ReViral, an antiviral drug discovery and development company developing innovative therapies against Respiratory Syncytial Virus (RSV), has initiated a phase I clinical trial for RV521, its novel orally-active small molecule inhibitor of RSV fusion. RSV infection is an area of significant unmet medical need and RV521 is being developed to treat RSV in patients with severe disease including neonates, the elderly, the immunocompromised and those with underlying cardiovascular or respiratory disease.

Rachel Harland, COO of ReViral, said, “We’re very pleased to have initiated our phase I study on RV521 and eagerly await the demonstration that the drug is suitable for progression to further clinical studies in infected patients.”

Eddy Littler, CEO of ReViral, said, “The progression of RV521 to the clinic is a significant achievement for the Company and marks a major step forward in developing a potential new therapy against RSV. We’re also progressing other exciting early-stage programs against RSV based on different mechanisms than that of RV521."

ReViral’s RV521 phase I clinical trial will evaluate the safety, tolerability, and pharmacokinetics of single ascending and multiple ascending oral doses of RV521, as well as the effect of food on drug absorption. The trial will enroll up to 110 healthy volunteers, including some of Japanese origin. Each year, on average, in the U.S., RSV leads to 57,527 hospitalizations among children younger than five years old; 2.1 million outpatient visits among children younger than five years old; 177,000 hospitalizations and 14,000 deaths among adults older than 65 years. By 2024 current estimates suggest that the worldwide RSV market will be worth over $2 billion (GlobalData, 2016).

In preclinical studies, RV521 has been shown to potently inhibit RSV replication in both cultured human cells and in in vivo models. Moreover, during in vitro studies, only low levels of virus resistance to RV521 were observed. Preclinical studies demonstrated that RV521 has good exposure and low toxicity. Altogether these observations support the potential of RV521 in the treatment of infection in all susceptible populations.