ReCode Therapeutics has dosed the first subject in a Phase I clinical trial of its inhaled messenger ribonucleic acid (mRNA)-based therapy, RCT1100, for primary ciliary dyskinesia (PCD) caused by dynein axonemal intermediate chain 1 (DNAI1) gene mutations.

The company’s Selective Organ Targeting (SORT) lipid nanoparticle (LNP) delivery platform was instrumental in developing the therapy, which aims to restore ciliary function by delivering DNAI1 mRNA to affected cells.

DNAI1 mRNA demonstrated promising results, successfully producing the DNAI1 protein and improving ciliary function in a PCD model in preclinical studies.

Following the successful completion of Part A of the Phase I trial in August last year, which showed no serious side effects in 40 healthy volunteers, Part B will now focus on the safety and tolerability of RCT1100 in PCD patients with DNAI1 gene mutations.

The Part B open-label portion will assess a single ascending dose of inhaled RCT1100 given using a nebuliser in PCD patients.

It will have up to nine subjects, with recruitment taking place across various sites in the US and across the globe.

ReCode Therapeutics CEO Shehnaaz Suliman said: “This is the first time a patient with PCD has received a targeted mRNA-based therapeutic.

“This study will evaluate RCT1100 as a potential novel treatment option for patients who do not have any approved therapies.

“We are especially grateful to the PCD community for the continued support and collaboration as we continue our efforts to develop a treatment for PCD patients.”

Apart from RCT1100, the company’s lead programme includes RCT2100 to treat cystic fibrosis patients with Class I mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene and unresponsive to presently approved CFTR modulators.

Both RCT1100 and RCT2100 are inhaled disease-modifying mRNA-based therapies designed leveraging the SORT LNP delivery platform.

ReCode Therapeutics president and chief scientific officer David Lockhart said: “With no approved therapeutics to treat the underlying cause of PCD, we are excited to bring our inhaled mRNA-based therapy forward into the clinic and to patients.

“RCT1100 is currently the only treatment in clinical development for PCD. This study brings us one step closer to improving the respiratory health and quality of life of people living with this disease.”