Orphan Drug Designation Granted to RP5063 for Second Pulmonary Indication

Early this morning, Reviva Therapeutics announced that the U.S. Food and Drug Administration (FDA) has granted orphan drug designation to its clinical stage drug candidate RP5063, in development for the treatment of idiopathic pulmonary fibrosis (IPF).

The news comes after it was shown that RP5063 has exhibited robust efficacy in highly recognized translational animal models proven to emulate pulmonary fibrosis (PF) in humans.

Data from preclinical studies show that, in the lungs of bleomycin-induced PF animal models, RP5064 significantly improved survival rate, reduced inflammatory cytokines and tissue scarring, or fibrosis, indicating the drug’s potential for clinically meaningful improvement and stabilization of lung function.

RP5063, a new chemical entity (NCE), has a novel mechanism of multimodal modulation of serotonin and dopamine signaling pathways. Dysfunctional serotonin (5-HT) signaling in the lung results in PF and pulmonary arterial hypertension (PAH). Serotonin signaling involving the 5-HT_2A/2B/7 receptors of the lung has been proven to intermediate vasoconstriction, vascular remodeling, and vascular inflammation, fibrosis and proliferation, all of which are all hallmarks of PF and PAH.

RP5063, is a potent inhibitor of the 5-HT_2A/2B/7 receptors and, thus, weakens these functional changes in a series of animal models proven to mimic PF and PAH conditions in humans.

“Obtaining the Orphan Drug Designation is a significant regulatory milestone as well as a notable achievement for Reviva, since it validates the significant therapeutic potential of RP5063 for the treatment of IPF,” said Laxminarayan Bhat, Ph.D., Founder, President and CEO of Reviva in a press release. “IPF is a devastating disease with limited treatment options and no cure. RP5063, however, provides a novel mechanism of action that has the potential to impact multiple aspects of this disease and, combined with convenient delivery options, RP5063 affords hope to many patients suffering from this debilitating disease.”

In November 2016, the FDA granted Orphan Drug Designation to RP5063 for the treatment of PAH. Reviva has made clear its intentions to initiate Phase 2 clinical trials for both IPF and PAH the “very near future.”

At present, treatment options for IPF are limited, and there is no regulated cure for the condition. Rare Disease Report caught up with Albert Rizzo, M.D. of the Christiana Care Pulmonary and Critical Care Medicine Section at the most recent American Lung Association (ALA) LungFORCE Expo. In the video below, he discusses previous, current and emerging therapies for idiopathic pulmonary fibrosis.

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References:

1. Reviva Pharmaceuticals Receives FDA Orphan Drug Designation for RP5063 for the Treatment of Idiopathic Pulmonary Fibrosis (IPF) [news release]. Sunnyvale, CA: Reviva Pharmaceuticals; April 10, 2018. businesswire.com/news/home/20180409006551/en/Reviva-Pharmaceuticals-Receives-FDA-Orphan-Designation-RP5063