For Healthcare Professionals

REGN7257 in Adult Patients With Severe Aplastic Anemia That Is Refractory to or Relapsed on Immunosuppressive Therapy


About the study

The primary objective of this study is to assess the safety and tolerability of REGN7257 in patients with immunosuppressive therapy (IST)-refractory or IST-relapsed severe aplastic anemia (SAA). An additional primary objective (for Part B only) is to evaluate the clinical efficacy of REGN7257 in patients with IST-refractory or IST-relapsed SAA. The secondary objectives of this study are to assess the following for REGN7257: Clinical response over time Maintenance of response Impact on transfusion requirements Effect on blood counts and cell populations Pharmacokinetics (PK) Immunogenicity

Who can take part

You may be eligible to participate in the study if you meet the following criteria:


Key Inclusion Criteria:

  1. SAA that is IST-refractory or IST-relapsed, as defined in the protocol
  2. Hematopoietic stem cell transplantation (HSCT) is not available or suitable as a treatment option or has been refused by the patient
  3. Adequate hepatic and renal function as defined in the protocol


Key Exclusion Criteria:

  1. Diagnosis of Fanconi anemia or other congenital bone marrow failure syndrome as defined in the protocol
  2. Evidence of myelodysplastic syndrome as defined in the protocol
  3. Paroxysmal nocturnal hemoglobinuria (PNH) with evidence of clinically significant hemolysis (eg, treatment indicated) or history of PNH-associated thrombosis
  4. Treatment with a T cell-depleting agent (eg, ATG or alemtuzumab) within 6 months prior to dosing
  5. Treatment with a calcineurin inhibitor (eg, cyclosporine) within 4 weeks prior to dosing as defined in the protocol
  6. Treatment with eltrombopag or investigational thrombopoietin receptor agonist, Granulocyte Colony-Stimulating Factor (G-CSF), or an androgen (eg, danazol), within 2 weeks prior to dosing
  7. HIV, hepatitis B or hepatitis C positive by serological testing at the screening visit as defined in the protocol
  8. Active tuberculosis, latent tuberculosis infection (LTBI) or history incompletely-treated tuberculosis or LTBI
  9. Active infection as defined in the protocol including COVID-19

Note: Other protocol-defined inclusion/ exclusion criteria apply

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Study Locations

Enter your ZIP code/Postal code/PIN code to locate study sites near you:

How to Apply

Contact the study center to learn if this study is a good match for you.
Phone iconCall 844-734-6643Email iconEmail Study Center

Study’s details


Severe Aplastic Anemia (SAA)

Age (in years)



Phase 1/Phase 2

Participants needed


Est. Completion Date

Jan 2, 2026

Treatment type



Regeneron Pharmaceuticals identifier


Study number


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