FDA Agrees to Fast Track Potential Cystic Fibrosis Therapy, QR-010, Now Under Clinical Testing

ProQR Therapeutics announced that QR-010, an inhaled therapy it is developing to treat cystic fibrosis patients with the ∆F508 mutation in the CFTR gene (the gene that is defective in CF), has received Fast Track designation from the U.S. Food and Drug Administration (FDA) to speed its testing and review. The drug is now being evaluated in two clinical trials in CF patients with this common mutation.

QR-010 is an inhaled therapy administered through a nebulizer that, unlike other CF drugs currently on the market, is designed to repair the genetic defect at the RNA level in order to restore the function of the CFTR protein. Restoring CFTR function can potentially stop disease progression.

“We are very pleased with the Fast Track designation the FDA granted us for QR-010. It highlights the unmet medical need in cystic fibrosis and the need for innovative and more efficacious medicines for CF. We look forward to working with the FDA to bring QR-010 to patients faster,” Daniel de Boer, chief executive officer of ProQR, said in a recent press release. “We are also looking forward to releasing data for the first-in-human trials of QR-010 in CF patients later this year during the North American CF conference (NACFC), held on 27–29 October 2016 in Orlando, Florida.”

ProQR is conducting two studies of QR-010 in CF patients. The first trial (PQ-010-002 / NCT02564354) is an open label, 28-day proof-of-concept study assessing the effect of QR-010 on the nasal potential difference (NPD), a central measurement of CFTR function. This trial is evaluating 16 patients with CF, with the option to enroll 16 additional patients. Of the initial 16 patients currently enrolled, eight carry two copies of the ΔF508 mutation and the other eight carry one copy of this mutation plus one other disease causing mutation. The company expects to present top-line results from the first 16 patients at NACFC.

The second trial (PQ-010-001 / NCT02532764) is an international, randomized, double-blind, placebo-controlled, Phase 1b safety and tolerability, dose-escalation 28-day study of QR-010 in 64 CF patients carrying two copies of the ΔF508 CFTR gene mutation. Additionally, exploratory efficacy endpoints include lung function, weight gain, sweat chloride, and CFQ-R Respiratory Symptom Score.

ProQR anticipates to present preliminary data from the single and multiple ascending dose cohorts at the same time as the outcomes for the proof-of-concept trial.

CF is a genetic disease affecting more than 70,000 patients worldwide. CF patients have viscous mucus accumulating in their vital organs, and such mucus can clog tubes and organs to disrupt processes in the body. The ΔF508 is the most common mutation in CF, affecting more than 70 percent of all CF patients.