Natrunix or Placebo in Combination With Methotrexate in Rheumatoid Arthritis

Potential subjects will be consented and screened for study eligibility and the enrolled will be randomized in a 1:1:1 ratio to receive either: 200 mg Natrunix; 400mg Natrunix; or placebo. All subjects will enter the study on stable MTX dose. Subjects will receive once weekly injection of Natrunix or placebo in addition to MTX for 12 weeks. The study will conclude after 13 weeks. Study Duration is 17 weeks (4-week maximum screening + 12-week treatment period = 1-week follow-up. The primary objective is to determine the ACR 20 response rate in subjects receiving stable dose of MTX and after 12 weeks of treatment with either Natrunix or placebo. The study will also examine what impact the addition of Natrunix or placebo has on the scores of various rheumatological grading scales, including ACR 50, NRS-pain score, and 66/68-joint count, as well as safety. All subjects enrolled in the study will be taking concomitant methotrexate.