ReViral Announces Grant of Key US Composition of Matter Patent for Their Respiratory Syncytial Virus Inhibitor Programme

Patent claims RSV fusion protein inhibitors as medicines including lead pipeline candidate, RV521; patent nominally expires in 2035 (unextended)

April 8, 2019 12:00 UTC
  • Patent claims RSV fusion protein inhibitors as medicines including lead pipeline candidate, RV521; patent nominally expires in 2035 (unextended)
  • The counterpart to this patent has been issued in Europe and is pending prosecution in other key territories
  • Patent significantly adds to IP portolio protecting Riviral’s differentiated pipeline
  • Company continues to progress RV521 into international, pediatric Phase IIa clinical trials during 2019

LONDON--(BUSINESS WIRE)-- ReViral Ltd., a clinical-stage company focused on developing novel, anti-viral compounds that target respiratory syncytial virus (RSV), today announced that the the United States Patent and Trademark Office (USPTO) recently granted patent US10,106,539 entitled “Spiro-Indolines for the Treatment and Prophylaxis of Respiratory Syncytial Virus Infection (RSV)”. This composition of matter patent claims certain inhibitors of the fusion protein of the respiratory syncytial virus (RSV), including RV521, the Company’s lead pipeline asset. The counterpart to this patent, EP3204375, has also been issued in Europe.

“The grant of this important patent in the US and Europe protects certain RSV fusion protein inhibitors discovered by ReViral, including lead pipeline asset RV521, and underscores the novelty of our RSV pipeline,” said Dr Eddy Littler, CEO of ReViral. “We look forward to progressing RV521 into international, pediatric phase II clinical trials this year, with the ultimate goal of bringing new, effective treatments for RSV to patients.”

ReViral is progressing its lead drug candidate (RV521), a highly potent and orally bioavailable potential treatment for RSV infections. Pre-clinical and clinical studies have shown that RV521 is a best-in-class inhibitor of RSV in adult volunteers. RV521 is now poised to enter an international multicentre Phase IIa pediatric trial. This study will be followed by additional trials in adult stem cell transplant patients.

RSV is one of the most important respiratory pathogens, with 30 million infections and an estimated 200,000 deaths worldwide annually in children under five years alone. There are currently no approved RSV vaccines available, and there is an urgent need for improved therapeutics for this indication.

Notes to Editors

About ReViral

ReViral is a clinical-stage company focused on developing novel, anti-viral compounds that target respiratory syncytial virus (RSV). Founded in 2011, ReViral has an experienced R&D leadership team with a successful track record in antiviral drug discovery and development. The company has developed a novel antiviral programme targeting RSV fusion with highly potent, orally bioavailable inhibitors, strong drug-like characteristics and good pharmacokinetic properties offering versatility in the route of administration. The lead candidate RV521 completed a Phase IIa study in adult volunteers showing high potency and excellent safety. The company also has an RSV replication programme at an earlier stage of development and plans to expand its pipeline. In August 2018, ReViral completed a $55 million Series B funding round from a group of leading venture capital investors jointly led by New Leaf Venture Partners and Novo Ventures, part of Novo Holdings A/S, with additional new investment from Perceptive Advisors. Existing investors Andera Partners, OrbiMed and Brace Pharma Capital also participated in the fundraise.

About RV521

RV521 is an orally available small molecule antiviral fusion inhibitor being evaluated for the treatment of RSV. RV521 blocks RSV replication by inhibiting RSV F-mediated fusion of RSV to the host cell. In 2018, RV521 generated positive results in a Phase IIa RSV challenge study in healthy adult volunteers, producing statistically significant reductions in viral load and clinical symptoms. In Phase I clinical studies RV521 showed excellent exposure with no serious adverse events. Pre-clinical toxicity tests in adult and juvenile species showed RV521 to have an excellent safety profile with an attractive margin over therapeutic doses.

About Respiratory Syncytial Virus (RSV)

RSV is a pathogen that infects the human respiratory tract, potentially leading to bronchiolitis and pneumonia. While most (but not all) otherwise healthy people recover from the virus, there is an increased risk of severe disease and death in premature infants, individuals with certain pulmonary conditions, the elderly and those who are immune suppressed. Globally RSV is responsible for more than 30 million infections every year and as many as 200,000 infant deaths. An estimated 2-3% of all infants under 2 years of age are hospitalised with RSV.

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ReViral Ltd
Eddy Littler, CEO
T: +44 (0) 1438 906761

FTI Consulting (PR Advisors to ReViral)
Irma Gomez-Dib (US) +1 212 850 5761
Simon Conway (UK) +44 20 3727 1000

Source: ReViral Ltd.