– Rapid Declines in LDH and Near-Complete Inhibition of Hemolytic Activity

– Review of Initial Safety and Efficacy Data Enables Opening of Eculizumab Switch Cohort

CAMBRIDGE, MA, USA I June 27, 2017 I Ra Pharmaceuticals, Inc. (NASDAQ:RARX) today announced initial data from the Company’s global Phase 2 clinical program evaluating RA101495 for the treatment of paroxysmal nocturnal hemoglobinuria (PNH). Ra Pharma is a clinical stage biopharmaceutical company focusing on the development of next-generation therapeutics for the treatment of complement-mediated diseases and is developing RA101495 as a novel, subcutaneously-administered (SC) inhibitor of complement component 5 (C5).

 

The dose-finding Phase 2 clinical program is designed to evaluate the safety, tolerability, preliminary efficacy, pharmacokinetics (PK) and pharmacodynamics (PD) of RA101495 in patients with PNH (see About RA101495 Phase 2 Clinical Program, below). Currently, the study has three eculizumab-naïve patients enrolled, of which two have completed seven weeks of follow-up and are included in the Company’s initial data set. Review of these initial data enables the opening of Cohort B, which will enroll patients switching from eculizumab, the current standard of care, for PNH.

Notable findings include:

  • No safety or tolerability concerns identified; no injection site reactions
  • Near-complete inhibition of hemolytic activity
  • Rapid declines in lactate dehydrogenase (LDH); mean LDH at Week 7 = 1.6X upper limit of normal (ULN)
  • 100% compliance with once daily, subcutaneous self-administration

At the week 6 visit, one patient reported recurrence of PNH symptoms associated with hemoglobinuria and an elevated LDH level. This episode of breakthrough hemolysis occurred in the setting of an intercurrent illness, judged by the investigator to be most likely due to a viral infection. The episode was transient and resolved rapidly with LDH levels returning to 1.3X ULN by the week 7 visit with resolution of hemolytic symptoms.

“Currently, the only approved treatment for PNH is a monoclonal antibody which must be administered intravenously every two weeks by healthcare professionals,” said Principal Investigator Anita Hill, M.D., PhD, MRCP, FRCPath, Consultant Haematologist for Leeds Teaching Hospitals NHS Trust, UK, and Lead Clinician for the National PNH Service in England. “As a once daily, self-administered, subcutaneous therapy, RA101495 has the potential to offer a convenient option for patients with PNH. These initial data on eculizumab-naïve patients are encouraging, and I look forward to seeing data from patients switching from eculizumab to RA101495.”

“We are pleased by the initial results from this study, our first in PNH patients, whose primary purpose is to gain important safety, preliminary efficacy, PK and PD data in the target patient population,” said Doug Treco, PhD, President and Chief Executive Officer of Ra Pharma. “These data will help inform dose selection for pivotal trials and will help refine our clinical development strategy. We look forward to giving you an update on our progress around year-end.”

 
Conference Call & Webcast
       
Date:     Tuesday, June 27, 2017
       
Time:     8:00 a.m. ET
       
Telephone Access:     Domestic callers, dial 844-419-1655,
      International callers, dial 216-562-0467,
      Reference the Ra Pharmaceuticals conference call;
       
Telephone Access:     Go to the Investor Relations section of the Ra Pharma website (http://ir.rapharma.com/phoenix.zhtml?c=254447&p=irol-calendar) and follow instructions for accessing the live webcast. Please connect to the website at least 15 minutes prior to the start of the conference call to ensure adequate time for any software download that may be necessary.
       

About RA101495

Ra Pharma is developing RA101495 for paroxysmal nocturnal hemoglobinuria (PNH), refractory generalized myasthenia gravis (rMG), and lupus nephritis (LN). The product is designed for convenient, once daily SC self-administration. RA101495 is a synthetic, macrocyclic peptide discovered using Ra Pharma’s powerful proprietary drug discovery technology. The peptide binds complement component 5 (C5) with sub-nanomolar affinity and allosterically inhibits its cleavage into C5a and C5b upon activation of the classical, alternative or lectin pathways. By binding to a region of C5 corresponding to C5b, RA101495 also disrupts the interaction between C5b and C6 and prevents assembly of the membrane attack complex (MAC). This activity defines an additional, novel mechanism for the inhibition of C5 function. In Phase 1 studies, dosing of RA101495 was well tolerated in healthy volunteers and demonstrated sustained and near complete suppression of hemolysis and complement activity. To learn more about RA101495, please visit: http://rapharma.com/pipeline/ra101495/.

About RA101495 Phase 2 Clinical Program

The global, dose-finding Phase 2 program is designed to evaluate the safety, tolerability, preliminary efficacy, pharmacokinetics and pharmacodynamics of RA101495 in patients with PNH. The study will evaluate RA101495 in three cohorts. Cohort A includes eculizumab-naïve patients, Cohort B includes patients switching from eculizumab to RA101495 and a third cohort includes patients who are currently treated with eculizumab but have evidence of an inadequate response. Patients in all three cohorts will be eligible for a long-term extension study following the completion of the initial 12-week studies. The primary efficacy endpoint is change in lactate dehydrogenase from baseline to the mean level from Week 6 to week 12.

About Ra Pharmaceuticals

Ra Pharmaceuticals is a clinical stage biopharmaceutical company focusing on the development of next-generation therapeutics for complement-mediated diseases. The Company discovers and develops peptides and small molecules to target key components of the complement cascade. For more information, please visit: www.rapharma.com.

SOURCE: Ra Pharmaceuticals