A potentially best-in-class candidate for the prevention and treatment of COVID-19

UNION is developing niclosamide, a small molecule with potent and broad-spectrum anti-infective properties, initially in COVID-19 but with broader potential in other respiratory infections. Niclosamide has a host-targeting dual mode-of-action (MoA), which reduces viral replication in cells and helps cells to clear viruses through an increase in autophagic flux. Niclosamide has demonstrated a 40-fold higher in vitro potency against SARS-CoV-2 compared to remdesivir in preclinical studies undertaken during 2020 and has been demonstrated in vitro to be effective against a range of COVID-19 variants.

Niclosamide is a salicylanilide introduced into clinics in the early 1960s as an oral treatment for tapeworm infections and is currently marketed in several European and developing countries. Niclosamide in its oral form has poor systemic availability limiting its use as a treatment for respiratory viruses. Therefore, UNION has developed a concentrated liquid formulation of niclosamide that allows for delivery as a nasal spray to the upper respiratory tract (niclosamide nasal spray). For respiratory infections, such as COVID-19, this allows for a local delivery of niclosamide directly to the site of infection, either as a potential treatment or, prior to infection, as a prophylactic agent.