ProQR concludes QR-010 dosing in Phase Ib trial to treat cystic fibrosis

The Netherlands-based ProQR Therapeutics has concluded dosing patients in a Phase Ib clinical trial of QR-010 for the treatment of patients with cystic fibrosis.

QR-010 is a RNA-based oligonucleotide being developed to target mRNA in patients having the F508del mutation, which is a deletion of three coding base pairs in the CFTR gene.

Designed for self-administration through a handheld aerosol delivery device called eFlow Nebuliser, QR-010 is intended to bind to the defective CFTR mRNA for restoring CFTR function.

The randomised, double-blind, placebo-controlled Phase Ib trial evaluated the safety, tolerability and pharmacokinetics of 6.25mg, 12.5mg, 25mg and 50mg dose levels of QR-010 in solution per dose given through inhalation.

Conducted at 26 centres in Europe and North America, the trial included adults with mild disease and a baseline predicted FEV1 value of greater than 70%.

"QR-010 has the potential to be an innovative RNA therapy for patients with CF due to the F508del mutation."

ProQR Therapeutics chief medical officer Noreen Henig said: “QR-010 has the potential to be an innovative RNA therapy for patients with CF due to the F508del mutation. 

“Completion of the Phase Ib study is an important step in development, and builds upon the pre-clinical data and positive PQ-010-002 study where QR-010 demonstrated a direct effect on restoring CFTR function.”

The 28-day trial included a total of 64 patients in eight cohorts, one to four of which were given a single dose of QR-010, while five to eight were administered with 12 doses.

Exploratory efficacy endpoints such as sweat chloride, weight gain and change in FEV1 are currently being evaluated, with plans to report the trial’s top-line results in the last week of next month.