The US FDA has given the go-ahead for MRT5005, Translate Bio’s lead candidate to treat the underlying cause of cystic fibrosis, to be tested in a Phase 1/2 clinical trial.

MRT5005 is designed to address the underlying cause of CF, namely defects in the gene that produces the cystic fibrosis transmembrane conductance regulator (CFTR) protein. MRT5005 is a messenger RNA molecule that contains the blueprint, or instructions, for the proper production of a workng CFTR protein. It is also the first potential mRNA treatment to specifically target the lungs.

The therapy is delivered directly to the lungs in nebulized form, and intended to treat all CF patients regardless of the underlying mutation in their CFTR gene.

The FDA designated MRT5005 an orphan drug in 2015, a move that provides incentives to a company to develop therapeutics for rare diseases, or those affecting less than 200,000 people in the US