Pfizer Inc. (NYSE:PFE) announced today top-line results from ORAL Start (A3921069), a Phase 3 study of the investigational agent tofacitinib, a novel, oral Janus kinase (JAK) inhibitor for the treatment of adults with moderate-to-severe active rheumatoid arthritis (RA). ORAL Start, an ongoing two-year study in methotrexate (MTX)-naïve patients with moderate-to-severe active RA, randomized to receive tofacitinib 5 or 10 mg twice-daily (BID) as monotherapy or MTX, met its primary endpoints at both the 5 and 10 mg BID doses. Tofacitinib was found to be superior to MTX with statistically significant changes shown in inhibiting structural damage, as measured by change from baseline in modified Total Sharp Score (mTSS), and in reducing signs and symptoms of RA, as measured by ACR70 response rates. Both primary endpoints assessed tofacitinib versus MTX at six months. The data reported are from a planned analysis at one year. No new safety signals emerged in the ORAL Start study, and the safety profile of tofacitinib remained consistent with that seen previously in the clinical development program. Safety findings observed in the overall tofacitinib RA program include serious and other important infections, including tuberculosis and herpes zoster; malignancies, including lymphoma; decreased neutrophil counts and neutropenia; and lipid elevations. A detailed analysis of the ORAL Start findings will be submitted to a future scientific meeting. Pfizer also noted today during its second quarter earnings call that the U.S. Food and Drug Administration (FDA) has recently requested additional analysis of the existing data in the tofacitinib New Drug Application (NDA). Pfizer is planning to provide FDA with this information in early August and, given this timing, it anticipates that FDA may require additional time beyond the August 21 Prescription Drug User Fee Act (PDUFA) date to review the information. About ORAL Start ORAL Start is an ongoing two-year study that randomized 958 patients with moderate-to-severe active RA who were naïve to MTX to receive tofacitinib monotherapy 5 or 10 mg BID or MTX. The primary objectives of ORAL Start are to compare preservation of joint structure, treatment of signs and symptoms and safety and tolerability with tofacitinib 5 or 10 mg BID versus MTX. Results are from a planned 12-month interim analysis.