A phase 1 study is assessing the safety and tolerability of briquilimab in patients with lower-risk myelodysplastic syndrome.
Trial Name: A Phase 1 Open-label, Dose-escalation, Safety, and Tolerability Study of JSP191 as a Second-line Therapy in Subjects With Lower-Risk Myelodysplastic Syndrome (LR-MDS)
ClinicalTrials.gov Identifier: NCT05903274
Sponsor: Jasper Therapeutics, Inc.
Recruitment Contact: David Hinds, 650-549-1400, dhinds@jaspertherapeutics.com
Completion Date: July 2025
The first patient has been dosed in a phase 1 trial (NCT05903274) of briquilimab (JSP191) as second-line therapy in subjects with lower-risk myelodysplastic syndrome, according to Jasper Therapeutics.1
“LR-MDS patients often face limited treatment options that primarily focus on increasing blood cell production and survival rather than restoring normal blood homeostasis. By directly targeting and depleting the diseased stem cells, briquilimab has the potential to restore bone marrow to a healthier and more functional state, with the ultimate goal of improved long-term outcomes and quality of life. We are excited to test briquilimab in the LR-MDS setting,” said Jeffery Lancet, MD, chair of the Department of Malignant Hematology at Moffitt Cancer Center, in a press release.
Briquilimab is a novel antibody therapy targeting c-Kit to address diseases such as lower to intermediate risk myelodysplastic syndromes (LR-MDS), chronic spontaneous urticaria, and novel stem cell transplant conditioning regimes. Previous research has shown briquilimab to demonstrate efficacy and safety in over 130 patients with severe combined immunodeficiency, acute myeloid leukemia, MDS, sickle cell disease, and Fanconi anemia. In addition to these diseases, briquilimab is being developed as a transformational non-genotoxic conditioning agent for gene therapy.
In the open-label, single-arm phase 1 trial, the safety and tolerability of briquilimab is being evaluated a second-line therapy in patients with LR-MDS. A 3+3 dose-escalation design will be utilized in the trial to identify the maximum tolerated dose or optimal biologic dose, and the recommended phase 2 dose of briquilimab alone for this patient population with documented cytopenia such as red blood cell transfusion dependence, thrombocytopenia, or neutropenia.2
Up to 30 patients aged 18 years and older with MDS with IPSS-R very low-, low-, or intermediate-risk features with symptomatic cytopenias are expected to be enrolled in the trial and given treatment with briquilimab every 56 days for 4 consecutive cycles.
To be enrolled in the study, women of childbearing potential must agree to use an oral or implanted contraceptive, a double-barrier method of birth control, or an intrauterine device upon enrollment and through 3 months after receiving the last dose of briquilimab, and women not of childbearing potential must be postmenopausal or surgically sterilized and are required to have a negative serum pregnancy test upon entry in the study. For male patients, they are required to be surgically sterile or willing to use contraception upon enrollment and through 3 months after receiving the last dose of briquilimab.
The trial is being conducted at Moffitt Cancer Center in Tampa, FL, and has an estimated study completion date of July 2025.
“The initiation of this trial in LR-MDS represents a significant milestone in our briquilimab development program,” said Ronald Martell, president, and chief executive officer of Jasper, in the press release.1 “To date, the potential of briquilimab has been clinically assessed across five transplant indications and we are excited to explore its potential as a treatment option for a chronic disease such as LR-MDS. This trial underscores our commitment to improving outcomes and quality of life for patients with rare and chronic diseases driven by mast and stem cells.”
