FDA to Review Additional Phase III Study Evaluating Synthetic Hypericin for CTCL

The US Food and Drug Administration (FDA) has received a request to initiate formal discussions, in the form of a Type A Meeting, regarding the design of a second phase III pivotal study evaluating synthetic hypericin in the treatment of early-stage cutaneous T-cell lymphoma (CTCL).

The proposed second phase III study comes in the wake of the recently published phase III FLASH trial, in which a total of 16% of the patients with stage IA, IB, or IIA CTCL receiving synthetic hypericin achieved at least a 50% reduction in their lesions compared with 4% of patients in the placebo group at eight weeks (P=.04) during the first treatment cycle, which was the primary endpoint. The FLASH trial also found the synthetic hypericin treatment to be safe and well tolerated.

Hypericin sodium is a novel photodynamic therapy that utilizes visible light for activation. It is topically applied to skin lesions, taken up by malignant T cells, and then activated by visible light 24 hours later. Photoactivated hypericin has demonstrated significant antiproliferative effects on activated normal human lymphoid cells and inhibited growth of malignant T cells isolated from patients with CTCL. The treatment approach avoids the risk of secondary malignancies (including melanoma) inherent with the frequently employed DNA-damaging drugs and other phototherapies that are dependent on ultraviolet exposure, according to the manufacturer.

Source: Soligenix, April 2023