Niosomal methotrexate gel in the treatment of localized psoriasis: Phase I and phase II studies

Background: Efficacy of topical methotrexate in psoriasis is limited by its penetration.
Aims: The study involved the preparation of niosomal methotrexate in chitosan gel and to test the same for irritation and sensitization on healthy human volunteers followed by assessing the efficacy of the gel through double-blind placebo-controlled study on psoriasis patients and also comparing its efficacy with a marketed methotrexate gel.
Methods: The methotrexate niosomes were prepared by lipid layer hydration method. The characterized niosomes were incorporated in chitosan gel. The gels were tested on 10 human volunteers to check for irritation and skin sensitivity by human repeated insult patch test (HRIPT). The formulations were assessed for efficacy by double-blind placebo-controlled study in 10 psoriasis patients for each formulation. The efficacy was calculated by psoriasis area and severity index scoring method. The global score was used to assess the progress of the disease.
Results: The HRIPT test did not produce any significant irritation or sensitization on healthy human volunteers. The placebo and marketed gels were compared with niosomal methotrexate gel. At Week 12, with niosomal methotrexate gel, there was reduction in total score from 6.2378±1.4857 to 2.0023±0.1371.
Conclusion: These results suggest that niosomal methotrexate gel is more efficacious than placebo and marketed methotrexate gel.

Keywords
Human repeated insult patch test (HRIPT), Niosomal methotrexate gel, Psoriasis area and severity index (PASI)