Soligenix, Inc.NASDAQ: SNGX

Soligenix Receives Conditional FDA Acceptance of Proposed Brand Name HyBryte™ for SGX301 in CTCL

· Issued by Soligenix, Inc. via PR Newswire

PRINCETON, N.J., April 7, 2021 /PRNewswire/ -- Soligenix, Inc. (Nasdaq: SNGX) (Soligenix or the Company), a late-stage biopharmaceutical company focused on developing and commercializing products to treat rare diseases where there is an unmet medical need, announced today that the U.S. Food and Drug Administration (FDA) has conditionally accepted HyBryte™ as the proposed brand name for SGX301 (synthetic hypericin), the Company's novel first-in-class photodynamic therapy for first-line treatment of early stage cutaneous T-cell lymphoma (CTCL).

The name HyBryte™ was developed in compliance with the FDA's Guidance for Industry, Contents of a Complete Submission for the Evaluation of Proprietary Names.  The FDA's conditional approval validates HyBryte™ as a proprietary name that is consistent with the FDA's goal of preventing medication errors and potential harm to the public by ensuring that only appropriate proprietary names are approved for use.  Final approval of the HyBryte™ brand name is conditioned on FDA approval of the product candidate, SGX301.

"We are pleased that the FDA has conditionally accepted the name HyBryte™ for SGX301," stated Christopher J. Schaber, PhD, President and Chief Executive Officer of Soligenix. "This is yet another important step towards U.S. commercialization, as we continue to focus on submission of the rolling new drug application (NDA) in 2Q 2021 for this first-in-class therapy.  SGX301 has already received Orphan Drug and Fast Track designations from the FDA.  Additionally, SGX301 was granted Orphan Drug designation from the European Medicines Agency (EMA) and Promising Innovative Medicine designation from the Medicines and Healthcare products Regulatory Agency in the United Kingdom."

About Cutaneous T-Cell Lymphoma (CTCL)

CTCL is a class of non-Hodgkin's lymphoma (NHL), a type of cancer of the white blood cells that are an integral part of the immune system.  Unlike most NHLs which generally involve B-cell lymphocytes (involved in producing antibodies), CTCL is caused by an expansion of malignant T-cell lymphocytes (involved in cell-mediated immunity) normally programmed to migrate to the skin.  These malignant cells migrate to the skin where they form various lesions, typically beginning as patches and may progress to raised plaques and tumors.  Mortality is related to the stage of CTCL, with median survival generally ranging from about 12 years in the early stages to only 2.5 years when the disease has advanced. There is currently no cure for CTCL.  Typically, CTCL lesions are treated and regress but usually return either in the same part of the body or in new areas.

CTCL constitutes a rare group of NHLs, occurring in about 4% of the approximate 700,000 individuals living with the disease.  It is estimated, based upon review of historic published studies and reports and an interpolation of data on the incidence of CTCL that it affects over 25,000 individuals in the U.S., with approximately 3,000 new cases seen annually.

About HyBryte™

HyBryte™ (SGX301) is a novel first-in-class photodynamic therapy utilizing safe visible light for activation.  The active ingredient in HyBryte™ is synthetic hypericin, a potent photosensitizer that is topically applied to skin lesions, is taken up by the malignant T-cells, and then activated by fluorescent light 16 to 24 hours later.  The use of visible light in the red-yellow spectrum has the advantage of penetrating more deeply into the skin (much more so than ultraviolet light) and therefore potentially treating deeper skin disease and thicker lesions. This treatment approach avoids the risk of secondary malignancies (including melanoma) inherent with the frequently employed DNA-damaging drugs and other phototherapy that are dependent on ultraviolet exposure.  Combined with photoactivation, hypericin has demonstrated significant anti-proliferative effects on activated normal human lymphoid cells and inhibited growth of malignant T-cells isolated from CTCL patients.  In a published Phase 2 clinical study in CTCL, patients experienced a statistically significant (p=0.04) improvement with topical hypericin treatment whereas the placebo was ineffective.  HyBryte™ has received orphan drug and fast track designations from the FDA, as well as orphan designation from the European Medicines Agency (EMA).

The Phase 3 FLASH (Fluorescent Light Activated Synthetic Hypericin) trial enrolled a total of 169 patients (166 evaluable) with Stage IA, IB or IIA CTCL. The trial consisted of three treatment cycles. Treatments were administered twice weekly for the first 6 weeks and treatment response was determined at the end of the 8th week of each cycle. In the first double-blind treatment cycle, 116 patients received HyBryte™ treatment (0.25% synthetic hypericin) and 50 received placebo treatment of their index lesions. A total of 16% of the patients receiving HyBryte™ achieved at least a 50% reduction in their lesions (graded using a standard measurement of dermatologic lesions, the CAILS score) compared to only 4% of patients in the placebo group at 8 weeks (p=0.04) during the first treatment cycle (primary endpoint). HyBryte™ treatment in the first cycle was safe and well tolerated.

In the second open-label treatment cycle (Cycle 2), all patients received HyBryte™ treatment of their index lesions. Evaluation of 155 patients in this cycle (110 receiving 12 weeks of HyBryte™ treatment and 45 receiving 6 weeks of placebo treatment followed by 6 weeks of HyBryte™ treatment), demonstrated that the response rate among the 12-week treatment group was 40% (p