Why This Cystic Fibrosis Study Is Getting a Big Boost

Proteostasis Therapeutics Inc. (NASDAQ: PTI) shares jumped on Wednesday after the firm announced positive, initial ex-vivo results of its proprietary cystic fibrosis transmembrane conductance regulator (CFTR) modulators, PTI-801, PTI-808 and PTI-428.

These results specifically apply to individuals with cystic fibrosis (CF) who are ineligible for the current standard of care CFTR modulator therapies due to their genotype.

The data is part of a pan-European strategic initiative, known as HIT-CF (Human Individualized Therapy of CF). This initiative’s goal is to accelerate the development of, and access to, personalized therapies for CF patients, beginning with those for whom no currently approved CFTR modulator therapy is indicated.

HIT-CF collects tissue samples from CF patients and develops organoids, or miniaturized organs, that are genetically identical to the patient donor and share the same micro-anatomy as the organ from which they were derived. So far, rectal organoids from over 300 subjects have been collected for functional profiling and of those, 65 have been tested for response to PTI’s investigational drugs.

Early results support the initiation of enrollment of responding subjects into HIT-CF’s Choices clinical trial, which is designed to evaluate the translation of organoid ex-vivo response to potential clinical benefit.

The results may serve as the basis for a potential Marketing Authorization Application with the European Medicines Agency (EMA) in 2021 through a novel regulatory pathway that is being pursued jointly by Proteostasis and HIT-CF.

Geoffrey Gilmartin, M.D., M.M.Sc., chief medical officer of Proteostasis Therapeutics, commented:

In Europe alone, there are more than 2,300 adult patients whose genotypes render them ineligible for approved CFTR modulators and exclude them from participating in clinical trials with this drug class. This project’s proposed personalized medicine approach is paving a potential new way to develop and provide access to novel CFTR modulators for patients with the most dire need for treatment options that target the cause of the disease. Additionally, based on an individual patient’s disease phenotype and not just the genetic designation, this approach could also create a new path towards more effective treatment for all people with CF.

Shares of Proteostasis were last seen up about 17% at $4.68, in a 52-week range of $0.61 to $5.80. The consensus price target is $7.00.

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