Astellas pharma us inc, Dr reddys laboratories ltd, Sandoz inc, Watson laboratories inc, Astellas Pharma US • Immediate-release formulations of tacrolimus are indicated for the prophylaxis of organ rejection in adult and pediatric patients receiving allogeneic liver, kidney, heart, or lung transplants, in combination with other immunosuppressants. Extended-release formulations of tacrolimus are indicated for the prophylaxis of organ rejection in adult and pediatric patients receiving kidney transplants, in combination with other immunosuppressants, and may be used in patients converted from immediate-release formulations. Topical tacrolimus ointment is indicated as second-line therapy for short-term and non-continuous treatment of moderate-to-severe atopic dermatitis in non-immunocompromised adults and children who have failed to respond adequately to other topical treatments or for whom alternative treatments are not advisable. Both available strengths are indicated in adult patients, while only the lower strength (0.03%) formulation is indicated in pediatric patients between 2 and 15 years of age.
Tacrolimus is a calcineurin inhibitor used to prevent organ transplant rejection and to treat moderate to severe atopic dermatitis.
The mechanism of action of tacrolimus in atopic dermatitis is not known. While the following have been observed, the clinical significance of these observations in atopic dermatitis is not known. It has been demonstrated that tacrolimus inhibits T-lymphocyte activation by first binding to an intracellular protein, FKBP-12. A complex of tacrolimus-FKBP-12, calcium, calmodulin, and calcineurin is then formed and the phosphatase activity of calcineurin is inhibited. This prevents the dephosphorylation and translocation of nuclear factor of activated T-cells (NF-AT), a nuclear component thought to initiate gene transcription for the formation of lymphokines. Tacrolimus also inhibits the transcription for genes which encode IL-3, IL-4, IL-5, GM-CSF, and TNF-, all of which are involved in the early stages of T-cell activation. Additionally, tacrolimus has been shown to inhibit the release of pre-formed mediators from skin mast cells and basophils, and to downregulate the expression of FceRI on Langerhans cells.
