Trethera Announces FDA Orphan Drug Designation Granted to TRE-515 for the Treatment of Demyelinating Optic Neuritis

LOS ANGELES, Aug. 09, 2022 (GLOBE NEWSWIRE) -- Trethera Corporation (“Trethera”), a clinical stage biopharmaceutical company committed to developing novel drugs targeting nucleotide metabolism for the treatment of cancer and autoimmune diseases, announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Status (ODS) to TRE-515 for the treatment of optic neuritis (ON). ON is a rare autoimmune disease where patients rapidly lose vision in one or both eyes with 1 in 10 patients never fully recovering their eyesight. TRE-515 is a first-in-class drug targeting the enzyme deoxycytidine kinase (dCK).

Representative stained sections of the optic nerve from mice. Arrows point to regions of leukocyte infiltration.
Figure 1: Representative stained sections of the optic nerve from mice. Arrows point to regions of leukocyte infiltration.

“The FDA designation for the treatment of ON complements our existing exclusive ODS for acute disseminated encephalomyelitis (ADEM) and provides key external validation that continues to showcase the strength of our scientific data,” said Dr. Ken Schultz, Trethera Chairman and CEO. “TRE-515 is developing an impressive resume for potential treatments of demyelinating autoimmune diseases.” ADEM is an autoimmune disease in which the immune system damages myelin in the central nervous system, leading patients to become paralyzed and causing death in some cases.

Over 100,000 cases of ON occur annually in the US and have a close association with multiple sclerosis (MS). Although steroids accelerate the rate of ON recovery and limit conversion to MS in the first two years, steroids have no effect on long-term visual outcomes or conversion to MS as measured after 5 years.   “Inflammation damaging the protective myelin coating around the optic nerve causes ON, leading to pain and vision loss. Targeting dCK with TRE-515 could limit this inflammation,” said Dr. Peter Clark, member of the Trethera Scientific Advisory Board.

“For some patients, ON can be self-resolving, but for others ON can lead to lifelong disability.  In all ON cases, the threat of future conversion to MS remains.  Any drug that could improve these outcomes for patients would be game changing. TRE-515 could potentially significantly benefit ON patients beyond the available therapeutic options, especially those taking long-term steroids,” said Trethera Scientific Advisory Board member Dr. Larry Steinman.

The FDA's Orphan Drug program is designed to advance the development of drugs that treat a condition affecting 200,000 or fewer US patients annually. ODS is given to medicinal products that represent a significant benefit over existing treatments and are intended for the treatment of a disease that is life-threatening or chronically debilitating. The ODS designation qualifies Trethera for certain incentives, which include FDA assistance in designing clinical trials, access to the FDA Orphan Drug Grants Program, exemption from the drug approval application fee and eligibility for seven years of marketing exclusivity.

Sources: Bennett 2019; Cleveland Clinic 2021; Yang 2017; Wilhelm 2015

About Trethera

Trethera is a clinical stage privately held biopharmaceutical company dedicated to pioneering the development of novel treatments for autoimmune diseases and cancers. Founded by prominent UCLA scientists, Trethera is led by experienced management and board members. Trethera's innovative approach to targeting nucleotide metabolism led to the development of TRE-515, an orally taken capsule twice designated by the FDA as an Orphan Drug. TRE-515 is a first-in-class clinical stage drug that inhibits deoxycytidine kinase (dCK), the rate-limiting enzyme in the nucleoside salvage pathway, one of two biosynthetic pathways that generate DNA precursors. It is believed that some forms of cancer may be preferentially dependent on the salvage pathway to support tumor growth. Certain autoimmune diseases might also respond to TRE-515 treatment. Trethera is developing TRE-515 for use as a monotherapy or in combination, to precisely target a metabolic vulnerability of cancer or autoimmune diseases that will transform outcomes for patients.

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Note on Forward-Looking Statements

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