LY13 A confirmatory phase III multicentre, randomized, double-blind, placebo-controlled study of the efficacy of topical HyBryte™ (hypericin sodium) and visible-light activation for the treatment of cutaneous T-cell lymphoma: interim analysis results

Abstract

Early-stage cutaneous T-cell lymphoma (CTCL) is an indolent lymphoma of the skin. It has a high symptom burden and causes reduced quality of life from painful, itchy and unsightly lesions. The primary objective of this phase III study is to evaluate the ability of an 18-week course of HyBryte™ (research name SGX301), activated by visible light, to induce a treatment response in patients with patch- or plaque-phase CTCL compared with patients receiving placebo and visible light. HyBryte 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 and is taken up by the malignant T cells, and then activated by safe, visible light approximately 24 h later. Treatment response is defined as an improvement of ≥ 50% in the mCAILS score (Modified Composite Assessment of Index Lesion Severity) summed over the three to five index lesions compared with the patient’s baseline evaluation. FLASH2 is a randomized, double-blind, placebo-controlled, multicentre study that is enrolling approximately 80 patients with early-­stage CTCL. The independent study data monitoring committee (DMC) is empowered to conduct one formal interim analysis when approximately 60% (n = 48) of the total patients have completed the primary endpoint evaluation (i.e. week 18 or before). As this enrolment has been reached, the DMC meeting will be at the end of April 2026. Efficacy and safety results from this meeting will be presented. One DMC meeting was conducted already on safety data alone. It concluded that there are no safety concerns with the ongoing phase III study and that HyBryte has an acceptable safety profile that remains consistent with the safety data from all prior clinical studies.