PRINCETON, N.J., Nov. 8, 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 it has been granted a Pediatric Investigation Plan (PIP) product-specific waiver from the Medicines and Healthcare products Regulatory Agency (MHRA) for HyBryte™ (SGX301 or synthetic hypericin), which has successfully concluded a Phase 3 pivotal clinical study for the treatment of early stage cutaneous T-cell lymphoma (CTCL).
The waiver was provided for all subsets of the pediatric population from birth to less than 18 years of age on the grounds that clinical studies in this rare population are not feasible. Earlier this year the European Medicines Agency (EMA) also granted a waiver to the Pediatric Investigational Plan requirements for the European Union (EU). With the withdrawal of the United Kingdom (UK) from the EU effective January 1, 2021, the MHRA became the UK's standalone medicines and medical devices regulator.
"This achievement is an important regulatory milestone as we move forward with marketing applications worldwide," stated Christopher J. Schaber, PhD, President and Chief Executive Officer of Soligenix. "The PIP waiver allows us to work towards advancing a marketing authorization application (MAA) in the UK in a more cost-effective manner since we will not need to expend resources to conduct a pediatric clinical study."
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 U.S. Food and Drug Administration, as well as orphan designation from the EMA.
The 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