Soligenix advances FLASH2 HyBryte trial toward interim readout, extends primary endpoint to 18 weeks

Soligenix pushes confirmatory HyBryte™ study toward interim readout as design emphasizes longer treatment

FLASH2 confirmatory trial centers on extended-treatment endpoint

Soligenix is advancing its confirmatory Phase 3 FLASH2 trial of HyBryte™ (synthetic hypericin) in early‑stage cutaneous T‑cell lymphoma (CTCL) and emphasizes an extended primary endpoint to capture improved responses with longer treatment. The 80‑patient, actively enrolling study largely replicates the design of the earlier successful FLASH study but shifts primary endpoint assessment from six weeks to 18 weeks based on evidence that prolonged therapy increases response rates. Management reports the blinded aggregate response rate remains consistent with the company’s November update and is higher than the estimate used to design the trial, which bolsters confidence in both the planned interim and final analyses.

Enrollment progress and timing highlight upcoming milestones

As of Feb. 10 the company has enrolled 66 patients and anticipates an interim analysis in the second quarter, with top‑line results expected in the second half of 2026. Soligenix describes patient enrollment as progressing nicely and frames 2026 as a key year for clinical progress: the interim readout is portrayed as a pivotal near‑term milestone that will inform regulatory and development strategy. The company’s leadership underscores that the trial’s replication of prior positive findings, coupled with the longer endpoint, is intended to more fully reflect “real world” continuous treatment effects.

Trial design choices reflect prior supportive data

Management cites evidence from prior studies indicating that longer durations of HyBryte™ therapy yield improved outcomes, and states that FLASH2’s endpoint adjustment is a direct response to that evidence. By preserving the core elements that produced success in the first FLASH study while extending the assessment window, Soligenix is aiming to produce a confirmatory data set that supports broader clinical and regulatory evaluation for early‑stage CTCL.

Supporting investigator data underscore extended‑treatment benefit

Separately, an open‑label investigator‑initiated study at the University of Pennsylvania led by Dr. Ellen Kim evaluates continuous HyBryte™ treatment up to 54 weeks and reports that after 18 weeks 75% of evaluable patients attain “Treatment Success,” with three of eight achieving complete response. Soligenix cites this real‑world investigator data as reinforcing the rationale for FLASH2’s longer primary endpoint.

Company strategic review and management outlook

While advancing FLASH2, Soligenix is evaluating strategic options including partnerships and merger and acquisition opportunities to support development and commercialization. President and CEO Dr. Christopher J. Schaber thanks supporters and patients, reiterates 2026 as an important year for both clinical milestones and strategic evaluation, and expresses optimism about the approaching interim analysis.