How Does TYK2 March To Its Own Drummer?

In this episode of Derms and Conditions, host James Del Rosso, DO, is joined by Jason Hawkes, MD, a dermatologist and investigator at the Medical Research Center of Oregon, to discuss tyrosine kinase 2 (TYK2) inhibitors, particularly deucravacitinib, for plaque psoriasis. They explain how deucravacitinib, which targets the TYK2 pathway, differs from other JAK inhibitors by avoiding the "off-target" effects associated with JAK 1, 2, and 3 inhibitors, offering a more selective and safe treatment option. They begin by discussing the JAK-STAT pathway, with Dr Hawkes noting that while the science behind it was well known, TYK2's role in psoriasis took time to fully understand. TYK2 regulates key cytokines like IL-12, IL-23, and type 1 interferons, which are critical in psoriasis and psoriatic arthritis. Its more focused role within the immune response reduces the risk of systemic side effects compared to broader-acting JAK inhibitors. They also explore deucravacitinib’s selectivity, which targets the pseudokinase domain of TYK2, offering greater precision compared to inhibitors that target the ATP-binding domain shared by other JAKs. This selectivity results in deucravacitinib’s cleaner safety profile, reflected in the lack of a boxed warning and minimal monitoring requirements. Finally, they review long-term data, noting deucravacitinib's superior efficacy to apremilast and a stable safety profile over four years. While some safety signals, like herpetic infections, slightly increased over time, most adverse events were stable or decreased. They conclude by discussing the importance of personalized treatment decisions, emphasizing deucravacitinib’s advantages for patients who prefer oral medications and want to avoid injections. Tune in to the full episode for a comprehensive discussion on the clinical relevance of TYK2 inhibitors and the role of deucravacitinib in the psoriasis treatment landscape.