Healthcare Business

Why Proteostasis Shares Are Exploding

Chris Lange

Proteostasis Therapeutics Inc. (NASDAQ: PTI) shares absolutely exploded in Tuesday’s session, more than doubling after the firm reported positive results from its cystic fibrosis (CF) study. These positive study results spread across all three of the company’s CF pipeline programs.

Ultimately, these results support the goal of studying the company’s novel cystic fibrosis transmembrane conductance regulator (CFTR) modulators in doublet and triplet combinations in CF subjects.

As part of this, Proteostasis announced that it has completed its Phase 2 study designed to evaluate the efficacy, safety and tolerability of PTI-428 over a 28-day treatment of CF patients on background Orkambi (lumacaftor/ivacaftor). The addition of PTI-428 to Orkambi demonstrated mean absolute improvements compared to the placebo. This treatment effect was achieved by day 14 and sustained through 28 days of dosing

Separately, the company shared initial data from the first five subjects (four PTI-801 treated and one placebo) of the first dose level tested in the 14-day dosing study of PTI-801 in CF patients on background Orkambi therapy. These initial data also showed no clinically meaningful drug-drug interactions with either lumacaftor or ivacaftor. There were no serious adverse safety events reported that were considered as possibly drug related.

Meenu Chhabra, president and CEO, added about PTI-801:

This initial data begins to validate the in vitro profile of PTI-801 and its potential to bolster efficacy for subjects on Orkambi. We are eager to explore a dose response in the next planned cohort with 200 mg of once a day dosing.

Also a total of 48 healthy volunteers have participated and completed the study of PTI-808, a novel CFTR potentiator that was tested in single and multiple dose cohorts. PTI-808 was found to be generally well tolerated.

Chhabra, concluded:

The phase 2 data with PTI-428, along with initial clinical evidence with PTI-801 and the completion of co-administration safety and PK studies with all three CFTR modulators in healthy volunteers further cements our progress towards combination development with our proprietary compounds in the CF patient population. We look forward to initiating a doublet study of PTI-801 and PTI-808 in CF subjects and progressing towards a triple combination study in CF subjects in 2018.

Shares of Proteostasis were last seen up over 190% at $6.84, with a consensus analyst price target of $11.33 and a 52-week range of $1.41 to $16.67.