NEW HAVEN, Conn.--(BUSINESS WIRE)--Rib-X Pharmaceuticals, Inc., today announced the initiation of a Phase 3 clinical trial evaluating delafloxacin, the company’s lead antibiotic, in patients with acute bacterial skin and skin structure infections (ABSSSI). Delafloxacin is a novel fluoroquinolone antibiotic with intravenous (IV) and oral formulations that have demonstrated a favorable safety and efficacy profile in prior studies against infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and a broad array of Gram-positive and Gram-negative bacteria, many of which were resistant to other quinolones.
The PROCEED (PROve Clinical Efficacy and Effect of Delafloxacin) Phase 3 study is a multi-center, randomized, double-blind, active-controlled study to evaluate the efficacy and safety of delafloxacin 300 mg IV every 12 hours compared to vancomycin 15 mg/kg plus aztreonam 2 g IV every 12 hours. The study includes clinical and microbiological endpoints to assess the efficacy of the treatment regimens. The study design has been agreed upon in a Special Protocol Assessment with the FDA and with the EMA.
“The data to date have shown that delafloxacin has a favorable safety profile in nearly 1,500 subjects, and it has outperformed current standards of care against drug-resistant bacteria, including MRSA,” commented Mary T. Szela, Chief Executive Officer of Rib-X. “We believe this study will further demonstrate the differentiated profile and strength of delafloxacin in treating ABSSSI and we look forward to expanding the application of delafloxacin to additional clinical indications in future studies. In addition, we continue to advance our preclinical and discovery programs toward the clinic, including our late-preclinical RX-04 program.”
“The initiation of this trial marks an important milestone for our Company as we advance our lead clinical asset towards potential commercialization,” said Eugene Sun, Rib-X’s Executive Vice President, Research and Development. “This is the first of two planned Phase 3 trials for delafloxacin in ABSSSI, and we expect to initiate the second Phase 3 with our oral formulation later this year or in early 2014.”
About Delafloxacin:
Delafloxacin is being developed for use as an effective and convenient first-line antibiotic initially in hospitals prior to the availability of a specific diagnosis. Delafloxacin has the potential to offer broad spectrum coverage as a monotherapy, including for methicillin-resistant Staphylococcus aureus (MRSA), with both intravenous (IV) and oral formulations. With the exception of Zyvox® (linezolid), all other currently approved treatments for MRSA offer only IV delivery. In addition to strong Gram-positive potency, delafloxacin has shown excellent in vitro activity against susceptible Gram-negative bacteria. In a successful Phase 2b study, delafloxacin met or exceeded primary and secondary efficacy endpoints evaluated in comparison to Zyvox, with and without aztreonam, and vancomycin, with and without aztreonam, including the new objective endpoints included in guidance from the US Food and Drug Administration (FDA) for ABSSSI.
The Food and Drug Administration (FDA) designated delafloxacin as a Qualified Infectious Disease Product (QIDP) for the indications of acute bacterial skin and skin structure infections (ABSSSI) and community-acquired bacterial pneumonia (CABP). The QIDP designation enables Rib-X to benefit from certain incentives for the development of new antibiotics, including an additional five years of market exclusivity, priority review and eligibility for fast-track status. Delafloxacin has been evaluated in four Phase 2 trials where it has shown promising results for the treatment of lung infections, including pneumonia and bronchitis, and skin infections. Rib-X is developing both IV and oral formulations of delafloxacin to enable patients who begin IV treatment in the hospital setting to transition to oral dosing for home-based care, offering the potential to increase patient convenience, lower the overall cost of treatment and reduce the length of hospital stays. These attributes, combined with delafloxacin’s safety profile and reduced probability of resistance, demonstrate the potential of delafloxacin to become a new standard of care for first-line treatment of serious infections.
About Rib-X:
Rib-X Pharmaceuticals, Inc. is a biopharmaceutical company developing new antibiotics to provide superior coverage, safety and convenience for the treatment of serious and life-threatening infections. The Company's proprietary drug discovery platform is based on Nobel Prize-winning science and provides an atomic-level, three-dimensional understanding of interactions between drug candidates and their bacterial targets to enable the design of antibiotics with enhanced characteristics. Rib-X’s lead program is delafloxacin, an enhanced spectrum IV/oral antibiotic intended for use as first-line monotherapy to treat multiple bacterial diseases, which completed a Phase 2b clinical trial for the treatment of acute bacterial skin and skin structure infections. The Company's pipeline also includes its preclinical RX-04 program targeting multidrug-resistant and extremely-drug-resistant Gram-negative infections and other discovery stage anti-infective programs. Rib-X is privately held and backed by Vatera Healthcare Partners and Warburg Pincus, among others. For more information, please visit www.rib-x.com.