Reviva-FDA Meeting Paves Way for Phase 2 Clinical Trial of RP5063 as a PAH Therapy

Reviva Pharmaceuticals has had a meeting with the U.S. Food and Drug Administration that paves the way for a Phase 2 clinical trial of its neurodegenerative therapy RP5063 in pulmonary arterial hypertension.

The meeting dealt with an investigational new drug application the company will submit on RP5063. What is known in therapy development circles as a pre-IND meeting is aimed at facilitating communication about an IND application between a therapy developer and the FDA.

At the meeting, the FDA accepted RP5063 pharmacology, safety and toxicology data from studies it has conducted so far on RP5063, Reviva said. The agency also provided guidance on obtaining a disease-modifying designation for the therapy and advancing it into a Phase 2 trial. The FDA must approve an IND application before a drug can be tested in trials.

RP5063 has been tested in trials as a treatment for schizophrenia, but not for PAH.

“We are very pleased with the outcome of the pre-IND meeting with FDA,” Dr. Laxminarayan Bhat,  the president and chief executive officer of Reviva, said in a press release. “We look forward to advancing RP5063 into a Phase 2 clinical trial for PAH in early 2018.”

RP5063 is both an anti-psychotic therapy candidate as well as a potential treatment for PAH. Reviva describes it as a dopamine-serotonin system stabilizer.

Serotonin is a neurotransmitter that plays a key role in the correct functioning of the human brain, lungs and heart. Faulty serotonin signaling is thought to be involved in the development and progression of PAH.

Characteristics of PAH include high blood pressure in the arteries that carry blood from the heart to the lungs; narrowing of the arteries, which makes it difficult to pump blood through them; and less oxygen in blood flowing from the lungs to other parts of the body.

Preclinical-trial studies have shown that RP5063 decreased pulmonary artery pressure, lowered lung blood vessel resistance, and stabilized blood oxygen levels in animal models of PAH. It also significantly reduced the thickness of pulmonary artery vessel walls and muscles, which had contributed to resistance.

Reviva presented the findings of the studies at the American Thoracic Society International Conference in 2016 and published them.

Based on positive results from a recently completed Phase 2 clinical trial of RP5063 as a treatment for schizophrenia and schizoaffective disorders, it could become the first treatment for both PAH and the most common psychiatric symptoms associated with it.

The FDA granted RP5063 orphan drug status as a treatment for PAH in November 2016.

Reviva has put plans in place for a pivotal Phase 3 trial of RP5063 as a treatment and maintenance therapy for schizophrenia. Because it can regulate both dopamine and serotonin receptors, it has the potential to treat other neuropsychiatric diseases, including Alzheimer’s, Parkinson’s, and attention deficit hyperactivity disorder, or ADHD.