How to distinguish and define drug patents?

There is no special classification and definition. I divide it like this:

Patents in China are divided into three categories, namely, inventions, utility models and designs. Drugs are basically applied for invention patents, which are divided into:

1, product invention, including new compounds, compositions, biological products, etc.

2. Method invention, including production process, synthesis method and detection method.

3, the purpose of the invention, generally refers to the new indications.