Efficacy and Safety of Topical Hypericin Photodynamic Therapy for Early-Stage Cutaneous T-Cell Lymphoma (Mycosis Fungoides)
Authors: Kim Ellen J. , Mangold Aaron R. , DeSimone Jennifer A. , Wong Henry K. , Seminario-Vidal Lucia , Guitart Joan , Appel James , Geskin Larisa , Lain Edward , Korman Neil J. , Zeitouni Nathalie , Nikbakht Neda , Dawes Kenneth , Akilov Oleg , Carter Joi , Shinohara Michi , Kuzel Timothy M. , Piette Warren , Bhatia Neal , Musiek Amy , Pariser David , Kim Youn H. , Elston Dirk , Boh Erin , Duvic Madeleine , Huen Auris , Pacheco Theresa , Zwerner Jeffrey P. , Lee Seung Tae , Girardi Michael , Querfeld Christiane , Bohjanen Kimberly , Olsen Elise , Wood Gary S. , Rumage Adam , Donini Oreola , Haulenbeek Andrea , Schaber Christopher J. , Straube Richard , Pullion Christopher , Rook Alain H. , Poligone Brian 
Published: July 2022

Importance

Given that mycosis fungoides−cutaneous T-cell lymphoma (MF/CTCL) is chronic, there is a need for additional therapies with minimal short- and long-term adverse effects. Topical synthetic hypericin ointment, 0.25%, activated with visible light is a novel, nonmutagenic photodynamic therapy (PDT).

Objectives

To determine the efficacy and safety of topical synthetic hypericin ointment, 0.25%, activated with visible light as a nonmutagenic PDT in early-stage MF/CTCL.

Design, Settings, and Participants

This was a multicenter, placebo-controlled, double-blinded, phase 3 randomized clinical trial (FLASH study) conducted from December 2015 to November 2020 at 39 academic and community-based US medical centers. Participants were adults (≥18 years) with early-stage (IA-IIA) MF/CTCL.

Interventions

In cycle 1, patients were randomized 2:1 to receive hypericin or placebo to 3 index lesions twice weekly for 6 weeks. In cycle 2, all patients received the active drug for 6 weeks to index lesions. In cycle 3 (optional), both index and additional lesions received active drug for 6 weeks.

Main Outcomes and Measures

The primary end point was index lesion response rate (ILRR), defined as 50% or greater improvement in modified Composite Assessment of Index Lesion Severity (mCAILS) score from baseline after 6 weeks of therapy for cycle 1. For cycles 2 and 3, open label response rates were secondary end points. Adverse events (AEs) were assessed at each treatment visit, after each cycle, and then monthly for 6 months. Data analyses were performed on December 21, 2020.

Results

The study population comprised 169 patients (mean [SD] age, 58.4 [16.0] years; 96 [57.8%] men; 120 [72.3%] White individuals) with early-stage MF/CTCL. After 6 weeks of treatment, hypericin PDT was more effective than placebo (cycle 1 ILRR, 16% vs 4%; P = .04). The ILRR increased to 40% in patients who received 2 cycles of hypericin PDT (P &lt; .001 vs cycle 1 hypericin) and to 49% after 3 cycles (P &lt; .001 vs cycle 1 hypericin). Significant clinical responses were observed in both patch and plaque type lesions and were similar regardless of age, sex, race, stage IA vs IB, time since diagnosis, and number of prior therapies. The most common treatment-related AEs were mild local skin (13.5%-17.3% across cycles 1-3 vs 10.5% for placebo in cycle 1) and application-site reactions (3.2%-6.9% across cycles 1-3 vs 4% for placebo in cycle 1). No drug-related serious AEs occurred.

Conclusion and Relevance

The findings of this randomized clinical trial indicate that synthetic hypericin PDT is effective in early-stage patch and plaque MF/CTCL and has a favorable safety profile.

Trial Registration

ClinicalTrials.gov Identifier: NCT02448381