Updated BEXMAB Phase I/II Data presented at ESMO 2025 shows further improvement, strengthening the clinical profile of bexmarilimab in treatment-naïve HR-MDS patients

Updated BEXMAB Phase I/II Data presented at ESMO 2025 shows further improvement, strengthening the clinical profile of bexmarilimab in treatment-naïve HR-MDS patients with an 85% ORR and a 45% CR rate, bolstered by pharmacodynamic insights

New biomarker data reveals strong correlation between target engagement and clinical response with 100% ORR in treatment-naïve, low blast count (<5%) patients

Key highlights:

Bexmarilimab and azacitidine combination resulted in an 85% objective response rate (ORR; 17/20 evaluable patients) and a 45% complete remission (CR) rate (9/20) in treatment-naïve patients with higher-risk myelodysplastic syndrome (HR-MDS)

55% (11/20) of treatment-naïve patients with HR-MDS showed full clearance of bone marrow (BM) blasts

Deeper BM engagement in treatment-naïve patients with <5% bone marrow blasts at baseline translated to 100% ORR, one of the best results ever reported in this patient population

23% of patients across the BEXMAB study were successfully bridged to a potentially curative stem cell transplant (SCT)

Faron will be hosting a virtual webinar to discuss the updated BEXMAB data presented at ESMO 2025 on 23 October at 4pm EEST/9am ET.

Turku, Finland– Faron Pharmaceuticals Ltd. (AIM: FARN, First North: FARON), a clinical-stage biopharmaceutical company focused on tackling cancers through novel immunotherapies, today announced that updated data from the Phase I/II BEXMAB study continues to show significant clinical activity for bexmarilimab. The findings, presented in an oral session at the European Society for Medical Oncology (ESMO) Congress 2025 by Dr. Mika Kontro from Helsinki University Hospital, not only confirm the high response rates seen in earlier analyses but also provide a clear pharmacodynamic rationale linking the drug’s mechanism of action directly to patient outcomes.

The BEXMAB study evaluates bexmarilimab (1, 3, or 6 mg/kg weekly in 28-day cycles), a first-in-class monoclonal antibody targeting the Clever-1 receptor, in combination with azacitidine, a standard-of-care hypomethylating agent (HMA). By blocking Clever-1, bexmarilimab reprograms macrophages in the bone marrow, enhancing anti-tumor immunity. The data presented at ESMO 2025 included 21 treatment-naïve (20 evaluable for efficacy) and 32 relapsed/refractory (r/r) HMA-failed patients with HR-MDS.

The updated data presented at ESMO 2025 reinforces the efficacy previously observed for the bexmarilimab and azacitidine combination. In 20 evaluable treatment-naïve patients, the study confirmed an 85% ORR and a 45% CR rate. These high response rates were observed in a difficult-to-treat population, where over 66% of patients were classified as high to very high risk at baseline. The combination also showed robust activity in patients with high-risk mutations like mTP53, achieving an ORR of 78%.

In the r/r HMA-failed population (n=32), the combination achieved a 63% ORR and a median overall survival (mOS) of 13.4 months. Notably, nearly a third of these patients (31.3%) had received prior therapy with the Bcl-2 inhibitor venetoclax.

About 23% of patients across the BEXMAB study were successfully bridged to a potentially curative stem cell transplant (SCT).

The most significant update is the new pharmacodynamic data that provided a clear biological explanation for the strong clinical results. The analysis showed a statistically significant correlation (p=0.0006) between deeper engagement of the Clever-1 target in the bone marrow and a positive clinical response. This correlation was particularly striking in the subgroup of treatment-naïve patients with <5% bone marrow blasts at baseline (38% of the cohort), a population for which effective, non-intensive therapies are urgently needed. In these patients, deeper target engagement translated to a 100% ORR, supporting bexmarilimab’s unique mechanism of action as a truly disease modifying agent, differentiating it from other investigational HR-MDS therapies, such as Bcl-2 inhibitors. For patients with a higher blast count (>5% at baseline), the ORR remained high at 75%.

With the result of this data, Faron is preparing for the next stage of development. Following guidance from the FDA announced on 18 August 2025, the Company has begun preparations for the dose-optimization stage of its Phase II/III trial for bexmarilimab, after which the trial will transition into the registrational stage with accelerated approval possibility. The combination therapy continues to be well-tolerated, with a safety profile similar, or even better to, azacitidine monotherapy. Only 36% of treatment-emergent adverse events were considered related to bexmarilimab, with no Grade 5 events.

Dr. Mika Kontro, MD, PhD, Associate Professor at University of Helsinki and Helsinki University Hospital Comprehensive Cancer Center, Department of Hematology said, “The BEXMAB data are encouraging, and the new biomarker analysis provides a clear pharmacodynamic rationale for bexmarilimab’s clinical activity. The direct correlation between how deeply we engage the Clever-1 target in the bone marrow and a patient’s clinical response reinforces the drug’s mechanism. The 100% ORR in patients with low blast counts suggest that this therapy may help in a population where current investigational treatments, including Bcl-2 inhibitors, have significant limitations.”

Dr. Maija Hollmén, PhD, Chief Scientific Officer of Faron Pharmaceuticals, added, “The selection of this BEXMAB data for an oral presentation at ESMO is a significant external validation of our science and the clinical potential of bexmarilimab. These findings help us understand why the drug works and for whom it works best. The clear biomarker impact in the bone marrow and unique efficacy in patients with low blast counts highlights Bex’s ability to change the course of the disease and provides a solid foundation for our late-stage clinical development, bringing this promising therapy to patients who desperately need better options.”

To register for the event visit: ESMO 2025. The details of the ESMO oral presentation are as follows:

Presentation title: Macrophage reprogrammer Bexmarilimab Plus Azacitidine in Myelodysplastic Syndrome: PK/PD and biomarker results from the Phase I/II BEXMAB Study

Presented by: Dr. Mika Kontro

Session type and title: Mini Oral Session: Haematological Malignancies

Room: Solingen Auditorium - Hall 23

Session date & time: Oct 19, 2025 (9:31 to 9:36 am CEST)

Abstract no.: 1249MO

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