LONDON--(BUSINESS WIRE)--ReViral, a UK based biotechnology company focused on the discovery and development of antivirals for respiratory syncytial virus (RSV), announced today top-line safety and pharmacokinetic (PK) data from the Phase 1 single and multiple ascending dose (SAD and MAD) trial of RV521. RV521 is a novel oral fusion inhibitor in development for the treatment and prevention of RSV infections. It specifically inhibits RSV replication by blocking viral entry and cell to cell spread (syncytium formation). RV521 demonstrates potent antiviral activity across multiple strains of RSV in vitro and represents a step forward in the development of effective therapeutics for this serious and potentially life-threatening infection.
Results from the trial indicated that RV521 was well tolerated at all dose levels; there were no significant treatment-related adverse events and no adverse changes in electrocardiograms or clinical laboratory values.
"This trial represents a significant step in the development of RV521 as an effective first-line antiviral therapy for RSV infection in infants and the elderly. We dosed a total of 48 subjects in the trial with good tolerance at all doses. Antiviral levels of RV521, more than 3xEC90, were rapidly achieved and maintained in the plasma," stated Eddy Littler, PhD, Chief Executive Officer of ReViral.
ReViral also conducted a blinded multiple ascending dose (MAD) study in the UK evaluating the safety and PK of RV521 on three cohorts of healthy volunteers (175, 250 and 350 mg of RV521) dosed orally twice a day for five consecutive days. Each of the dose cohorts consisted of six subjects who received RV521 and two who received a placebo. There were no significant adverse events reported in any subject at any dose level. Optimal RV521 exposure was rapidly achieved with an excellent half-life and was consistent with predicted values modelled from the SAD data.
“The results of our Phase 1 clinical trials show that RV521 is potentially a best in class inhibitor of RSV with good exposure at low doses and no significant adverse events. I am very pleased that we have shown that RV521 can be administered simply by the oral route as, during infection, RSV causes a large amount of mucus to be produced limiting other methods of delivery. We are looking forward to starting our Phase 2a study next quarter” stated Ken Powell, PhD, Chairman of ReViral.
Notes to Editors
ReViral is an antiviral drug discovery, and development company focused on novel treatments for diseases caused by the 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 route of administration. ReViral’s Phase 1 clinical trial will include Japanese volunteers. The Japanese pharmaceutical market is the second largest behind the US, and information obtained from Japanese volunteers is essential to ensure rapid future development.
In 2012 ReViral won a significant Seeding Drug Discovery Award from the Wellcome Trust to develop its RSV fusion inhibitors to completion of IND filing. The company also has an RSV replication programme at an earlier stage of development and plans to expand its pipeline. In September 2015, ReViral completed a $21 million Series A funding round from a group of leading venture capital investors including Edmond de Rothschild Investment Partners, OrbiMed, and Brace Pharma Capital.
RSV causes substantial mortality and morbidity among infants and children under the age of 2 years, with an estimated annual incidence >3.5 million in the USA. Worldwide mortality rates in children under five years of age are estimated at 200,000, and there are infant deaths occurring in the US every year with reported numbers ranging from 500-4,500.
Bronchiolitis, due to RSV, is the most common cause of hospitalisation among infants during the first 12 months of life, and an estimated 310,000 cases of children under five are hospitalised per annum in the United States and EU. There is also a strong association between RSV infection in infants and recurrent wheezing, as well as reported increased rates of asthma, later in childhood. Infection in young adults also occurs, but both the frequency and severity are lower than that observed in young children.
RSV causes a significant disease burden in the elderly particularly those with respiratory or cardiac co-morbidities. RSV is a leading cause of morbidity and mortality in this population, with an estimated 175,000 hospitalisations and 10,000 deaths in the US annually.
RSV poses a serious threat to adult patients who are immunosuppressed following lung or haemopoietic stem cell transplantation (SCT) with a reported 10-17% of SCT patients contracting RSV. Adults with chronic respiratory disease are a high-risk population, with over 25% of patients with chronic obstructive pulmonary disease (COPD) diagnosed with RSV during exacerbations, which can lead to serious often fatal pneumonia.