Paratek Receives FDA Affirmation for Design of Proposed Omadacycline Oral-Only Skin Infection Phase 3 Study: Opportunity to Accelerate Access to Broader Oral-Only Markets

  • FDA Affirms Chosen Comparator, Primary Endpoint for Phase 3 Study
  • Study, if Conducted, Would Initiate Following the Reporting of Top-Line Data from IV-to-Oral ABSSSI Phase 3 Study
  • Potential to Include Oral-Only Skin Study in Projected NDA Filing in First Half of 2018

BOSTON, May 10, 2016 (GLOBE NEWSWIRE) -- Paratek Pharmaceuticals, Inc. (Nasdaq:PRTK) announced today that it has received favorable feedback from the U.S. Food and Drug Administration regarding the design of a proposed oral-only Phase 3 study of omadacycline for the treatment of acute bacterial skin and skin structure infections (ABSSSI). In their feedback, the FDA confirmed that the proposed comparator is acceptable and that the proposed study design would meet the requirements established in the FDA’s guidance for ABSSSI studies1. In addition, FDA noted that while the current single Phase 3 intravenous (IV)-to-oral ABSSSI study combined with the Company’s ongoing single Phase 3 IV-to-oral CABP study strategy remains sufficient to support registration for both ABSSSI and CABP indications, this single oral-only ABSSSI study has the potential to be used in combination with the current IV-to-oral ABSSSI study as the basis for a new drug application (NDA) for an ABSSSI indication, if both studies achieve their primary endpoints. The current IV-to-oral ABSSSI study recently completed enrollment, and top-line data is expected as early as the end of June.

The Company currently plans to file its NDA for omadacycline in the first half of 2018 with its IV-to-oral ABSSSI registration study and its IV-to-oral CABP registration study, both of which are being conducted under Special Protocols Assessments with the FDA. A successful outcome in each of these two studies (“1+1” strategy) would support the approval for both indications for the once-daily oral and IV formulations of omadacycline. The prospective oral-only skin registration study has the potential to be completed in time to be included in the projected NDA filing which would then support approval for an oral-only skin indication concurrent with the IV-to-oral indications in both skin and pneumonia. If approved, an oral-only indication would allow for promotion in the broad community setting representing significant potential value to the Company and prospective partners. The proposed oral-only skin study would also support an EMA filing and represent a second registration study for ABSSSI in Europe.

“This confirmatory FDA feedback on our proposed oral-only Phase 3 registration study in ABSSSI establishes a potential path to an oral-only skin indication on our currently projected “1+1” NDA timeline,” said Evan Loh, M.D., President and Chief Medical Officer, Paratek. “Given the rapid enrollment in our pivotal IV-to-oral Phase 3 skin study and the significant interest among investigators in oral omadacycline, we believe that an oral-only skin study could enroll quickly. We are preparing for potential initiation of this oral-only skin study in the quarter following announcement of the top-line data on our IV-to-oral registration ABSSSI study, which remains on-track for as early as the end of June 2016. The initiation of this new clinical study however will be determined in part with a view towards preserving our currently projected cash runway.”

The proposed randomized (1:1), active comparator-controlled, double-blind, double-dummy, Phase 3 study would compare oral-only, once-daily omadacycline to oral-only, twice-daily linezolid for the treatment of adult subjects with ABSSSI that is known or suspected to be due to a Gram-positive pathogen(s). The study is powered to demonstrate non-inferiority (NI) of the primary efficacy outcome of Early Clinical Response (at 48 to 72 hours following the first dose of test article) in the modified Intent-to-Treat (mITT) population. In addition, the study would also be adequately powered to demonstrate NI for the post-treatment evaluation (PTE) endpoint, often referred to as the “Test of Cure” assessment, the primary endpoint for approval by the EMA. The overall design is consistent with the FDA-approved Special Protocol Assessment for the pivotal IV-to-oral switch omadacycline study in ABSSSI (Protocol PTK0796-ABSSSI-1108), which completed enrollment in March 2016.

About Paratek Pharmaceuticals, Inc.
Paratek Pharmaceuticals, Inc. is a biopharmaceutical company focused on the development and commercialization of innovative therapies based upon its expertise in novel tetracycline chemistry. Paratek's lead product candidate, omadacycline, is the first in a new class of tetracyclines known as aminomethylcyclines, with broad-spectrum activity against Gram-positive, Gram-negative and atypical bacteria. Paratek completed enrollment in a Phase 3 registration study in ABSSSI in March 2016 to determine the efficacy and safety of omadacycline compared to linezolid. Top-line data from this study is expected to be available as early as the end of June 2016. A Phase 3 registration study for CABP comparing omadacycline to moxifloxacin was initiated in November 2015 and top-line data is expected as early as the third quarter of 2017. Paratek initiated a Phase 1b study of omadacycline in urinary tract infections in May 2016. Omadacycline has been granted Fast Track status by the U.S. Food and Drug Administration.

Omadacycline is a new once-daily oral and IV, well-tolerated broad-spectrum antibiotic being developed for use as empiric monotherapy for patients suffering from serious community-acquired bacterial infections, such as acute bacterial skin and skin structure infections, community acquired bacterial pneumonia, complicated urinary tract infections (cUTI), and other community-acquired bacterial infections, particularly when antibiotic resistance is of concern to prescribing physicians.

Paratek's second Phase 3 product candidate, sarecycline, is a new once-daily oral tetracycline-derived compound for the potential treatment of acne and rosacea in the community setting. Sarecycline is designed to be a well-tolerated, once-daily oral, narrow spectrum antibiotic with anti-inflammatory properties. Allergan owns the U.S. rights for the development and commercialization of sarecycline. Paratek retains all ex-U.S. rights. Allergan initiated two identical Phase 3 registration studies in December 2014 for sarecycline for the treatment of moderate to severe acne vulgaris. Top line data is expected from these studies in the second half of 2016.

For more information, visit The information contained on, or that may be accessed through, Paratek’s website is not incorporated by reference into, and is not a part of, this document.

Forward Looking Statement
Certain statements in this press release, including Paratek’s statements regarding the projected availability of top-line data from the Phase 3 clinical trials of omadacycline and sarecycline, as well the projected timing of our NDA filing for omadacycline are forward-looking statements. These forward-looking statements are based upon Paratek's current expectations and involve substantial risks and uncertainties. These risks and uncertainties include, but are not limited to: (i) unexpected results may cause the designs of the clinical trials to change, or the projected timelines of the trials to be extended, (ii) unexpected decline in the rates of patient enrollment in the clinical trials, (iii) unforeseen adverse effects experienced by patients resulting in a clinical hold, (iv) failure of patients to complete clinical trials, (v) risks related to regulatory oversight of the trials, (vi) the need for substantial additional funding to complete the development and commercialization of product candidates and (vii) risks that data to date and trends may not be predictive of future results. These and other risk factors are discussed under "Risk Factors" and elsewhere in Paratek's Annual Report on Form 10-K for the year ended December31, 2015 and Paratek's other filings with the Securities and Exchange Commission. Paratek expressly disclaims any obligation or undertaking to update or revise any forward-looking statements contained herein.

1 Guidance for Industry Acute Bacterial Skin and Skin Structure Infections: Developing Drugs for Treatment

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Source:Paratek Pharmaceuticals