Is baricitinib/alemin a biologic drug?

Baricitinib (Baricitinib) is a JAK inhibitor drug that is widely used in the treatment of diseases such as rheumatoid arthritis, alopecia areata, and COVID-19. Although it plays an important role in the treatment of immune system diseases, many people often mistakenly classify it as a biologic drug. In fact, baricitinib is not a biological agent in the traditional sense.

Biological agents usually refer to drugs produced through biotechnological means, such as recombinantDNA technology, genetic engineering, etc., and are mainly used to regulate the function of the immune system. Biological agents include monoclonal antibodies, recombinant proteins, vaccines, etc., which are usually produced by living cells and have relatively complex molecular structures. For example, tumor necrosis factor (TNF) inhibitors (such as infliximab, adalimumab) and IL-6 inhibitors (such as tocilizumab) are biological agents.

Different from these traditional biologics, baricitinib is a small molecule targeted drug. It regulates immune responses and alleviates diseases caused by the immune system by inhibiting Janus kinase (JAK). JAK is an intracellular enzyme involved in cytokine signal transduction, and baricitinib blocks the transmission of these signals by inhibiting the JAK enzyme, thereby reducing the excessive response of the immune system.

The manufacturing process for baricitinib is different from biologics. Biologics are typically manufactured through cell culture and extraction processes, whereas baricitinib is synthesized through chemical synthesis. This makes baricitinib a small molecule drug that is fundamentally different from traditional biological agents in terms of production method, structure and mechanism.

Although the clinical effects of baricitinib are similar to those of some biological agents and involve the regulation of the immune system, it is essentially a small molecule drug rather than a biological agent. Small molecule drugs usually have smaller molecular weights, can be taken orally, and have simpler drug structures. In contrast, biologics usually require injection and have more complex molecular structures, usually composed of biological macromolecules (such as proteins).

Reference materials:https://www.ncbi.nlm.nih.gov/books/NBK572064/