Philikos B.V., a Dutch biotechnology company, has enrolled the first patient in a Phase 1/2 clinical trial evaluating T-Guard for the treatment of diffuse cutaneous systemic sclerosis (dcSSc), the company announced on May 20, 2025. The trial represents a significant step toward addressing a serious autoimmune disorder with few effective treatment options.
The open-label, single-arm study (PHIL_TG-01; EU CT: 2024-517283-28-00) aims to assess both safety and preliminary efficacy of T-Guard in patients with early-stage dcSSc. The trial will enroll 12 adult patients diagnosed within the last three years whose disease remains refractory despite prior systemic immunosuppressive therapy.
"We are excited to initiate this trial, which represents a major step forward in bringing T-Guard to patients suffering from diffuse cutaneous systemic sclerosis, a significant unmet medical need where T-Guard may qualify for orphan drug designation," said Ypke van Oosterhout, Ph.D., Chief Executive Officer of Philikos.
Trial Design and Endpoints
The primary endpoint focuses on safety, measuring the incidence of grade 3 or higher adverse events from the first T-Guard infusion through 28 days after the last administration. T-Guard is administered as a short one-week treatment consisting of four infusions given every other day.
Secondary endpoints will track improvement in dcSSc disease using the Revised Composite Response Index in Systemic Sclerosis (CRISS) at 1, 3, 6, 9, and 12 months post-treatment initiation.
The study will initially enroll four patients before an independent Data Safety Monitoring Board (DSMB) assesses safety and preliminary efficacy. If the risk-benefit profile is favorable, the trial will expand to include all 12 planned participants. Interim data and DSMB recommendations are expected by the end of 2025.
Addressing a Significant Unmet Need
Systemic sclerosis affects approximately 200,000 patients across major markets, with 67,000 suffering from the more severe dcSSc form. The disease is characterized by vascular damage, skin tightening, and hardening of connective tissue (fibrosis) in various internal organs.
"With no widely accessible and safe disease-modifying treatments available, there is a high unmet medical need for effective new therapies for systemic sclerosis," explained Principal Investigator Madelon Vonk, M.D., Ph.D., Associate Professor of Systemic Sclerosis at Radboud University Medical Center. "T-Guard, with promising preclinical data and initial clinical results, has the potential to significantly impact patients suffering from this debilitating and life-threatening autoimmune disease characterized by inflammation and fibrosis."
Currently, hematopoietic stem cell transplantation (HSCT) is the only approach shown to halt the disease process. However, HSCT carries severe side effects and a 5-10% mortality risk, making it accessible to only a fraction of dcSSc patients.
T-Guard's Mechanism and Potential
T-Guard represents a novel approach to treating severe T-cell mediated conditions. The therapy combines toxin-conjugated monoclonal antibodies targeting CD3 and CD7 molecules on T cells and NK cells, designed to rapidly and safely reset the body's immune system.
Laboratory studies have demonstrated T-Guard's ability to eliminate disease-associated T cells and NK cells from the blood and tissues of SSc patients. Additionally, compassionate use of T-Guard in a patient with advanced dcSSc showed encouraging results.
"We strongly believe that T-Guard has the potential to be an alternative solution to an expensive and risky hematopoietic stem cell transplantation, the only curative treatment option today," van Oosterhout stated. "With its short treatment duration, targeted immune depletion, and anticipated good tolerability, T-Guard could offer a less invasive and more accessible option for a broader group of patients suffering from this devastating disease."
Philikos has previously generated promising late-stage clinical data with T-Guard in treating severe acute graft-versus-host disease, further supporting the therapy's potential in immune-mediated conditions.
About Philikos
Philikos is a privately held biotechnology company based in the Netherlands developing antibody-based therapies for severe immune disorders. The company's platform centers on T-Guard, which rebalances the immune system by depleting activated T cells and NK cells.
The company is backed by early-stage investors including Oost NL, Essential Investments, and Radboud University Medical Center, with which it maintains a strong research collaboration.
