The field of monoclonal antibodies (mAbs) has seen explosive growth over the last four decades, transforming from a novel scientific concept into a cornerstone of modern therapy. The number of FDA approved monoclonal antibodies and antibody-related products has grown from a single approval in 1986 to over 160 in mid-2024, with the count continuing to rise. With new formats like antibody-drug conjugates (ADCs) and bispecific antibodies constantly reaching the market, the exact figure is a moving target. The FDA's Purple Book database serves as the official registry for these licensed biological products, reflecting the latest additions.
A Rapidly Growing Class of Biologics
Following the first FDA approval for muromonab-CD3 in 1986, the pace of mAb approvals has accelerated significantly, particularly in recent years. For instance, the number of approved products took 29 years to reach 50 (in 2015) but only six more years to reach 100 (in 2021). By the end of 2024, sources reported a total of 159 antibody-based biologics, and by August 2025, over 14 multispecific antibodies alone had been approved. This rapid expansion is fueled by advances in biotechnology and a deeper understanding of disease mechanisms, allowing for the development of more sophisticated and effective therapies.
The Evolution of Monoclonal Antibody Development
First-Generation vs. Modern mAbs
Early mAbs, like the murine-derived muromonab-CD3, were plagued by high immunogenicity and short half-lives in humans, which often led to treatment failure. This spurred the development of more advanced generations of antibodies:
- Chimeric antibodies: Part mouse, part human, to reduce immunogenicity.
- Humanized antibodies: Mostly human, with mouse-derived antigen-binding regions, further reducing the immune response.
- Fully human antibodies: Engineered using technologies like phage display or transgenic mice, representing the current standard for minimal immunogenicity.
Advanced Antibody Formats
Beyond simply reducing immunogenicity, modern mAbs have been engineered to perform more complex functions, leading to new classes of therapeutics:
- Antibody-drug conjugates (ADCs): These combine a mAb's precise targeting ability with a cytotoxic payload (a chemotherapy-like drug). The antibody delivers the drug directly to the target cells, sparing healthy tissue. As of April 2025, 14 ADC drugs had been approved.
- Bispecific antibodies: Designed to bind to two different targets simultaneously, such as a cancer cell and an immune cell, effectively bridging the two for a targeted immune response. These are becoming a major focus for oncology and other applications.
Key Therapeutic Areas Treated with Monoclonal Antibodies
Monoclonal antibodies are a versatile tool used across a wide spectrum of diseases:
- Oncology: A major application for mAbs, which can mark cancer cells for destruction by the immune system, block growth signals, or act as checkpoint inhibitors to unleash a potent immune response against tumors. Examples include pembrolizumab (Keytruda) and nivolumab (Opdivo).
- Autoimmune Diseases: By targeting specific inflammatory molecules or immune cells, mAbs help manage conditions like rheumatoid arthritis, multiple sclerosis, and Crohn's disease. Examples include adalimumab (Humira) and infliximab (Remicade).
- Infectious Diseases: The COVID-19 pandemic highlighted the role of mAbs in neutralizing viruses. They are also used for other infectious diseases like RSV prevention.
- Other Conditions: The applications continue to diversify, including treatments for high cholesterol (evolocumab, Repatha), osteoporosis (denosumab, Prolia), and eye conditions like macular degeneration (ranibizumab, Lucentis).
Recent FDA Approved Monoclonal Antibodies (2025)
Several mAbs and related biologics received FDA approval in 2025, further illustrating the ongoing innovation:
- Datopotamab deruxtecan (Datroway): An ADC approved in January 2025 for unresectable or metastatic HR-positive, HER2-negative breast cancer.
- Nipocalimab-aahu (Imaavy): A monospecific antibody approved in April 2025 to treat generalized myasthenia gravis.
- Telisotuzumab vedotin-tllv (Emrelis): An ADC approved in May 2025 for non-squamous non-small cell lung cancer with high c-Met protein overexpression.
- Clesrovimab-cfor (Enflonsia): A mAb approved in June 2025 to prevent RSV lower respiratory tract disease in neonates and infants.
- Linvoseltamab-gcpt (Lynozyfic): A bispecific mAb approved in July 2025 for relapsed or refractory multiple myeloma.
Monoclonal Antibodies vs. Other Biologics
This table highlights key differences between mAbs and other common biologics.
| Feature | Monoclonal Antibodies | Other Biologics (e.g., Cytokines, Recombinant Proteins) |
|---|---|---|
| Mechanism | Binds to a single, specific target (antigen) with high precision to trigger an immune response, block a protein, or deliver a payload. | Modulates broader biological pathways or replaces deficient proteins; may have more systemic effects. |
| Specificity | Extremely high specificity due to monoclonal nature, designed to target one protein on a specific cell type. | Specificity can vary. Some act on broad cell types, while others, like enzymes, have specific biochemical roles. |
| Production | Derived from cloned cells (hybridomas or other systems) and requires complex, specialized biomanufacturing processes. | Produced via recombinant DNA technology in host cells (bacteria, yeast, mammalian cells); manufacturing depends on the protein. |
| Immunogenicity | Varies by origin (mouse, chimeric, humanized, human); engineered to minimize immune reactions (anti-drug antibodies). | Can also be immunogenic, but this is highly dependent on the protein and its similarity to the endogenous human version. |
| Application | Cancer, autoimmune disorders, infectious diseases, neurological conditions, high cholesterol, etc. | Hormones (insulin), growth factors, vaccines, and enzymes. |
The Regulatory Landscape and Future Direction
The FDA, through the Center for Drug Evaluation and Research (CDER) and the Center for Biologics Evaluation and Research (CBER), regulates the development, testing, and approval of mAbs. The agency provides detailed guidance to ensure product quality, safety, and efficacy. Regulatory changes continue to evolve, such as the FDA's recent announcement to reduce animal testing for these biologics.
The future of mAbs is focused on pushing the boundaries of what these therapeutics can do. Next-generation products, including bispecific ADCs and fusion proteins, are currently in development. Furthermore, the market continues to expand globally and into new therapeutic areas, including neurological disorders and rare genetic conditions. As technology advances, the number of FDA approved monoclonal antibodies will only continue its upward trajectory, leading to even more precise and effective treatments for patients.
Conclusion
Since the first in 1986, the number of FDA approved monoclonal antibodies has grown dramatically, with well over 160 distinct entities now part of the therapeutic landscape. This increase is a testament to the versatility and precision of these biologic drugs, which have revolutionized treatment for a vast range of conditions, from cancer and autoimmune disorders to infectious diseases. As innovation continues with new formats like ADCs and bispecifics, this class of drugs is set to expand further, offering new hope and more effective treatments for patients worldwide. For the most up-to-date count, continuous reference to official FDA resources is necessary, as the number is always on the rise.
