Abstract: The present invention provides, among other things, methods and compositions for treating primary ciliary dyskinesia (PCD) based on mRNA therapy. The compositions used in treatment of PCD comprise an mRNA comprising a dynein axonemal intermediate chain 1 (DNAI1) coding sequence and are administered at an effective dose and an administration interval such that at least one symptom or feature of PCD is reduced in intensity, severity, or frequency or has a delayed onset. mRNAs with optimized DNAI1 coding sequences are provided that can be administered without the need for modifying the nucleotides of the mRNA to achieve sustained in vivo function.

Abstract: The present invention provides, among other things, improved methods and pharmaceutical compositions for treating cystic fibrosis based on codon optimized mRNA encoding a wild-type Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein.

Abstract: The present disclosure provides a method of pulmonarily administering an oligonucleotide to lung cells. In some embodiments, the disclosure provides formulations that comprise an oligonucleotide that is complementary to a target gene in lung cells and a lipid nanoparticle. Methods of the present disclosure are useful in modifying expression of target genes associated with chronic obstructive pulmonary disease, asthma, and pulmonary fibrosis.

Abstract: The present invention provides, among other things, improved pharmaceutical compositions comprising codon-optimized mRNA encoding a peptide or polypeptide encapsulated in a lipid nanoparticle comprising one or more of the cationic lipids that are particularly effective for pulmonary delivery.