Reviva announced that the FDA has granted Orphan Drug Designation for RP5063, an investigational agent for the treatment of idiopathic pulmonary fibrosis.

Dysfunctional serotonin signaling in the lung is thought to cause pulmonary fibrosis and pulmonary arterial hypertension (PAH). The mechanism of RP5063 involves multimodal modulation of serotonin and dopamine signaling pathways. As a strong inhibitor of the 5-HT2A/2B/7 receptors, RP5063 has shown to attenuate these changes in a series of animal models.

RP5063 was evaluated in translational animal models emulating pulmonary fibrosis where it demonstrated robust efficacy. It significantly increased survival rate, decreased inflammatory cytokines and fibrosis in the lungs of bleomycin-induced pulmonary fibrosis animal model, showing potential for clinically meaningful improvement and lung function stabilization.