Figotinib belongs to the category of several generations of targeted drugs

Filgotinib(Filgotinib) is classified as a representative drug among the new generation of JAK inhibitors and is generally regarded as the "second generation" JAK targeting drug. In the development process of JAK family targeted drugs, significant progress has been made in enhancing selectivity and reducing side effects from the first generation to the second generation. The first-generation JAK inhibitors (such as tofacitinib) have multi-target characteristics and may inhibit multiple pathways such as JAK1, JAK2, and JAK3 at the same time. Although the efficacy is obvious, the side effects are more prominent, such as increased risk of infection, elevated blood lipids, and risk of cardiovascular events.

As a second-generation JAK inhibitor, filgotinib’s outstanding feature is its highly selective targeting of the JAK1 pathway. JAK1 is an important molecule that regulates the signaling of multiple pro-inflammatory cytokines (such as IL-6, IL-2, IFN, etc.) and is involved in the core pathogenesis of autoimmune diseases. By precisely inhibiting JAK1, filgotinib can effectively control the inflammatory response and relatively reduce the adverse effects on the hematopoietic system and natural immune system. The optimization of this target makes it have a better safety profile and is especially suitable for long-term chronic disease management.

In the development system of targeted drugs, "Second generation" often means that the mechanism is clearer and the side effects are more controllable, and filgotinib is a typical example. Its selective inhibition mechanism also makes it different from early non-selective JAK inhibitors, and is expected to reduce the long-term complications caused by deep immunosuppression. Therefore, the industry generally classifies filgotinib as a second-generation targeted drug. Its design concept is in line with the current development direction of precision medicine, which is to pursue better tolerability and lower systemic side effects on the basis of ensuring efficacy.

Although currently "generational division" among JAK inhibitors has not been as strictly standardized as EGFR and ALK inhibitors, from the perspective of drug selectivity and safety, filgotinib does represent the direction of a new generation of JAK-targeted drugs. Its development concept focuses on improving the safety margin of long-term use for patients and achieving maximum therapeutic benefit through precise regulation of specific inflammatory pathways.

Reference materials:https://go.drugbank.com/drugs/DB14845