ProQR today announced positive preliminary top-line results from a Phase 1b safety and tolerability clinical trial (Study PQ-010-001; NCT02532764) of QR-010, a novel investigational RNA therapeutic in subjects with cystic fibrosis (CF). Full data from the trial will be presented at the North American CF Conference (NACFC) on November 2-4, 2017.
Study PQ-010-001 was a Phase 1b, randomized, double-blind, placebo-controlled, dose escalation study to evaluate the safety, tolerability and pharmacokinetics of QR-010 in adult subjects with CF homozygous for the F508del mutation. This trial studied 4 dose levels of QR-010 administered via inhalation in 4 single-dose and 4 multiple-dose groups. A number of exploratory efficacy endpoints were assessed in the multiple dose groups: respiratory symptoms (as measured by a validated patient-reported outcome tool, the Cystic Fibrosis Questionnaire-Revised Respiratory Symptom Score, or CFQ-R RSS), lung function (as measured by mean absolute change in percent predicted forced expiratory volume in 1 second, or ppFEV1), sweat chloride test and weight change. This study included subjects with, on average, a normal lung function at baseline (mean ppFEV1 86%, range 69-116%). As therapeutic trials typically study subjects with normal-to-severe lung function at baseline (ppFEV1 <90%), a subgroup was pre-defined to analyze the exploratory efficacy endpoints in this population. The trial recruited 70 participants and was conducted at 23 sites in 10 countries in Europe and North America.
J. Stuart Elborn, the principal investigator of the study, Clinical Chair in Respiratory Medicine at Imperial College, Consultant at Royal Brompton Hospital, and immediate past-president of the European Cystic Fibrosis Society, added, “QR-010 exceeded expectations in this study as an innovative investigational therapy for the treatment of cystic fibrosis for which the need remains high. The improvements demonstrated in reduction of respiratory symptoms are very encouraging and intriguing and of course of enormous importance to people with CF. The results of this study together with the previous proof of concept study are strongly supportive of the further development of QR-010.”
In this trial QR-010 was observed to be safe and well-tolerated across all doses, with an overall safety profile similar to placebo. There were no serious adverse events related to treatment. After inhaled administration in some dose groups, QR-010 was detected in the blood. Subjects who received QR-010 in the 6.25, 12.5 and 25 mg multiple dose groups reported fewer respiratory symptoms after 4 weeks of treatment as measured by the increased CFQ-R RSS, with mean improvements of 13.0, 19.2 and 14.3 points, respectively, compared to placebo. The effect was more pronounced in the pre-defined subgroup of subjects with a lower lung function at the start of the study (baseline ppFEV1 70-90%) with a mean increase of up to 27.5 points compared to placebo. These improvements exceeded the minimal clinically important difference (MCID) of 4.0 points. A supportive trend of improved lung function was observed in the same multiple dose groups, as measured by mean absolute change in ppFEV1 compared to placebo. The trend was stronger in the subgroup of subjects with a lower lung function at baseline. The table below summarizes the data per multiple dose group. As expected, no effect was observed on sweat chloride and weight.
The Phase 1b study achieved its goals for evaluation of QR-010 including demonstrating safety and tolerability across a range of doses, identified a dosing window, exhibited uptake of the RNA oligonucleotide into circulation following inhalation, and demonstrated early signals of clinical efficacy.
“The positive results in the first two clinical trials of QR-010 significantly increase the confidence that QR-010 has the potential to become an effective treatment of CF. The improvement in CFQ-R RSS with the supportive FEV1 data as shown in this Phase 1b trial is very exciting,” said Noreen R. Henig, M.D, Chief Medical Officer at ProQR. “I want to thank the entire CF community including those living with CF, clinical investigators, scientists, the CF Foundation, the European CF Society and the US and European therapeutic development networks for their unwavering commitment.”
Partnership with Cystic Fibrosis Foundation Therapeutics (CFFT)
ProQR and CFFT entered into a partnership in 2014 to develop QR-010 for people with CF due to the F508del mutation. The initial partnership included support for the Phase 1b trial as well as the NPD proof of concept study that reported positive results in 2016. Based on the results of the clinical trials of QR-010, ProQR and CFFT intend to expand the partnership to explore the inhaled oligonucleotide platform for stop-codon mutations (also called “Class I” mutations) in CFTR. Stop-codon mutations cannot be targeted with small molecule potentiator or corrector molecules, and therefore have a high unmet medical need. ProQR intends to target these mutations using its proprietary Axiomer® technology, which has shown compelling data in non-clinical studies, to repair the stop-codon mutations in the RNA, leading to removal of the premature stop-codon. Approximately 12,000 patients, accounting for 15% of CF patients in the western world, have a stop-codon mutation leading to a severe form of CF.
”The results of this Phase 1b trial support QR-010’s potential to be a meaningful therapy for people with cystic fibrosis,” said Daniel A. de Boer, Chief Executive Officer at ProQR. ”With these results in hand we are designing a path forward for the development of QR-010, either independently or with a potential partner. Furthermore we are looking forward to expanding our partnership with the CFFT to explore the inhaled oligonucleotide platform also for people that have CF due to stop-codon mutations.”