Proteostasis Therapeutics, Inc. Presents New Data Demonstrating Potential for Genotype-Agnostic and Combination Therapies for People with Cystic Fibrosis

Proteostasis Therapeutics, Inc. (NASDAQ: PTI), a biopharmaceutical company developing small molecule therapeutics to treat diseases caused by dysfunctional protein processing.


such as cystic fibrosis (CF), today announced new preclinical data on the company’s first-in-class genotype-agnostic amplifier and novel corrector at the 13th Annual European Cystic Fibrosis Society (ECFS) Basic Science Conference near Pisa, Italy from March 30-April 2. The company will hold a conference call and webcast today at 4:00 p.m. ET to discuss the data being presented at the conference and the company’s outlook for 2016.

We are strongly encouraged by our early findings and the potential implications for improving the lives of people with cystic fibrosis,” said Meenu Chhabra, President and Chief Executive Officer of Proteostasis Therapeutics. “Patients treated with currently available therapies still struggle to achieve full lung function, while many are not receiving treatment at all due to rare mutations of the disease. The results from our preclinical studies show the potential of our CFTR amplifier to restore lung function to near-normal levels not only in patients with the most common gene mutation found in cystic fibrosis, but across multiple gene mutations.”

In the company’s poster presentation, “Characterization of CFTR amplifiers, mutation-agnostic modulators that increase protein levels and complement other CF therapeutic modalities,” company researchers describe a new class of modulator – an amplifier – which increases the levels of immature CFTR protein available for other modulators, such as correctors and potentiators, to act upon.

  • The study found that amplifiers

  • increase CFTR immature protein and stabilize CFTR mRNA;

  • increase substrate for additional modulators;

  • work across CFTR genotypes; and,

  • demonstrate activity in non-lung tissues and in vivo.

The early findings suggest the potential for the novel class of amplifiers to enhance CFTR translation efficiency across CFTR mutations and be used in combinations to boost the activity of additional modulators in treating CF.

In a second poster presentation, company scientists have identified a novel corrector with properties that differentiate it from clinical-stage correctors such as lumacaftor or VX-661. The study, “A novel corrector for F508del-CFTR that complements existing CFTR modulators in vitro,” demonstrated that exposure to Proteostasis Therapeutics’ corrector significantly increases the proportion of mature CFTR protein. Moreover, in vitro CFTR function is increased accordingly when the company’s corrector is dosed with other modulators, including lumacaftor, potentiators and its amplifier.

“We believe we have the potential to dramatically improve therapeutic outcomes for patients with cystic fibrosis,” said Po-Shun Lee, M.D., Executive Vice President and Chief Medical Officer of Proteostasis Therapeutics. “The data not only validate the use of our novel CFTR amplifiers in combination with existing therapies such as Orkambi and Kalydeco, but they also represent an important early milestone in developing a new and possibly game-changing triple combination therapy for those living with the disease.”

Following is a schedule of the company’s poster presentations and conference call:

Poster Presentations

Thursday, March 31

Time: 2:30-3:30 p.m. CEST

Title: Characterization of CFTR amplifiers, mutation-agnostic modulators that increase protein levels and complement other CF therapeutic modalities

Friday, April 1

Time: 6:30-7:30 p.m. CEST

Title: A novel corrector for F508del-CFTR that complements existing CFTR modulators in vitro

Conference Call and Webcast

Wednesday, March 30

Time: 4:00 p.m. ET

The conference call can be accessed by dialing 1-877-626-4740 (toll-free domestic) or 1-281-973-6278 (international) and referring to conference ID 78792593. A live webcast and accompanying slide presentation will be available on the Event Calendar page in the Investors & Media section of the company’s website, A replay of the webcast will be available on the company’s website shortly after the conclusion of the conference call.

About Cystic Fibrosis

Cystic fibrosis (CF) is a life threatening, progressive genetic disease affecting an estimated 70,000-100,000 people worldwide. The disease is caused by defects in the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which acts as a passageway to promote the transport of salt and water to tissues such as the lungs, skin and pancreas. The defect disrupts healthy ion flow and causes a buildup of thick mucus and bacteria in several organs, resulting in persistent lung infections and the inability for the body to break down food and absorb vital nutrients. While advancements in research and treatments have extended the life expectancy for those living with the disease, CF remains a serious, life-limiting condition with no known cure.

About Proteostasis Therapeutics

Proteostasis Therapeutics, Inc. is a biopharmaceutical company dedicated to the discovery of groundbreaking therapies to treat diseases caused by dysfunctional protein processing, such as cystic fibrosis (CF). Headquartered in Cambridge, MA, the Proteostasis Therapeutics team focuses on the proteostasis network and identifying therapies that modulate the proteostasis imbalance in cells and restore protein function. The company is currently enrolling eligible adults with CF to participate in its Phase 1 clinical trial of PTI-428, a unique modulator called an amplifier, that when used in combination with existing treatments and therapies has shown a consistent positive effect on CFTR protein activity in pre-clinical studies. In addition to its multiple programs in CF, the company has formed collaborations with Biogen to research and identify therapeutic candidates for neurodegenerative disease and with Astellas Pharma, Inc. to research and identify therapies targeting the Unfolded Protein Response (UPR) pathway. For more information visit

Forward-Looking Statements

This release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, including statements regarding the advancement of, and anticipated development plans related to, the Company’s product candidates and preclinical and clinical studies. Any forward-looking statements are based on management’s current expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in or implied by such forward-looking statements. These risks and uncertainties include, but are not limited to, the risk of cessation or delay of any of the ongoing or planned clinical studies or development activities for our product candidates, the risk of a delay in the enrollment of patients in the Company’s clinical studies, the risk that the results of previously conducted studies involving similar product candidates will not be repeated or observed in ongoing or future studies involving current product candidates, and the risk that any one or more of our product candidates will not be successfully developed and commercialized. For a discussion of other risks and uncertainties, and other important factors, any of which could cause our actual results to differ from those contained in the forward-looking statements, see the section entitled “Risk Factors” in our registration statement on Form S-1 that we filed in connection with our initial public offering, as well as discussions of potential risks, uncertainties, and other important factors in our subsequent filings with the Securities and Exchange Commission. All information in this press release is as of the date of the release, and Proteostasis Therapeutics undertakes no duty to update this information unless required by law.

Availability of other information about Proteostasis Therapeutics, Inc.

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