BE Study in Patients - Methotrexate Tablets

To characterize the pharmacokinetic profile of the Test product - Methotrexate Tablets USP, 2.5 mg of Amneal Pharmaceuticals, compared to that of the corresponding Reference product - Methotrexate Tablets USP 2.5 mg manufactured for DAVA Pharmaceuticals, Inc. in patients with mild to severe psoriasis or rheumatoid arthritis, who are already on established regimens of 2.5 mg every 12 hours for three doses per week under fasting conditions, and to assess their bioequivalence.

Patients will continue their own established dose of 2.5 mg tablet at 12 hours intervals for 3 doses given as a course once weekly. This dosing regimen will be kept constant throughout the study period. On day 0 of each period, the patient will be hospitalized/ housed in the clinical facility/hospital, so patient will be administered IP dose on day 1 under supervision of trained study staff. In supervised dosing, patient will be administered oral dose of Methotrexate Tablet 2.5 mg (Test or Reference product as per randomization schedule) with approximately 240 mL of water at ambient temperature in sitting position. Mouth check will be done by investigator/ designee followed by IP administration to verify dosing compliance. The patient will be advised to take two subsequent doses of the locally approved drug at every 12 hours of interval after the administration of study drug on day 1. Compliance to subsequent two doses of locally approved Methotrexate tablets 2.5 mg will be ensured as below in each period. The dose which is to be given 12 hours after IP administration (Second dose) will be administered inside clinical facility after collection of 12 hours post-dose PK sample under supervision of trained study personnel. The next dose (third dose) will be provided to the patients with the instruction to take the same on their own. Telephonic follow-up will be made on the next day for this third dose. The same will be documented in the patient dosing log. In period I, patient will be housed on day 0 at least 12 hours prior to IP dosing scheduled on day 1 and will remain in clinical facility till last PK sample on day 1. Patient will be checked out on day 1 after last PK blood sample collection followed by administration of second dose of locally approved Methotrexate 2.5 mg tablet. The third dose of locally approved Methotrexate 2.5 mg tablet should be taken by patient on their own approximately 12 hours after the second dose. The same procedure will be followed in period II. There will be a period of at least 7 days between first dosing (IP administration) in both the study periods. The patients will have to stay hospitalized for a period of 2 days and 1 night in each study period for their convenience and close safety monitoring.