Study Supported by $2.6 Million FDA Orphan Products Development Grant
PRINCETON, N.J., Jan. 14, 2025 /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 an interim update on the open-label, investigator-initiated study (IIS) evaluating extended HyBryte™ (synthetic hypericin) treatment for up to 12 months 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 Phase 3 FLASH (Fluorescent Light Activated Synthetic Hypericin) study for the treatment of early-stage CTCL. To date, nine patients have been enrolled and treated with HyBryte™ over a time period of up to 54 weeks. Patients have responded positively to HyBryte™ therapy, with over 70% (5 of the 6 subjects who have completed at least 18 weeks of therapy) already achieving "Treatment Success". Treatment Success is predefined in the study's protocol as a greater than or equal to 50% improvement in the cumulative mCAILS (modified Composite Assessment of Index Lesion Severity) score compared to Baseline. Of the five Treatment Successes, three were achieved within the first 12 weeks of treatment, with two patients achieving a "complete response" by 18 weeks. Of the remaining patients, two have recently started the study and two had to drop from the study for logistical reasons (e.g., need to care for an elderly parent), with one showing a substantial improvement (>30%) by their Week 18 visit. In addition, HyBryte™ appears to be safe and well tolerated in all patients.
"The complete response rate, consistent treatment response and safety profile across multiple clinical studies to date with HyBryte™ has been exciting to see," noted Dr. Kim, Principal Investigator of the IIS and Lead Investigator of the FLASH2 study. "In the first Phase 3 FLASH study, HyBryte™ was shown to be efficacious with a benign safety profile compared to the current therapies of steroids, chemotherapeutics and ultraviolet light in this chronic orphan disease. With limited treatment options, especially in the early stages of their disease, CTCL patients are often searching for alternative treatments. In our U.S. Food and Drug Administration (FDA)-funded study, initial results evaluating the expanded use of HyBryte™ in a "real world" treatment setting remain very promising, further supporting and extending results from the previous positive Phase 2 and 3 clinical trials. We look forward to continuing to work with the FDA to complete this study while we participate in the confirmatory Phase 3 placebo-controlled FLASH2 study."
"We are pleased with these recent study results and that the FDA is continuing to financially support the HyBryte™ program, giving patients an opportunity to access the therapy in an open-label setting," stated Christopher J. Schaber, PhD, President and Chief Executive Officer of Soligenix. "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. Following the initial Phase 3 FLASH study, which demonstrated the safety and efficacy of shorter courses of HyBryte™ therapy, we are pleased to see that continuing treatment for longer time periods is resulting in the anticipated improved outcomes for patients. As the body of compelling data continues to grow in support of this novel therapy, we look forward to continuing to work with Dr. Kim on this important study as well as advancing enrollment in the 80-patient confirmatory Phase 3 FLASH2 replication study. We will plan to provide additional updates on the IIS as data becomes 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 20 patients in the U.S. Patients have the potential to be treated for up to 12 months with twice a week dosing (visible light activation following ointment application by 24 ± 6 hours). The study also allows for potential transition to a "real-world" setting with home-use. The primary endpoint for the study is evaluating the number of treatment successes defined as ≥50% reduction in the cumulative mCAILS 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 safe, 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 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 (Cycle 1), 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 this 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