PYC Therapeutics (ASX:PYC) started a phase 1b multiple ascending dose study in patients with polycystic kidney disease, with the dosing of the first patient with its drug candidate, PYC-003, completed, according to a Thursday Australian bourse filing.

The study will seek to determine the safety/tolerability profile and optimal repeat dosing regimen of PYC-003 before a proposed transition to a registrational combined phase 2/3 trial.

It will also measure other endpoints, including urinary PC1 protein levels, total kidney volume on magnetic resonance imaging, and the estimated glomerular filtration rate, per the filing.

The company's shares gained nearly 5% in recent Thursday trade.