Subcutaneous (SC) methotrexate (MTX) offers higher efficacy, faster results, fewer adverse effects, and lower relapse rates than oral MTX in treatment of chronic plaque psoriasis, according to study results published in Dermatologic Therapy.
Researchers evaluated the effects of oral MTX vs SC MTX for treatment and prophylaxis of chronic plaque psoriasis in 28 adults. Patients were divided into two groups of 14. Group 1 received a weekly dose of oral MTX for 12 weeks. The starting dose was 7.5 mg, which researchers increased by 2.5 mg/mo until each patient received 12.5-15 mg/wk.
Group 2 received a weekly dose of SC MTX for 12 weeks. Patients with mild and moderate cases of chronic plaque psoriasis received a starting dose of 7.5 mg whereas patients with severe cases received a starting dose of 10 mg. Doses were increased by 2.5 mg/mo until each patient received 10-15 mg/wk.
Researchers calculated the psoriasis area and severity index (PASI) score for every patient at baseline, every 2 weeks during the first month, and every 4 weeks during the following 2 months. They evaluated response to treatment by a reduction in PASI score and photographic comparison at these same intervals.
Results revealed that 57.1% of group 2 patients experienced a reduction in PASI score by 90% compared with 7.1% of group 1 patients. Group 1 patients showed a mean reduction in PASI score from 20±7.4 before treatment to 11.2±6.3 after treatment with high statistically significant difference (P <.001). Group 2 patients showed a reduction in PASI score from 23.4±14.7 before treatment to 2.6±2.6 after treatment (P <.001).
When comparing the efficacy and tolerability of oral MTX vs SC MTX in this study, there was a greater reduction in patients who received SC MTX (P <.001). Clinical improvement was higher in group 2 with significant difference (P <.007). Also, there was a significant difference between both groups (P <.05) with regard to adverse effects. Group 1 experienced higher rates of adverse effects than group 2, including fatigue (42.9% vs 28.6%), gastrointestinal upset (71.4% vs 14.3%), and liver enzymes (21.3% vs 7.1%).
The study researchers concluded that in chronic plaque psoriasis, SC MTX has higher efficacy and produces faster results and more tolerability with fewer adverse effects and lower relapse rates when compared with oral MTX given in the same doses for the same duration. They recommended further research to determine the cost efficacy of both options.
Attwa EM, Elkot RA, Abdelshafey AS, Hafez AR. Subcutaneous methotrexate versus oral form for treatment and prophylaxis of chronic plaque psoriasis. Dermatol Ther. 2019:e13051.