Soligenix, Inc.NASDAQ: SNGX

HyBryte™ Expanded Treatment Trial in Cutaneous T-Cell Lymphoma Opens Enrollment

· Issued by Soligenix, Inc. via PR Newswire

Study Supported by $2.6 Million FDA Orphan Products Development Grant

PRINCETON, N.J., Aug. 10, 2023 /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 patient enrollment has been opened for the investigator-initiated study (IIS) at the University of Pennsylvania, supported by a $2.6 million Orphan Products Development grant award by the U.S. Food and Drug Administration (FDA).  The IIS will evaluate the expanded treatment, including up to 12 months of treatment, with HyBryte™ (synthetic hypericin) in patients with early-stage cutaneous T-cell lymphoma (CTCL). The trial is sponsored by Ellen Kim, MD, Director, Penn Cutaneous Lymphoma Program, Vice Chair of Clinical Operations, Dermatology Department, and Professor of Dermatology at the Hospital of the University of Pennsylvania who was a leading enroller in the recently published positive Phase 3 FLASH (Fluorescent Light Activated Synthetic Hypericin) study in the treatment of early-stage CTCL.

(PRNewsfoto/Soligenix, Inc.)

"In the Phase 3 FLASH study, HyBryte™ was shown to be efficacious with a promising safety profile. CTCL patients are often searching for alternative treatments, with limited options especially for early-stage disease. HyBryte™ offers a distinct treatment option which patients found extremely useful and continue to specifically request. We look forward to demonstrating the expanded use of HyBryte™ in a "real world" setting and thank both the FDA and Soligenix for their support of this study," noted Dr. Kim, principal investigator of the IIS, RW-HPN-MF-01.

"We are pleased the FDA is supporting the HyBryte™ program and giving patients an opportunity to access the therapy in an open-label setting," stated Christopher J. Schaber, President and CEO of Soligenix, Inc. "CTCL is an incredibly difficult to treat orphan disease and remains an area of unmet medical need with a very limited number of safe and effective treatment options.  With the demonstration of statistical significance in the primary endpoint and continued improvement in treatment response with extended treatment in our published Phase 3 FLASH study, we are continuing discussions with FDA on the design of a second confirmatory Phase 3 study. This IIS has the potential to augment the expanding safety database for synthetic hypericin, as well as provide further real-world evidence into the practical use of HyBryte™ once commercially available."

The clinical study RW-HPN-MF-01, "Assessment of Treatment with Visible Light Activated Synthetic Hypericin Ointment in Mycosis Fungoides Patients" is designed as an open-label, multicenter clinical trial enrolling approximately 50 patients at select high enrolling clinical centers that participated in the Phase 3 FLASH study.  Patients have the potential to be treated for up to 12 months with twice a week dosing (visible light activation to follow ointment application by 24 ± 6 hours).  The study also allows for potential transition to the home-use setting.  The primary endpoint for the study will be evaluating the number of treatment successes defined as ≥50% reduction in the cumulative CAILS (Composite Assessment of Index Lesion Severity) score from baseline to end of the treatment.

About HyBryte™

HyBryte™ (research name 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 that is taken up by the malignant T-cells, and then activated by visible light approximately 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 plaques and 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 recently published Phase 3 FLASH 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