected by beta-lactamase status in H. influenza and M. catarrhalis.

“The strong in vitro activity of delafloxacin that we observed in this study, particularly against multi-drug resistant pathogens, suggests that further clinical study in respiratory tract infections is warranted,” stated Eugene Sun, MD, interim Chief Executive Officer and EVP of R&D of Melinta Therapeutics. “Hospital-treated community-acquired pneumonia, for example, remains a significant unmet need, especially among the elderly and immunocompromised.”

Complete results from this study are being presented at the 55th annual Interscience Conference of Antimicrobial Agents and Chemotherapy (ICAAC), which is being held September 17-21, 2015 in San Diego, CA. In addition to the above results, Melinta will be presenting four other posters of preclinical and clinical studies which evaluated the safety and activity of delafloxacin. In addition, Melinta will present progress made towards the development of a novel antibiotic class with the ability to cover multi- and extremely-drug-resistant Gram-negative pathogens from the Company’s ESKAPE Research Program (ESKAPE is an acronym for 6 pathogens with growing multidrug resistance virulence: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumonia, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species and Escherichia coli).

In total, Melinta will be presenting the following six posters:

September 18, 2015 from 12:00 PM – 2:00 PM PT

  • Pharmacodynamic (PD) Assessment of Delafloxacin (DFX) against Streptococcus pneumoniae, Methicillin-resistant Staphylococcus aureus (MRSA), and Klebsiella pneumoniae in a Murine Lung Infection Model. Poster A-050.

September 19, 2015 from 11:00 AM – 1:00 PM PT

  • In Vitro Activity of Delafloxacin Tested against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Poster C-549.
  • Susceptibility of Common Clostridium difficile PCR Ribotypes to Delafloxacin and Seven Comparator Antimicrobials. Poster C-574.
  • Determination of the Activity of Novel Analogues of RX-P873 against Gram-negative Bacteria. Poster F-764.

September 20, 2015 from 11:00 AM – 1:00 PM PT

  • Assessment of Phototoxicity Potential of Delafloxacin in Healthy Male and Female Subjects: a Phase 1 Study. Poster F-1199.
  • Characterization and In Vitro Activity of Delafloxacin (DLX) Against Isolates from a Phase 3 Study of Acute Bacterial Skin and Skin Structure Infections (ABSSSI). Poster F-1197.

About Delafloxacin

Delafloxacin is an investigational anionic fluoroquinolone antibiotic currently in Phase 3 clinical development for hospital-treated skin infections, known as acute bacterial skin and skin structure infections (ABSSSI). The PROCEED studies (studies 302 and 303) are Phase 3, multicenter, randomized, double-blind, active-controlled trials to evaluate delafloxacin compared with vancomycin + aztreonam for the treatment of patients with ABSSSI. The PROCEED studies are evaluating delafloxacin in both IV and oral formulations. Delafloxacin has been designated a Qualified Infectious Disease Product (QIDP) for both ABSSSI and community-acquired bacterial pneumonia by the U.S. Food and Drug Administration.

About Melinta Therapeutics    

Melinta Therapeutics, Inc. is dedicated to saving lives threatened by the global public health crisis of bacterial infections through the development of novel antibiotics that provide new and better therapeutic solutions. Melinta is rapidly progressing its late-stage investigational antibiotic, delafloxacin, which is currently in Phase 3 development for acute bacterial skin and skin structure infections (ABSSSI). Melinta is committed to developing, through the application of Nobel Prize-winning science, a new class of antibiotics designed to overcome the multi- and extremely-drug-resistant pathogens for which there are few to no options, known collectively as ESKAPE pathogens, which cause the majority of life-threatening hospital infections.

Melinta Therapeutics is privately held and backed by Vatera Healthcare Partners among other private investors. The company is headquartered in New Haven, CT with offices in Lincolnshire, IL. Visit for more information.

SOURCE: Melinta Therapeutics