Polaryx Therapeutics, Inc.: Polaryx Therapeutics Receives FDA Fast Track Designation for PLX-200 for Late-Infantile Neuronal Ceroid Lipofuscinosis (CLN2 Disease)

• Regulatory milestone supports advancement of the SOTERIA Phase 2 basket trial evaluating PLX-200 across multiple lysosomal storage disorders
  

PARAMUS, NJ, March 17, 2026 (GLOBE NEWSWIRE) -- Polaryx Therapeutics, Inc. (Nasdaq: PLYX), a clinical-stage biotechnology company developing disease-modifying therapies for rare pediatric lysosomal storage disorders ("LSDs"), today announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track Designation to PLX-200 for the treatment of Late-Infantile Neuronal Ceroid Lipofuscinosis (LINCL/CLN2 disease).

The Fast Track program is designed to facilitate and expedite the review of therapies intended to treat serious or life-threatening conditions with unmet medical need. Companies receiving Fast Track designation may benefit from more frequent interactions with the FDA and the potential for rolling review of a future marketing application.

"Receiving Fast Track designation represents an important regulatory milestone as we prepare to initiate the SOTERIA Phase 2 basket trial evaluating PLX-200 across multiple lysosomal storage disorders" said Alex Yang, Chair and Chief Executive Officer of Polaryx Therapeutics. "We appreciate the FDA's recognition of the potential of PLX-200 to address the significant unmet medical need in CLN2 disease and look forward to continued engagement with the agency as we advance development of this program."

Polaryx continues to advance the development of PLX-200 through SOTERIA, a phase 2, open-label, single-arm basket trial designed to evaluate the safety, tolerability, and clinical activity of PLX-200 across four rare lysosomal storage disorders: CLN2, CLN3, Krabbe disease, and Sandhoff disease.

About PLX-200

Polaryx's lead drug candidate, PLX-200, is an orally available compound comprised of gemfibrozil. Gemfibrozil is an FDA-approved lipid regulating agent in the fibrate family which has only been approved in a capsule form for adult patients with very high elevations of serum triglyceride levels to decrease serum triglycerides and very low-density lipoprotein cholesterol and increase high density lipoprotein cholesterol. The ability of gemfibrozil to cross the blood-brain barrier ("BBB") has also been documented in third-party preclinical trials and safe use of gemfibrozil in adults has also been well-established over several decades of clinical investigation and commercial use, which we believe accelerates clinical development and reduces associated costs. We believe the unique ability of PLX-200 to cross the BBB, along with its widely applicable mechanism of action, positions PLX-200 to potentially address the immense unmet need in multiple rare, catastrophic LSD indications.

About the SOTERIA Trial

SOTERIA is a Phase 2, open-label, single arm trial intended to assess the safety, tolerability, and clinical activity of Polaryx's lead drug candidate, PLX-200, in CLN2, CLN3, Krabbe disease, and Sandhoff disease, four different LSDs whose patient populations Polaryx believes represent approximately one quarter of the LSD population. SOTERIA is designed to be flexible, resource-efficient, and provide important data and information important to PLX-200's future clinical development. Polaryx received a safe to proceed letter in October 2025 from the FDA and plans to initiate SOTERIA in the third quarter of 2026 in trial sites in the United States as well as in Europe and Asia or other foreign jurisdictions. Designed with a high degree of flexibility, SOTERIA represents a resource-efficient opportunity to validate PLX-200's preclinical science across multiple LSDs while gathering data that will be invaluable in planning PLX-200's future development pathway, including the initiation of potentially pivotal trials. For the CLN2 and CLN3 cohorts, although the entire trial is open label, these cohorts will incorporate analyses comparing natural history data as a control arm to PLX-200's treated arm. A natural history study is a preplanned observational study intended to track the course of the disease. Should the data demonstrate compelling clinical activity, Polaryx may seek conditional marketing authorization.

About Polaryx Therapeutics

Polaryx Therapeutics, Inc. is a clinical-stage biotechnology company focused on developing patient-friendly small molecule and gene therapy treatments for rare orphan lysosomal storage disorders (LSDs). Founded in 2014, Polaryx seeks to deliver safe, effective, and patient-friendly treatments that address the underlying pathophysiology of these catastrophic diseases and their significant unmet need. Our approach integrates small molecule therapies, including a combination therapy, and a gene therapy, positioning us to potentially address both the genetic and downstream pathological features of LSDs. Our small molecule drug candidates share similar modes of action that have been demonstrated to address lysosomal dysfunction, neuroinflammation, and neuronal loss in our validated animal models that closely mimic human clinical phenotypes. Our most advanced product candidate, PLX-200, targets several LSDs and we intend to launch SOTERIA, a Phase 2 basket trial, to evaluate PLX-200's safety and efficacy. For more information, please visit www.polaryx.com.

Forward-Looking Statements

Certain statements in this press release may constitute "forward-looking statements" within the meaning of the federal securities laws, including, but not limited to, statements regarding: Polaryx's clinical development plans for PLX-200, including the timing for initiation of the SOTERIA trial. Words such as "may," "might," "will," "objective," "intend," "should," "could," "can," "would," "expect," "believe," "design," "estimate," "predict," "potential," "develop," "plan" or the negative of these terms, and similar expressions, or statements regarding intent, belief, or current expectations, are forward-looking statements. While Polaryx believes these forward-looking statements are reasonable, undue reliance should not be placed on any such forward-looking statements, which are based on information available to the company on the date of this release. These forward-looking statements are based upon current estimates and assumptions and are subject to various risks and uncertainties (including, without limitation, those set forth in Polaryx's filings with the U.S. Securities and Exchange Commission (the SEC), many of which are beyond the company's control and subject to change. Actual results could be materially different. Risks and uncertainties include: global macroeconomic conditions and related volatility, expectations regarding the initiation, progress, and expected results of Polaryx's clinical trials; expectations regarding the timing, completion and outcome of Polaryx's clinical trials; the timing or likelihood of regulatory filings and approvals; liquidity and capital resources; and other risks and uncertainties identified in Polaryx's Registration Statement on Form S-1, as amended, filed with the SEC on January 27, 2026 and subsequent disclosure documents Polaryx may file with the SEC. Polaryx claims the protection of the Safe Harbor contained in the Private Securities Litigation Reform Act of 1995 for forward-looking statements. Polaryx expressly disclaims any obligation to update or alter any statements whether as a result of new information, future events or otherwise, except as required by law.

Media Contact:

CORE IR
[phone]
[e-mail]

Investor Contact:

CORE IR
[phone]
[e-mail]