anti c fms monoclonal antibody amg 820

Drug Overview

The medication known as anti c fms monoclonal antibody amg 820 (also identified as MEDI7247) is an investigational, high-precision cancer therapy designed to treat aggressive blood cancers and solid tumors. It is a “first-in-class” Antibody-Drug Conjugate (ADC) that targets the metabolic “engine” of cancer cells.

Developed by AstraZeneca/MedImmune, MEDI7247 acts like a biological guided missile. It is engineered to seek out and bind to a protein called ASCT2 (also known as SLC1A5), a transporter that cancer cells use to “gobble up” glutamine—a primary fuel source for rapid tumor growth. By targeting this specific metabolic door, MEDI7247 delivers a lethal chemical payload directly into the cancer cell while attempting to spare healthy tissues.

• Generic Name: Anti-ASCT2 antibody-drug conjugate MEDI7247.
• Drug Class: Antibody-Drug Conjugate (ADC) / DNA-alkylating agent.
• Target: ASCT2 (Alanine, Serine, Cysteine-preferring Transporter 2 / SLC1A5).
• Route of Administration: Intravenous (IV) infusion.
• FDA Approval Status: Investigational/Discontinued. As of March 2026, MEDI7247 has been discontinued from clinical development following Phase I trials. While it remains a significant subject of scientific study for its unique mechanism, it is not currently FDA-approved for clinical use.

What Is It and How Does It Work? (Mechanism of Action)

The ASCT2 Target

Many cancers are “glutamine addicted.” They overexpress ASCT2, a transport protein on the cell surface that pumps glutamine into the cell to support rapid division and energy production. ASCT2 is found in high levels in many leukemias, multiple myeloma, and various solid tumors (such as lung and colorectal cancers).

Molecular Level Mechanisms

1. Selective Binding: After infusion, the monoclonal antibody portion of MEDI7247 circulates until it finds cells displaying the ASCT2 transporter. It binds to this protein with high affinity.
2. Internalization: Once attached, the cancer cell pulls the ADC inside through a process called endocytosis.
3. Payload Release: Inside the cell’s lysosomes, the chemical linker is broken down, releasing a highly potent payload called pyrrolobenzodiazepine (PBD).
4. DNA Cross-linking: PBD is a DNA-alkylating agent. It binds specifically to the minor groove of the cancer cell’s DNA and forms cross-links. This “handcuffs” the DNA, preventing the cell from unzipping its genetic code to replicate or repair itself.
5. Cell Death: The irreversible DNA damage triggers apoptosis (programmed cell death). Because ASCT2 is the target, the drug kills the cell not just by damaging its DNA, but by specifically targeting the cells that are most metabolically active.

FDA Approved Clinical Indications

There are currently no FDA-approved indications for MEDI7247.

During its clinical life, it was investigated in Phase I trials (such as NCT03106428) for the following conditions:

• Relapsed or Refractory Hematologic Malignancies: Including Acute Myeloid Leukemia (AML) and Diffuse Large B-Cell Lymphoma (DLBCL).
• Multiple Myeloma: For patients who had failed multiple lines of standard therapy.
• Advanced Solid Tumors: Investigating its effectiveness in cancers that heavily overexpress the ASCT2 transporter.

Dosage and Administration Protocols

Because this agent was discontinued during Phase I, there is no established “standard” dose for clinical practice. The following protocols were utilized during dose-escalation research.

Clinical Efficacy and Research Results

The clinical journey of MEDI7247 provided critical data on the feasibility of targeting cancer metabolism via ADCs.

• Targeting Success: Preclinical studies showed that MEDI7247 was highly effective at killing AML cells in laboratory models, particularly those with high ASCT2 expression.
• Phase I Challenges: While the drug successfully targeted ASCT2, Phase I human trials revealed challenges regarding the “therapeutic window”—the balance between a dose high enough to kill cancer and low enough to be safe for the patient.
• Legacy of PBD Payloads: The data from MEDI7247 has helped researchers refine the use of PBD payloads (the DNA-killer) in newer ADCs to ensure they are less toxic to healthy blood-forming stem cells.

Safety Profile and Side Effects

The primary reason for the discontinuation of many PBD-based ADCs like MEDI7247 relates to their impact on healthy tissues that also express the target or are sensitive to DNA damage.

Common Side Effects (>10%):

• Fatigue: A general sense of tiredness common with DNA-damaging therapies.
• Nausea/Vomiting: Usually mild and manageable with anti-emetics.
• Anemia: A drop in red blood cell counts.

Serious Adverse Events (Dose-Limiting):

• Hematologic Toxicity: Significant drops in white blood cells (neutropenia) and platelets (thrombocytopenia), as bone marrow can be sensitive to PBD payloads.
• Edema/Effusions: Swelling in the limbs or fluid buildup around the lungs or heart (a known side effect of the PBD class).
• Hepatotoxicity: Elevation of liver enzymes, requiring careful monitoring.

Research Areas

In the field of Stem Cell and Regenerative Medicine, ASCT2 is a protein of high interest because it plays a role in the “metabolic reprogramming” of stem cells. Researchers are studying how blocking ASCT2 affects Mesenchymal Stem Cells (MSCs). By understanding the data from MEDI7247, scientists are learning how to selectively target “malignant” stem cells (cancer stem cells) while sparing “healthy” regenerative stem cells, which is the holy grail of precision oncology.

Patient Management and Practical Recommendations

Pre-treatment Tests (Historically Required):

• ASCT2 Expression Profiling: Biopsies to confirm high levels of the transporter protein.
• Complete Blood Count (CBC): Essential to ensure the bone marrow can handle the treatment.
• Baseline Imaging: To track tumor size and monitor for pre-existing fluid buildup (effusions).

Precautions:

• Fluid Monitoring: Patients on PBD-class drugs must be closely monitored for sudden weight gain or shortness of breath (signs of edema).
• Sun Protection: Some PBD-based drugs can cause skin sensitivity to light.

“Do’s and Don’ts” List:

• DO report any unusual bruising or bleeding immediately (signs of low platelets).
• DO maintain high nutritional intake, as the drug targets a protein involved in nutrient transport.
• DON’T ignore a fever over 100.4°F (38°C), as this is a medical emergency in patients with low white blood cell counts.
• DON’T start any new medications without consulting your oncology team, as they may interact with liver metabolism.

Legal Disclaimer

The information provided in this guide is for educational and informational purposes only and does not constitute medical advice. MEDI7247 is an investigational agent that has been discontinued from clinical development. It is not approved by the US Food and Drug Administration (FDA) for any indication. Always consult with a qualified oncologist regarding currently available and approved treatments for your specific condition.