Antipsychotic Agent with Potential as PAH Treatment Named Orphan Drug by FDA
The U.S. Food and Drug Administration (FDA) has designed Reviva Pharmaceuticals’ RP5063 an Orphan Drug as a potential treatment of pulmonary arterial hypertension (PAH), providing the company with developmental and testing assistance.
“We are pleased to receive Orphan Drug Designation for RP5063, which emphasizes the significant need for new mediations for patients suffering from PAH,” Laxminarayan Bhat, PhD, Reviva’s founder, president and chief executive officer, said in a press release.
RP5063, a new chemical entity, is an investigational antipsychotic and potential treatment for PAH, a life-threatening disease caused by increased blood pressure in the lung vasculature. RP-5063 is frequently described as a “dopamine-serotonin system stabilizer” due to its actions on specific dopamine (DA) and serotonin (5-HT) receptors, and its antagonist activity on certain 5-HT receptors. These receptors are increasingly being seen as targets for PAH treatment by scientists.
In a preclinical study in a monocrotaline (MCT)- and a sugen-hypoxia (SuHx)-induced PAH mouse model, RP5063 was found to reduce the mean pulmonary arterial pressure and respiratory resistance, and to normalize blood oxygen levels. The treatment also reduced pulmonary arterial vessels wall thickness and muscular tissue in the PAH mice.
“Based on the mechanism of action, demonstrated preclinical efficacy, and convenient delivery options for enhanced compliance, we believe that RP5063 could become a ‘first in class’ therapy for PAH,” Marc Cantillon, MD, Reviva’s chief medical officer, said. “Having already completed clinical studies phase 1, and phase 2 in patients with schizophrenia and schizoaffective disorders, we look forward to rapidly advancing this drug candidate into a phase 2 study in PAH patients.
“Many PAH patients also suffer from comorbid depression and psychosis which current medications do not address,” Cantillon added, having noted that the drug’s “receptor binding profile” may allow it to treat both PAH and related comorbidities.
Orphan Drug designation applies to drugs and biologics intended to treat, diagnosis or prevent rare diseases or disorders that affect fewer than 200,000 people in the U.S. With this designation, Reviva qualifies for various incentives, such as assistance from the FDA in designing clinical trials, tax credits for clinical trial costs, an exemption from the FDA user fee, and seven years of market exclusivity in the U.S. upon approval of RP5063.
RP5063 is also being developed to treat major depressive disorder, bipolar disorder, attention deficit or hyperactivity disorder, and behavioral disorders in Alzheimer’s and psychosis in Parkinson’s diseases.