APIs can be divided into the following categories based on their source and patent status:
Chemically synthesized APIs: These APIs are obtained through chemical reactions or synthesis and are commonly used in traditional small molecule drugs. Specifically, they include antibiotics (such as amoxicillin, erythromycin), antiviral drugs (such as lamivudine, oseltamivir), analgesics (such as ibuprofen, acetaminophen), antihypertensive drugs (such as amlodipine, valsartan), hypoglycemic drugs (such as metformin, gliclazide), etc.
Biotechnology APIs: They are produced through biotechnology (such as genetic engineering, fermentation, etc.) and are usually used in biological products and macromolecule drugs. These APIs include monoclonal antibodies (such as trastuzumab, bevacizumab), recombinant proteins (such as recombinant human insulin, erythropoietin), vaccine components (such as active ingredients of human papillomavirus vaccines), growth factors (such as recombinant human growth hormone), etc.
Naturally extracted APIs: Active ingredients extracted from natural sources, including extracts of animals, plants, minerals, etc. Specific examples include plant extracts (such as paclitaxel, atropine), animal extracts (such as heparin, protamine), mineral extracts (such as calcium carbonate, zinc oxide), etc.
Radioactive APIs: contain radioactive ingredients and are used for medical imaging diagnosis or radiotherapy. For example, diagnostic radiopharmaceuticals such as technetium-99m, etc.