Broad Efficacy and Improved Safety Profile of HyBryte™ Presented at Society for Investigative Dermatology Virtual Meeting

Rhea-AI Summary

On May 4, 2021, Soligenix (Nasdaq: SNGX) announced positive results from the Phase 3 FLASH study concerning HyBryte™ (SGX301) for treating cutaneous T-cell lymphoma (CTCL). During the Society for Investigative Dermatology meeting, data revealed that 49% of patients achieved a significant reduction in lesions after 18 weeks. HyBryte™ demonstrated fewer severe side effects than current therapies and showed a low 5% drop-out rate due to adverse events. The study marked the largest of its kind, suggesting HyBryte™ could fulfill a critical need for safer CTCL treatments.

Positive

• 49% of patients achieved at least a 50% reduction in lesions after 18 weeks (p<0.0001).
• 5% overall drop-out rate attributed to adverse events, lower than typical in early-stage CTCL trials.
• HyBryte™ demonstrated statistically significant efficacy in treating both plaque and patch lesions.
• Considered safer than currently available therapies, with no systemic absorption or risk of DNA damage.

Negative

• None.

PRINCETON, N.J., May 4, 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 Ellen Kim, MD, Medical Director, Dermatology Clinic, Perelman Center for Advanced Medicine, Professor of Dermatology at the Hospital of the University of Pennsylvania, and the Lead Principal Investigator for the Phase 3 FLASH (Fluorescent Light Activated Synthetic Hypericin) study, presented confirmatory data at the Society for Investigative Dermatology (SID) Virtual Meeting, held May 3-8, 2021.  The presentation was selected to be shown during a Concurrent Mini-Symposium for Patient-Targeted Research. The presented data demonstrated the ability of HyBryte™ (SGX301) to treat both patch and plaque disease, including generating complete disease responses, while being associated with fewer and less severe adverse events than other currently approved skin-directed therapies for cutaneous T-cell lymphoma (CTCL). 

Oral Presentation:

Topical hypericin ointment photodynamic therapy is effective and safe in CTCL (FLASH study) Dr. Kim's presentation is archived on the SID Virtual Meeting site and will be accessible via registration until May 31, 2021.  The abstract is available here and attendees can register to see the presentation here.

Key Highlights:

• HyBryte™ is activated by visible light at a wavelength of 500-650 nm, which provides deeper dermal penetration than ultraviolet (UV) spectrum light. This resulted in statistically significant clinical responses observed in patches as well as deeper plaque lesions, which are typically more difficult to treat and generally less responsive to UV light therapy.
• In addition to its demonstrated, statistically significant efficacy which ultimately led to 49% of patients achieving at least a 50% reduction in their lesions (graded using a standard measurement of dermatologic lesions, the CAILS score) after 18 weeks of therapy (p<0.0001), complete responses of all treated index lesions were also shown to occur.  These complete responses increased in frequency as treatment with HyBryte™ continued and photographs demonstrating this response were reviewed.
• Compared to other, second-line, approved drugs for the treatment of CTCL, HyBryte™ demonstrated significantly less safety concerns. This was reflected in the low rate of study discontinuation attributed to adverse events which showed only a 5% overall drop-out rate during the treatment phase in HyBryte™ treated patients, lower than typically observed in other early stage CTCL trials. 

"Additional CTCL therapies with fewer and less severe side effects are desperately needed in our field," noted Dr. Kim. "I believe the efficacy and safety we saw HyBryte™ demonstrate in this trial proves that it can help us fill that need.  This study was the largest multicenter, randomized, double-blind, placebo-controlled skin directed therapy study in MF/CTCL (mycosis fungoides/cutaneous T-cell lymphoma) to date and I would like to thank all site investigators, and especially our patients, for their contributions to developing this promising new therapy."

About the Society for Investigative Dermatology Virtual Meeting

The SID meeting is an annual meeting, dedicated to a broad range of dermatology related topics, as described here.  SID's mission is to advance the sciences relevant to skin diseases through education, advocacy and scholarly exchange of scientific information.

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 that is taken up by the malignant T-cells, and then activated by visible 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 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 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<0.0001 vs the placebo treatment rate in Cycle 1). Comparison of the 12-week and 6-week treatment groups also revealed a statistically significant improvement (p<0.0001) between the two groups, indicating that continued treatment results in better outcomes.  HyBryte™ continued to be safe and well tolerated. Additional analyses also indicated that HyBryte™ is equally effective in treating both plaque (response 42%, p<0.0001 relative to placebo treatment in Cycle 1) and patch (response 37%, p=0.0009 relative to placebo treatment in Cycle 1) lesions of CTCL, a particularly relevant finding given the historical difficulty in treating plaque lesions in particular.

The third (optional) treatment cycle (Cycle 3) was focused on safety and all patients could elect to receive HyBryte™ treatment of all their lesions. Of note, 66% of patients elected to continue with this optional compassionate use / safety cycle of the study. Of the subset of patients that received HyBryte™ throughout all 3 cycles of treatment, 49% of them demonstrated a treatment response (p<0.0001 vs patients receiving placebo in Cycle 1). Moreover, in a subset of patients evaluated in this cycle, it was demonstrated that HyBryte™ is not systemically available, consistent with the general safety of this topical product observed to date. At the end of Cycle 3, HyBryte™ continued to be well tolerated despite extended and increased use of the product to treat multiple lesions. Follow-up visits were completed in Q4 2020, and the clinical study report to support the NDA is in the process of being finalized.   

Overall safety of HyBryte™ is a critical attribute of this treatment and was monitored throughout the three treatment cycles (Cycles 1, 2 and 3) and the 6-month follow-up period.  HyBryte's™ mechanism of action is not associated with DNA damage, making it a safer alternative than currently available therapies, all of which are associated with significant and sometimes fatal, side effects.  Predominantly these include the risk of melanoma and other malignancies, as well as the risk of significant skin damage and premature skin aging.  Currently available treatments are only approved in the context of previous treatment failure with other modalities and there is no approved front-line therapy available.  Within this landscape, treatment of CTCL is strongly motivated by the safety risk of each product.  HyBryte™ potentially represents the safest available efficacious treatment for CTCL.  With no systemic absorption, a compound that is not mutagenic and a light source that is not carcinogenic, there is no evidence to date of any potential safety issues. 

The Phase 3 CTCL clinical study was partially funded by the National Cancer Institute via a Phase II SBIR grant (#1R44CA210848-01A1) awarded to Soligenix, Inc.    

About Soligenix, Inc.

Soligenix is a late-stage biopharmaceutical company focused on developing and commercializing products to treat rare diseases where there is an unmet medical need. Our Specialized BioTherapeutics business segment is developing and moving toward potential commercialization of HyBryte™ (SGX301 or synthetic hypericin) as a novel photodynamic therapy utilizing safe visible light for the treatment of cutaneous T-cell lymphoma (CTCL). With a successful Phase 3 study completed, regulatory approval is being sought and commercialization activities for this product candidate are being advanced initially in the U.S.  Development programs in this business segment also include our first-in-class innate defense regulator (IDR) technology, dusquetide (SGX942) for the treatment of inflammatory diseases, including oral mucositis in head and neck cancer, and proprietary formulations of oral beclomethasone 17,21-dipropionate (BDP) for the prevention/treatment of gastrointestinal (GI) disorders characterized by severe inflammation including pediatric Crohn's disease (SGX203) and acute radiation enteritis (SGX201).

Our Public Health Solutions business segment includes active development programs for RiVax^®, our ricin toxin vaccine candidate, and SGX943, our therapeutic candidate for antibiotic resistant and emerging infectious disease, and our vaccine programs targeting filoviruses (such as Marburg and Ebola) and CiVax™, our vaccine candidate for the prevention of COVID-19 (caused by SARS-CoV-2). The development of our vaccine programs incorporates the use of our proprietary heat stabilization platform technology, known as ThermoVax^®. To date, this business segment has been supported with government grant and contract funding from the National Institute of Allergy and Infectious Diseases (NIAID), the Defense Threat Reduction Agency (DTRA) and the Biomedical Advanced Research and Development Authority (BARDA).

For further information regarding Soligenix, Inc., please visit the Company's website at www.soligenix.com.

This press release may contain forward-looking statements that reflect Soligenix, Inc.'s current expectations about its future results, performance, prospects and opportunities, including but not limited to, potential market sizes, patient populations and clinical trial enrollment.  Statements that are not historical facts, such as "anticipates," "estimates," "believes," "hopes," "intends," "plans," "expects," "goal," "may," "suggest," "will," "potential," or similar expressions, are forward-looking statements.  These statements are subject to a number of risks, uncertainties and other factors that could cause actual events or results in future periods to differ materially from what is expressed in, or implied by, these statements, such as experienced with the COVID-19 outbreak.  Soligenix cannot assure you that it will be able to successfully develop, achieve regulatory approval for or commercialize products based on its technologies, particularly in light of the significant uncertainty inherent in developing therapeutics and vaccines against bioterror threats, conducting preclinical and clinical trials of therapeutics and vaccines, obtaining regulatory approvals and manufacturing therapeutics and vaccines, that product development and commercialization efforts will not be reduced or discontinued due to difficulties or delays in clinical trials or due to lack of progress or positive results from research and development efforts, that it will be able to successfully obtain any further funding to support product development and commercialization efforts, including grants and awards, maintain its existing grants which are subject to performance requirements, enter into any biodefense procurement contracts with the U.S. Government or other countries, that it will be able to compete with larger and better financed competitors in the biotechnology industry, that changes in health care practice, third party reimbursement limitations and Federal and/or state health care reform initiatives will not negatively affect its business, or that the U.S. Congress may not pass any legislation that would provide additional funding for the Project BioShield program. In addition, there can be no assurance as to the timing or success of any of its clinical/preclinical trials.  Despite the statistically significant result achieved in the HyBryte™ (SGX301) Phase 3 clinical trial for the treatment of cutaneous T-cell lymphoma, there can be no assurance that a marketing authorization from the FDA or EMA will be successful.  Further, there can be no assurance that RiVax^® will qualify for a biodefense Priority Review Voucher (PRV) or that the prior sales of PRVs will be indicative of any potential sales price for a PRV for RiVax^®. Also, no assurance can be provided that the Company will receive or continue to receive non-dilutive government funding from grants and contracts that have been or may be awarded or for which the Company will apply in the future. These and other risk factors are described from time to time in filings with the Securities and Exchange Commission, including, but not limited to, Soligenix's reports on Forms 10-Q and 10-K.  Unless required by law, Soligenix assumes no obligation to update or revise any forward-looking statements as a result of new information or future events.

 

View original content:http://www.prnewswire.com/news-releases/broad-efficacy-and-improved-safety-profile-of-hybryte-presented-at-society-for-investigative-dermatology-virtual-meeting-301282870.html

SOURCE Soligenix, Inc.

FAQ

What were the results of the Phase 3 FLASH study presented by Soligenix?

The Phase 3 FLASH study showed that 49% of patients treated with HyBryte™ (SGX301) achieved at least a 50% reduction in lesions after 18 weeks.

What is the safety profile of HyBryte™ according to the recent findings?

HyBryte™ exhibited a low 5% drop-out rate due to adverse events, indicating a better safety profile compared to existing therapies for CTCL.

What percentage of patients responded to HyBryte™ treatment in the FLASH study?

In the FLASH study, 49% of patients demonstrated a significant response, achieving at least a 50% reduction in lesions.

How does HyBryte™ compare to other treatments for CTCL?

HyBryte™ has demonstrated fewer and less severe adverse events compared to currently approved skin-directed therapies for CTCL.

What designation has HyBryte™ received from the FDA?

HyBryte™ has received orphan drug and fast track designations from the FDA, facilitating its development process.