HyBryte Demonstrates Continued Efficacy Among Patients With Early-Stage Cutaneous T-Cell Lymphoma

Soligenix Inc. today announced positive interim results for its 12-month investigator-initiated study of synthetic hypericin (HyBryte) in patients with early-stage cutaneous T-cell lymphoma (CTCL).¹

The open-label trial, sponsored by Ellen Kim, MD, of the Penn Cutaneous Lymphoma Program, aims to explore the safety and efficacy of HyBryte over a year long period.

Plaque stage mycosis fungoides | Image Credit: © Te Whatu Ora; DermNet

To date, 9 patients have been enrolled in the study, with 6 completing at least 18 weeks of therapy. Over 70% of these participants have achieved “treatment success,” defined as a ≥50% reduction in the cumulative modified Composite Assessment of Index Lesion Severity score from baseline.

Among these successes, 3 patients showed significant improvement within the first 12 weeks. Furthermore, 2 participants achieved complete responses by the 18-week mark.

Of the remaining patients, 2 recently began the study, while 2others discontinued for personal reasons unrelated to treatment efficacy or safety. Notably, 1 of these individuals exhibited a >30% improvement by their week 18 visit prior to withdrawing their participation.

HyBryte continues to demonstrate a favorable safety profile, with no serious adverse events reported among the participants. This finding aligns with prior clinical studies, including the pivotal phase 3 FLASH, or Fluorescent Light Activated Synthetic Hypericin, trial, which established the therapy’s efficacy and tolerability in a more limited treatment duration.²

Kim, the study’s principal investigator, emphasized the potential of HyBryte to address the unmet needs of patients with CTCL, particularly those in the early stages of the disease.

"The complete response rate, consistent treatment response and safety profile across multiple clinical studies to date with HyBryte has been exciting to see," Kim said in a news release.¹ "With limited treatment options, especially in the early stages of their disease, CTCL patients are often searching for alternative treatments. In our US Food and Drug Administration-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."

The clinical trial, titled "Assessment of Treatment with Visible Light Activated Synthetic Hypericin Ointment in Mycosis Fungoides Patients" (RW-HPN-MF-01), aims to enroll approximately 20 participants across multiple study centers. The protocol includes twice-weekly applications of HyBryte, followed by visible light activation within 24 ± 6 hours. Patients may continue treatment for up to 12 months, transitioning to a home-use setting as appropriate.

In late 2024, Soligenix announced it would be launching a European Advisory Board to guide the study, which is being conducted across sites in Europe and the US.³ In addition to CTCL, Soligenix is investigating HyBryte for conditions like mild to moderate psoriasis. Early studies suggest potential for broader therapeutic use.⁴

Christopher Schaber, PhD, president and CEO of Soligenix, expressed optimism about the interim results.

"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," Schaber said.¹ "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."

References

1. HyBryte expanded treatment continues to demonstrate positive outcomes in early-stage cutaneous T-cell lymphoma. News release. PR Newswire. January 14, 2025. Accessed January 14, 2025. https://www.prnewswire.com/news-releases/hybryte-expanded-treatment-continues-to-demonstrate-positive-outcomes-in-early-stage-cutaneous-t-cell-lymphoma-302350395.html
2. Kim EJ, Mangold AR, DeSimone JA, et al. Efficacy and safety of topical hypericin photodynamic therapy for early-stage cutaneous T-cell lymphoma (mycosis fungoides): the FLASH phase 3 randomized clinical trial. JAMA Dermatol. 2022;158(9):1031-1039. doi:10.1001/jamadermatol.2022.2749
3. Soligenix Announces Formation of European Medical Advisory Board for Cutaneous T-Cell Lymphoma. News release. Soligenix. November 19, 2024. Accessed January 14, 2025. https://ir.soligenix.com/2024-11-19-Soligenix-Announces-Formation-of-European-Medical-Advisory-Board-for-Cutaneous-T-Cell-Lymphoma
4. Soligenix announces top-line results of the phase 2a study of SGX302 (synthetic hypericin) in patients with mild-to-moderate psoriasis. News release. PR Newswire. January 4, 2024. Accessed January 14, 2025. https://www.prnewswire.com/news-releases/soligenix-announces-top-line-results-of-the-phase-2a-study-of-sgx302-synthetic-hypericin-in-patients-with-mild-to-moderate-psoriasis-302025994.html#:~:text=Synthetic%20hypericin%20or%20HyBryte%E2%84%A2,caused%20by%20malignant%20T%2Dcells