US-based PhaseBio Pharmaceuticals has started dosing pulmonary arterial hypertension (PAH) patients in an open-label study to assess its investigational candidate PB1046.
Developed as a once-weekly formulation, PB1046 is an agonist of vasoactive intestinal peptide (VIP) receptor designed to target VPAC receptors in the pulmonary, cardiovascular and immune systems.
PB1046 contains a VIP analogue fused with the firm’s elastin-like polypeptide (ELP) biopolymer.
The open-label, single cohort, exploratory study will evaluate the tolerability, safety and hemodynamic response of individually dose-titrated PB1046 administered to adult PAH subjects having a permanently implanted hemodynamic monitor, CardioMEMS HF System.
Additionally, the study will monitor pharmacokinetics, exercise capacity via the six-minute walk distance test, along with exploratory biomarkers.
PhaseBio chief medical officer John Lee said: “Previous studies have demonstrated that reduced VIP levels may be a critical factor in PAH disease development and progression.
“Consequently, VIP-based therapies such as PB1046 have the potential to provide benefit to patients who currently lack adequate treatment options.”
Data obtained from the open-label study is expected to support a placebo-controlled Phase II trial scheduled to commence early next year.
In a previous Phase I trial, PB1046 is reported to have demonstrated favourable tolerability and a prolonged dose-dependent effect on blood pressure of essential hypertension patients.
The drug candidate had obtained orphan drug designation from the US Food and Drug Administration (FDA) for the treatment of PAH and cardiomyopathy caused due to dystrophinopathies.
Currently, PB1046 is being further studied in a Phase IIa ascending dose trial for treating heart failure patients.