Just the other day, Vertex announced that it had to implement a temporary pause for the evaluation of VX-522 for the treatment of patients with cystic fibrosis (CF). This particular therapy was a nebulized version of CFTR mRNA therapy in order to allow these patients to generate functional CFTR proteins necessary to reduce disease.
A particular problem with cystic fibrosis is that there is a mutation of the CFTR gene, which encodes CFTR proteins necessary to regulate salt and water moving in and out of cells in the lungs. Without proper proteins, patients are unable to clear substances from the lungs. In essence, there is buildup of sticky mucus that causes a host of issues for them.
The temporary pause came about for the ongoing multiple ascending dose (MAD) portion of the phase 1/2 study using VX-522 to treat these CF patients. Not much has been said about the pause other than the fact that there is a need to look into a tolerability issue that came about. If any positive is to be gleaned from this note by Vertex, it is that at least the trial wasn’t outright discontinued due to a major serious adverse event (SAE).
Hopefully, the study can get back on track, but the temporary pause for now is not ideal. Vertex already has several drugs approved to treat CF patients with a specific mutation type. The goal of VX-522 as an inhaled messenger RNA (mRNA) therapy was to go after approximately 5,000 patients who don’t benefit from currently approved CFTR modulators.
Basically, this therapy was being developed to treat CF patients regardless of mutation type. The company didn’t develop this candidate itself because it actually tapped a collaboration agreement with Moderna back in 2016 to develop such efforts. However, in 2020, both companies entered into a second collaboration agreement in order to develop lipid nanoparticles (LNPs) and mRNAs to deliver functioning CFTR proteins into the lungs.
Moderna received $75 million because of this deal and would also be eligible to earn development, regulatory, and commercial milestone payments as well. Plus, royalties for net product revenues generated from any products to be sold. Even if the pause is ultimately lifted, VX-522 as an inhaled mRNA therapy isn’t the only game in town. There is the expected release of data using inhaled mRNA therapies to treat CF patients from both Arcturus Therapeutics and ReCode Therapeutics during this quarter.
