On December 11, 2019, the Company issued the press release attached hereto as Exhibit 99.1 announcing the following information:
Proteostasis Therapeutics, Inc. (NASDAQ:PTI), a clinical stage biopharmaceutical company dedicated to the discovery and development of groundbreaking
therapies to treat cystic fibrosis (CF), today announced positive, initial ex-vivo results of PTI’s proprietary cystic fibrosis transmembrane conductance regulator (CFTR) modulators, PTI-801, PTI-808, and PTI-428, in individuals with CF who are ineligible for the current standard of care CFTR modulator therapies due
to their genotype. The data are part of a pan-European strategic initiative, known as HIT-CF (Human Individualized Therapy of CF), which seeks 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 is sponsored by the European Commission Horizon 2020 program, in which
CF-Europe, a patient organization representing more than 48,000 individuals with CF, collaborates and with the European Cystic Fibrosis Society Clinical Trial Network
(ECFS-CTN), which is recruiting adult CF patients into the ex-vivo study through its 43 clinical trial centers. 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.
As of today, 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 clinical trial known as “CHOICES” (Crossover trial based on Human
Organoid Individual response in CF - Efficacy Study), which is designed to evaluate the translation of organoid ex-vivo response to potential clinical benefit, such as
changes in FEV1 and sweat chloride. CHOICES, which is expected to initiate in mid-2020, will be the first ever personalized medicine-based study in CF,
with initial data expected by the end of 2020. Fully funded by the HIT-CF, this trial is a placebo controlled, double blind, crossover study with an 8-week treatment
period and 6 months of uninterrupted dosing. 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 which is being pursued jointly by
Proteostasis and HIT-CF. The CHOICES clinical study is part of PTI’s broader clinical development strategy for its CFTR modulator candidates that is already separately funded for the common genotypes.
Results from the HIT-CF project to date will be presented at the Keystone Symposia on Tissue Organoids titled
“Tissue Organoids as Models of Host Physiology and Pathophysiology of Disease (J1)” taking place on January 19-23, 2020 in Vancouver, BC, Canada.
Safe Harbor
To the extent that statements in this
release are not historical facts, they are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Words such as
“aim,” “may,” “will,” “expect,” “anticipate,” “estimate,” “intend,” and similar expressions (as well as other words or expressions referencing future events, conditions or
circumstances) are intended to identify forward-looking statements. Examples of forward-looking statements made in this release include, without limitation, statements regarding the expected presentation at an upcoming conference. Forward-looking
statements made in this release involve substantial risks and uncertainties that could cause actual results to differ materially from those expressed or implied by the forward-looking statements, and we, therefore cannot assure you that our plans,
intentions, expectations or strategies will be attained or achieved. Such risks and uncertainties include, without limitation, our expectations regarding our participation in HIT-CF’s pan-European strategic initiative, the potential of our proprietary combination therapies for the treatment of CF, the potential benefit of our proprietary combination therapies to patients, expected timing of
patient enrollment in, data from, the completion of, and reporting top line results of our clinical studies and cohorts for our clinical programs, including our planned Phase 2 program and initiation of a pivotal or registrational study, the
possibility final or future results from our drug candidate trials (including, without limitation, longer duration studies) do not achieve positive results or are materially and negatively different from or not indicative of the preliminary results
reported by the Company (noting that these results are based on a small number of patients and small data set), uncertainties inherent in the execution and completion of clinical trials (including, without limitation, the possibility that FDA or
other regulatory agency comments delay, change or do not permit trial commencement, or intended label, or the FDA or other regulatory agency requires us to run cohorts sequentially or conduct additional cohorts or
pre-clinical or clinical studies), in the enrollment of CF patients in our clinical trials in a competitive clinical environment, in the timing of availability of trial data, in the results of the clinical
trials, in possible adverse events from our trials, in the actions of regulatory agencies, in the endorsement, if any, by therapeutic development arms of CF patient advocacy groups (and the maintenance thereof), in the commercialization and
acceptance of new therapies, and those set forth in our Annual Report on Form 10-K for the year ended December 31, 2018, our Quarterly Report on Form 10-Q for the
quarter ended September 30, 2019 and our other SEC filings. We assume no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.
The above information is not an admission as to the materiality of any information therein. The Company undertakes no duty or obligation to update or revise
the information contained in this report, although it may do so from time to time as its management believes is appropriate. Any such updating may be made through the filing of other reports or documents with the SEC, through press releases or
through other public disclosures.