Open-Label, Multicenter Extension Study for Patients Completing Treatment Phase of a Rigel-Sponsored R935788 Studies

Inclusion Criteria: * Patients must give written informed consent by signing an IRB/EC-approved Informed Consent Form (ICF) prior to admission to this study * Patients who are being treated in Study C-788-006X * Patients who completed Studies C-788-010 or C-788-011 and did not withdraw due to adverse events * Patients who withdrew from Study C-788-010 at Month 4 or Month 5 because of a pre-defined lack of efficacy * Females of childbearing potential must be fully informed of the potential for R788 to adversely affect the fetus and, if sexually active, must agree to use a well established method of birth control during the study (oral contraceptive, mechanical barrier, long acting hormonal agent). These patients must not be lactating and must have a negative pregnancy test at the time of entry and at each laboratory determination. Exclusion Criteria: * The patient has a history of, or a concurrent, clinically significant illness, medical condition (other than arthritis) or laboratory abnormality that, in the Investigator's opinion, could affect the conduct of the study. Specifically, excluded are patients with the following: 1. unresolved Grade 2 or greater toxicity in a RA protocol studying R788 2. uncontrolled or poorly controlled hypertension; 3. recent (within past 2 months) serious surgery or infectious disease; 4. recent history (since enrollment in prior R788 study) of, or treatment for, a malignancy other than non-melanomatous skin cancer, or any history of lymphoma; 5. known to be positive for Hepatitis B, Hepatitis C, HIV or Tuberculosis; 6. interstitial pneumonitis or active pulmonary infection; 7. known laboratory abnormalities: ALT \> 1.2 x ULN, creatinine \>1.5x ULN, an ANC \<2,500/mm3 or 2.5 x 109/L, lymphocyte count \< 600/mm3 or 0.6 x 109L, Hgb \< 9 g/dL or 5 mmol/L, platelet count \<125,000/mm3 or 125 x 109/L are excluded. * The patient has a history of substance abuse, drug addiction or alcoholism. Patients may consume up to 4 units of alcohol per week; however, alcohol should be avoided in the 72 hours prior to lab assessments. Patients who cannot reliably comply with this should be excluded. A unit of alcohol is defined as the following: Beer = 12 oz or 355 mL; wine = 5 oz or 148 mL; sweet dessert wine = 3 oz or 89 mL; 80 proof distilled spirits = 1.5 oz or 44 mL. * The patient is unable to report for clinical and laboratory monitoring as per protocol.