23 August 2021

PureTech Presents Phase 1 Data for LYT-100 at the European Respiratory Society International Congress 2021

LYT-100 was well-tolerated when given twice-daily over multiple ascending doses with no maximum tolerated dose observed

Results demonstrated dose-proportional PK profile and a modest food effect

LYT-100 is currently being evaluated in two Phase 2 trials in patients with Long COVID respiratory complications or breast cancer-related, upper limb secondary lymphedema, and planning is underway to potentially evaluate LYT-100 in IPF

PureTech Health plc (Nasdaq: PRTC, LSE: PRTC) ("PureTech" or the "Company"), a clinical-stage biotherapeutics company dedicated to discovering, developing and commercializing highly differentiated medicines for devastating diseases, today announced the presentation of the Phase 1 multiple ascending dose and food effect study of LYT-100 at the virtual European Respiratory Society International Congress. LYT-100 is the lead therapeutic candidate from within PureTech's Wholly Owned Pipeline, and it is being advanced for the potential treatment of conditions involving inflammation and fibrosis and disorders of lymphatic flow.

"These data further support the favorable tolerability profile of LYT-100 and have helped inform both our ongoing Phase 2 trials as well as potential future trials in additional indications, including idiopathic pulmonary fibrosis," said Michael Chen, PhD, Head of Innovation at PureTech. "LYT-100 is a deuterated form of pirfenidone, which retains the beneficial pharmacology of pirfenidone and also appears to have a favorable tolerability profile based on the preclinical and clinical data generated thus far. We believe this molecule has the potential to overcome the GI adverse events associated with the current standards of care and become the frontline treatment for patients with interstitial lung disease."

Multiple ascending dose and food effect study results

The Phase 1 multiple ascending dose food and effect study was a randomized, double-blind, placebo-controlled study of LYT-100 in healthy volunteers in both fed and fasting states. Plasma concentrations of LYT-100 and its metabolites were measured to determine pharmacokinetic (PK) parameters.

Topline results from the Phase 1 study were first announced in November 2020. The expanded analysis details the safety, tolerability and favorable PK profile of LYT-100 at doses from 100mg to 1000mg in both fed and fasting healthy volunteers and supports the potential for twice-daily dosing in future studies.

A dose-proportional PK profile was observed with LYT-100 throughout the range of doses studied. In the single ascending food effect cohort, exposure was slightly lower in the fed condition. The ratios of exposure during fed conditions were approximately 20% to 25% less than exposure during fasting.

Given that the maximum tolerated dose for LYT-100 was not determined in this study, PureTech initiated a second multiple ascending dose study earlier this year to evaluate higher doses of the drug in healthy volunteers.

About LYT-100

LYT-100 is PureTech's most advanced therapeutic candidate from within its Wholly Owned Pipeline. A deuterated form of pirfenidone, an approved anti-inflammatory and anti-fibrotic drug, LYT-100 is being advanced for the potential treatment of conditions involving inflammation and fibrosis, including lung disease (e.g., IPF and potentially other PF-ILDs and Long COVID respiratory complications and related sequelae), and disorders of lymphatic flow, such as lymphedema. PureTech completed a Phase 1 multiple ascending dose and food effect study evaluating LYT-100 in healthy volunteers and found it to be well-tolerated at all doses tested. In the fourth quarter of 2020, PureTech initiated a Phase 2 trial evaluating LYT-100 as a potential treatment for Long COVID respiratory complications and related sequalae and a Phase 2a proof-of-concept study evaluating LYT-100 in patients with breast cancer-related, upper limb secondary lymphedema. PureTech has also initiated three additional Phase 1 clinical trials to explore further the PK, dosing and tolerability of LYT-100 in healthy volunteers. Results from these trials are anticipated in the fourth quarter of 2021 and are expected to provide additional supportive data that may inform the clinical development of LYT-100 across indications, including IPF and other PF-ILDs.

About PureTech Health

PureTech is a clinical-stage biotherapeutics company dedicated to discovering, developing and commercializing highly differentiated medicines for devastating diseases, including inflammatory, fibrotic and immunological conditions, intractable cancers, lymphatic and gastrointestinal diseases and neurological and neuropsychological disorders, among others. The Company has created a broad and deep pipeline through the expertise of its experienced research and development team and its extensive network of scientists, clinicians and industry leaders. This pipeline, which is being advanced both internally and through PureTech's Founded Entities, is comprised of 26 therapeutics and therapeutic candidates, including two that have received FDA clearance and European marketing authorization, as of the date of PureTech's most recently filed Annual Report on Form 20-F. All of the underlying programs and platforms that resulted in this pipeline of therapeutic candidates were initially identified or discovered and then advanced by the PureTech team through key validation points based on the Company's unique insights into the biology of the brain, immune and gut, or BIG, systems and the interface between those systems, referred to as the BIG Axis.

For more information, visit www.puretechhealth.com or connect with us on Twitter @puretechh.

Cautionary Note Regarding Forward-Looking Statements

This press release contains statements that are or may be forward-looking statements, including statements that relate to our product candidates and approach towards addressing major diseases, future prospects, developments, and strategies. The forward-looking statements are based on current expectations and are subject to known and unknown risks and uncertainties that could cause actual results, performance and achievements to differ materially from current expectations, including, but not limited to, our expectations regarding the potential therapeutic benefit of LYT-100 in patients with conditions involving inflammation and fibrosis and disorders of lymphatic flow, expectations regarding data from our current Phase 1 and 2 trials of LYT-200 and their potential to provide supportive data for further development and those risks and uncertainties described in the risk factors included in the regulatory filings for PureTech Health plc. These forward-looking statements are based on assumptions regarding the present and future business strategies of the company and the environment in which it will operate in the future. Each forward-looking statement speaks only as at the date of this press release. Except as required by law and regulatory requirements, neither the company nor any other party intends to update or revise these forward-looking statements, whether as a result of new information, future events or otherwise.