Stealth BioTherapeutics Announces New SBT-272 Data and Trial Initiation

BOSTONMarch 30, 2022 /PRNewswire/ — Stealth BioTherapeutics Corp (Nasdaq: MITO), a clinical-stage biotechnology company focused on the discovery, development, and commercialization of novel therapies for diseases involving mitochondrial dysfunction, announced today the presentation of new SBT-272 preclinical data at the Mitochondrial Biochemistry in Health and Disease Symposium in Breckenridge, CO and dosing of the first subject in its Phase 1 clinical trial of SBT-272.

The new data demonstrated behavioral and metabolic improvements with SBT-272 in a mouse model of Huntington’s disease.  In the study, mice were treated for up to 8 weeks with daily SBT-272 and displayed significantly improved motor function compared to vehicle-treated mice. SBT-272-treated mice also showed improved metabolism in multiple brain regions of the diseased animals, assessed in vivo using PET imaging.

The Phase 1 clinical trial is a double-blind, placebo controlled safety study enrolling up to 64 healthy subjects across multiple cohorts. SBT-272 is being administered via subcutaneous injection. As a primary objective, the study will evaluate safety and tolerability of single and multiple ascending doses of SBT-272. Secondary objectives include an analysis of the pharmacokinetic profile of SBT-272 and identification of the appropriate dose range for Phase 2 testing.

“We see tremendous potential for SBT-272 across a spectrum of neurodegenerative diseases of mitochondrial dysfunction, with supportive preclinical data in amyotrophic lateral sclerosis, frontotemporal lobar dementia, Parkinson’s and, with our new data, Huntington’s disease,” said Chief Executive Officer Reenie McCarthy. “It’s exciting to progress this promising compound into the clinic as an important first clinical step toward initiating planned development efforts for patients affected by these devastating diseases.”

About SBT-272

SBT-272 is a novel peptidomimetic which has been shown to have mitochondria-protective and neuroprotective effects across nonclinical models of amyotrophic lateral sclerosis (ALS), frontotemporal lobar dementia, alpha-synucleinopathy, a rare form of dementia that is similar to Parkinson’s disease, Huntington’s disease and ischemic stroke.  We have also observed SBT-272-mediated improvements in functional assessments, lifespan, inflammation, and reduction of protein aggregates across certain of these nonclinical models.  We are studying subcutaneous SBT-272 in a Phase 1 clinical trial in healthy human volunteers.  We plan to initiate chronic toxicology studies during 2022.  We hope to develop SBT-272 for ALS and other neurological diseases of mitochondrial dysfunction.

About Stealth

We are a clinical-stage biotechnology company focused on the discovery, development, and commercialization of novel therapies for diseases involving mitochondrial dysfunction. Mitochondria, found in nearly every cell in the body, are the body’s main source of energy production and are critical for normal organ function. Dysfunctional mitochondria characterize a number of rare genetic diseases and are involved in many common age-related diseases, typically involving organ systems with high energy demands such as the eye, the neuromuscular system, the heart and the brain. We believe our lead product candidate, elamipretide, has the potential to treat ophthalmic diseases entailing mitochondrial dysfunction, such as dry AMD, rare neuromuscular disorders, such as primary mitochondrial myopathy and Duchenne muscular dystrophy, and rare cardiomyopathies, such as Barth syndrome. We are evaluating our second-generation clinical-stage candidate, SBT-272, for rare neurological disease indications, such as amyotrophic lateral sclerosis and frontotemporal lobar dementia, following promising preclinical data. We have optimized our discovery platform to identify novel mitochondria-targeted compounds which may be nominated as therapeutic product candidates or utilized as mitochondria-targeted vectors to deliver other compounds to mitochondria.

Forward-looking Statements

This press release contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Such forward-looking statements include those regarding Stealth BioTherapeutics’ expectations for SBT-272 preclinical data and Phase 1 clinical development efforts, and planned SBT-272 toxicology studies. Statements that are not historical facts, including statements about Stealth BioTherapeutics’ beliefs, plans and expectations, are forward-looking statements. The words “anticipate,” “expect,” “hope,” “plan,” “potential,” “possible,” “will,” “believe,” “estimate,” “intend,” “may,” “predict,” “project,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Stealth BioTherapeutics may not actually achieve the plans, intentions or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements as a result of known and unknown risks, uncertainties and other important factors, including: Stealth BioTherapeutics’ ability to obtain additional funding and to continue as a going concern; the impact of the COVID-19 pandemic; the ability to successfully demonstrate the efficacy and safety of Stealth BioTherapeutics’ product candidates and future product candidates; the preclinical and clinical results for Stealth BioTherapeutics’ product candidates, which may not support further development and marketing approval; the potential advantages of Stealth BioTherapeutics’ product candidates; the content and timing of decisions made by the FDA, the EMA or other regulatory authorities, investigational review boards at clinical trial sites and publication review bodies, which may affect the initiation, timing and progress of preclinical studies and clinical trials of Stealth BioTherapeutics product candidates; Stealth BioTherapeutics’ ability to obtain and maintain requisite regulatory approvals and to enroll patients in its planned clinical trials; unplanned cash requirements and expenditures; competitive factors; Stealth BioTherapeutics’ ability to obtain, maintain and enforce patent and other intellectual property protection for any product candidates it is developing; and general economic and market conditions. These and other risks are described in greater detail under the caption “Risk Factors” included in the Stealth BioTherapeutics’ most recent Annual Report on Form 20-F filed with the Securities and Exchange Commission (“SEC”), as well as in any future filings with the SEC. Forward-looking statements represent management’s current expectations and are inherently uncertain. Except as required by law, Stealth BioTherapeutics does not undertake any obligation to update forward-looking statements made by us to reflect subsequent events or circumstances.

Investor Relations 
Stern Investor Relations 
Janhavi Mohite, 212-362-1200

SOURCE Stealth BioTherapeutics Inc.