Crisaborole is a topical phosphodiesterase 4 (PDE4) inhibitor used for the treatment of mild to moderate atopic dermatitis (eczema) in adults and children. It works by inhibiting PDE4, an enzyme that degrades cyclic AMP (cAMP), leading to reduced production of pro-inflammatory cytokines. This helps relieve itching, redness, and inflammation associated with eczema.
Crisaborole is formulated as a 2% ointment and is applied topically to the affected skin areas.
Indications include:
∙ Mild to moderate atopic dermatitis in patients 3 months of age and older
∙ Investigational use in psoriasis and other inflammatory skin conditions
Impurities in crisaborole arise from its multi-step chemical synthesis, particularly involving boronic acid chemistry, aromatic substitution, and amide bond formation, as well as from degradation due to hydrolysis or oxidation. Since it is used topically in sensitive skin areas, impurity levels must be tightly controlled as per ICH Q3A/B, USP, and dermatological product regulations.
Process-Related Impurities
Degradation Impurities
Elemental Impurities
Analytical Techniques for Impurity Detection
Photostability and hydrolysis stress testing – required for topical stability studies
Crisaborole is used to treat mild to moderate atopic dermatitis (eczema) by reducing inflammation and itch when applied to the skin.
It inhibits PDE4, increasing cAMP levels in skin cells and thereby reducing pro-inflammatory cytokine production, such as TNF-α, IL-4, and IL-13.
No. Crisaborole is a non-steroidal anti-inflammatory ointment, making it suitable for long-term use, even on sensitive skin areas.
Yes, but it should be stored at controlled room temperature, protected from excessive moisture and heat. The boronic acid group is sensitive to oxidation and hydrolysis, so the formulation is stabilized accordingly.
