Background & Aims: This study evaluated the efficacy and safety of adalimumab, a fully human, anti–tumor necrosis factor monoclonal antibody administered subcutaneously, in the maintenance of response and remission in patients with moderate to severe Crohn’s disease (CD). Methods: Patients received open-label induction therapy with adalimumab 80 mg (week 0) followed by 40 mg (week 2). At week 4, patients were stratified by response (decrease in Crohn’s Disease Activity Index ≥70 points from baseline) and randomized to double-blind treatment with placebo, adalimumab 40 mg every other week (eow), or adalimumab 40 mg weekly through week 56. Coprimary end points were the percentages of randomized responders who achieved clinical remission (Crohn’s Disease Activity Index score <150) at weeks 26 and 56. Results: The percentage of randomized responders in remission was significantly greater in the adalimumab 40-mg eow and 40-mg weekly groups versus placebo at week 26 (40%, 47%, and 17%, respectively; P < .001) and week 56 (36%, 41%, and 12%, respectively; P < .001). No significant differences in efficacy between adalimumab eow and weekly were observed. More patients receiving placebo discontinued treatment because of an adverse event (13.4%) than those receiving adalimumab (6.9% and 4.7% in the 40-mg eow and 40-mg weekly groups, respectively). Conclusions: Among patients who responded to adalimumab, both adalimumab eow and weekly were significantly more effective than placebo in maintaining remission in moderate to severe CD through 56 weeks. Adalimumab was well-tolerated, with a safety profile consistent with previous experience with the drug. Background & Aims: This study evaluated the efficacy and safety of adalimumab, a fully human, anti–tumor necrosis factor monoclonal antibody administered subcutaneously, in the maintenance of response and remission in patients with moderate to severe Crohn’s disease (CD). Methods: Patients received open-label induction therapy with adalimumab 80 mg (week 0) followed by 40 mg (week 2). At week 4, patients were stratified by response (decrease in Crohn’s Disease Activity Index ≥70 points from baseline) and randomized to double-blind treatment with placebo, adalimumab 40 mg every other week (eow), or adalimumab 40 mg weekly through week 56. Coprimary end points were the percentages of randomized responders who achieved clinical remission (Crohn’s Disease Activity Index score <150) at weeks 26 and 56. Results: The percentage of randomized responders in remission was significantly greater in the adalimumab 40-mg eow and 40-mg weekly groups versus placebo at week 26 (40%, 47%, and 17%, respectively; P < .001) and week 56 (36%, 41%, and 12%, respectively; P < .001). No significant differences in efficacy between adalimumab eow and weekly were observed. More patients receiving placebo discontinued treatment because of an adverse event (13.4%) than those receiving adalimumab (6.9% and 4.7% in the 40-mg eow and 40-mg weekly groups, respectively). Conclusions: Among patients who responded to adalimumab, both adalimumab eow and weekly were significantly more effective than placebo in maintaining remission in moderate to severe CD through 56 weeks. Adalimumab was well-tolerated, with a safety profile consistent with previous experience with the drug. See Turner D et al on page 103 for companion article in Clin Gastroenterol Hepatol.Tumor necrosis factor (TNF) is an important cytokine in the pathogenesis of Crohn’s disease (CD), with elevated concentrations playing a role in pathologic inflammation.1Papadakis K.A. Targan S.R. Tumor necrosis factor: biology and therapeutic inhibitors.Gastroenterology. 2000; 119: 1148-1157Abstract Full Text Full Text PDF Scopus (324) Google Scholar, 2Van Deventer S.J. Tumour necrosis factor and Crohn’s disease.Gut. 1997; 40: 443-448Google Scholar Clinical trials have demonstrated the efficacy of infliximab, a chimeric monoclonal antibody to TNF, for induction and maintenance therapy of patients with moderate to severe CD, including those with draining fistulas.3Hanauer S.B. Feagan B.G. Lichtenstein G.R. Mayer L.F. Schreiber S. Colombel J.F. Rachmilewitz D. Wolf D.C. Olson A. Bao W. Rutgeerts P. 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Incidence and importance of antibody responses to infliximab after maintenance or episodic treatment in Crohn’s disease.Clin Gastroenterol Hepatol. 2004; 2: 542-553Google ScholarAdalimumab (Humira; Abbott Laboratories, Abbott Park, IL) is a subcutaneously administered, recombinant, fully human, immunoglobulin G1 monoclonal antibody that binds with high affinity and specificity to human TNF, but not lymphotoxin, and modulates biologic responses induced or regulated by TNF. Controlled trials have demonstrated the efficacy of adalimumab in the treatment of patients with rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis (all 3 Food and Drug Administration–approved indications)13den Broeder A. van de Putte L. Rau R. Schattenkirchner M. Van Riel P. Sander O. Binder C. Fenner H. Bankmann Y. Velagapudi R. Kempeni J. Kupper H. 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Radiographic, clinical, and functional outcomes of treatment with adalimumab (a human anti-tumor necrosis factor monoclonal antibody) in patients with active rheumatoid arthritis receiving concomitant methotrexate therapy: a randomized, placebo-controlled, 52-week trial.Arthritis Rheum. 2004; 50: 1400-1411Google Scholar, 16Mease P.J. Gladman D.D. Ritchlin C.T. Ruderman E.M. Steinfeld S.D. Choy E.H. Sharp J.T. Ory P.A. Perdock R.J. Weinberg M.A. Adalimumab Effectiveness in Psoriatic Arthritis Trial Study GroupAdalimumab for the treatment of patients with moderately to severely active psoriatic arthritis: results of a double-blind, randomized, placebo-controlled trial.Arthritis Rheum. 2005; 52: 3279-3289Google Scholar, 17Rau R. Simianer S. van Riel P.L. van de Putte L.B. Kruger K. Schattenkirchner M. Allaart C.F. Breedveld F.C. Kempeni J. Beck K. Kupper H. Rapid alleviation of signs and symptoms of rheumatoid arthritis with intravenous or subcutaneous administration of adalimumab in combination with methotrexate.Scand J Rheumatol. 2004; 33: 145-153Google Scholar, 18van de Putte L.B. Rau R. Breedveld F.C. Kalden J.R. Malaise M.G. van Riel P.L. Schattenkirchner M. Emery P. Burmester G.R. Zeidler H. Moutsopoulos H.M. Beck K. Kupper H. Efficacy and safety of the fully human anti-tumour necrosis factor alpha monoclonal antibody adalimumab (D2E7) in DMARD refractory patients with rheumatoid arthritis: a 12 week, phase II study.Ann Rheum Dis. 2003; 62: 1168-1177Google Scholar, 19van de Putte L.B. Atkins C. Malaise M. Sany J. Russell A.S. van Riel P.L. Settas L. Bijlsma J.W. Todesco S. Dougados M. Nash P. Emery P. Walter N. Kaul M. Fischkoff S. Kupper H. Efficacy and safety of adalimumab as monotherapy in patients with rheumatoid arthritis for whom previous disease modifying antirheumatic drug treatment has failed.Ann Rheum Dis. 2004; 63: 508-516Google Scholar, 20Weinblatt M.E. Keystone E.C. Furst D.E. Moreland L.W. Weisman M.H. Birbara C.A. Teoh L.A. Fischkoff S.A. Chartash E.K. Adalimumab, a fully human anti-tumor necrosis factor alpha monoclonal antibody, for the treatment of rheumatoid arthritis in patients taking concomitant methotrexate: the ARMADA trial.Arthritis Rheum. 2003; 48: 35-45Google Scholar, 21Weisman M.H. Moreland L.W. Furst D.E. Weinblatt M.E. Keystone E.C. Paulus H.E. Teoh L.S. Velagapudi R.B. Noertersheuser P.A. Granneman G.R. Fischkoff S.A. Chartash E.K. Efficacy, pharmacokinetic, and safety assessment of adalimumab, a fully human anti-tumor necrosis factor-alpha monoclonal antibody, in adults with rheumatoid arthritis receiving concomitant methotrexate: a pilot study.Clin Ther. 2003; 25: 1700-1702Google Scholar as well as in psoriasis.22Haibel H. Rudwaleit M. Brandt H.C. Grozdanovic Z. Listing J. Kupper H. Braun J. Sieper J. Adalimumab reduces spinal symptoms in active ankylosing spondylitis.Arthritis Rheum. 2006; 54: 678-681Google Scholar, 23De Keyser F. Van den Bosch F. Mielants H. Anti-TNF-alpha therapy in ankylosis spondylitis.Cytokine. 2006; 33: 294-298Google Scholar, 24Gordon K.B. Bonish B.K. Patel T. Leonardi C.L. Nickoloff B.J. The tumour necrosis factor-alpha inhibitor adalimumab rapidly reverses the decrease in epidermal Langerhans cell density in psoriatic plaques.Br J Dermatol. 2005; 153: 945-953Google ScholarPreviously, a phase 3, 4-week, placebo-controlled induction trial, Clinical Assessment of Adalimumab Safety and Efficacy Studied as Induction Therapy in Crohn’s Disease (CLASSIC I), demonstrated that an adalimumab loading-dose regimen of 160 mg given subcutaneously at week 0 and 80 mg given subcutaneously at week 2 was significantly more effective than placebo in inducing remission in 299 patients with moderate to severe CD who were naive to TNF-antagonist therapy (36% vs 12%, P = .001).25Hanauer S.B. Sandborn W.J. Rutgeerts P. Fedorak R.N. Lukas M. MacIntosh D. Panaccione R. Wolf D. Pollack P. Human anti-tumor necrosis factor monoclonal antibody (adalimumab) in Crohn’s disease: the CLASSIC I trial.Gastroenterology. 2006; 130: 323-333Google Scholar More recently, CLASSIC II, a small, phase 2, randomized, placebo-controlled, maintenance follow-up trial to CLASSIC I, demonstrated that adalimumab 40 mg subcutaneously every other week or weekly was superior to placebo in maintaining remission over a 56-week period in 55 patients with moderate to severe CD naive to TNF-antagonist therapy who experienced remission with adalimumab induction therapy.26Sandborn W.J. Hanauer S. Enns R. Lukas M. Wolf D. Isaacs K. MacIntosh D. Panaccione R. Rutgeerts P. Pollack P. Maintenance of remission over 1 year in patients with active Crohn’s disease treated with adalimumab: results of CLASSIC II, a blinded, placebo-controlled study (oral presentation OP-G-353).Gut. 2005; 54: A81-A82Google ScholarIn this report, we describe the Crohn’s Trial of the Fully Human Antibody Adalimumab for Remission Maintenance (CHARM). CHARM was a large, phase 3, randomized, double-blind, placebo-controlled, 56-week study conducted in patients with moderate to severe CD who may or may not have previously received TNF-antagonist therapy. The findings presented here address the primary objective of the study, which was to assess the benefit of 2 adalimumab dosing regimens in maintaining clinical remission at 26 and 56 weeks in patients who had an initial response to 2 adalimumab injections of 80 mg at week 0 and 40 mg at week 2.Materials and MethodsPatientsCHARM included men and women 18–75 years of age with known CD of at least 4 months’ duration (radiologic/endoscopic confirmation required) that at the screening visits was moderately to severely active, as defined by a baseline Crohn’s Disease Activity Index (CDAI) score of 220–450 points. Concurrent therapies for CD, including stable dosages (for at least 4 weeks before screening) of azathioprine, 6-mercaptopurine, methotrexate, 5-aminosalicylates, sulfasalazine, oral mesalamine, and CD-related antibiotics, were permitted, as were stable dosages (for at least 2 weeks before screening) of prednisone (≤30 mg/day or equivalent) or budesonide (≤9 mg/day) (patients could not be on both prednisone and budesonide). Patients who had received infliximab or any TNF antagonist other than adalimumab more than 12 weeks before screening could be enrolled provided that they did not exhibit initial nonresponse to the agent (ie, no clinical response to first injection as judged by the investigator). Female patients of childbearing potential were required to use an effective form of birth control.Patients were excluded if they had ulcerative colitis, symptomatic obstructive disease, bowel resection within the past 6 months, an ostomy, extensive small bowel resection (as determined by the investigator), or short bowel syndrome; were currently receiving total parenteral nutrition; had a history of cancer, Listeria, human immunodeficiency virus, central nervous system demyelinating disease, or untreated tuberculosis; had received investigational chemical agents within 30 days or investigational biologic therapy within 3 months before screening; had received antibiotic treatment for non-CD–related infections within 3 weeks before screening; were pregnant or breast-feeding; had a history of significant drug or alcohol abuse within the past year; had poorly controlled medical conditions; had received treatment with adalimumab or participated in an adalimumab clinical study; had received enema therapy within 2 weeks before screening; had received cyclosporine, mycophenolate mofetil, or tacrolimus within 8 weeks of screening; had a positive Clostridium difficile stool assay; or had clinically significant deviations in prespecified laboratory parameters.Study DesignThis was a randomized, double-blind, placebo-controlled, multicenter efficacy and safety study conducted at 92 sites in Europe, the United States, Canada, Australia, and South Africa from July 2003 to September 2005. The institutional review board or independent ethics committee at each participating site approved the protocol, and written informed consent was obtained from all patients.Patients entered a 2-week screening period before their baseline assessments. At the baseline visit (week 0), all eligible patients received open-label adalimumab 80 mg subcutaneously followed by a 40-mg dose at week 2. At week 4, patients were randomized to one of 3 treatment groups (adalimumab 40 mg every other week, adalimumab 40 mg weekly, or placebo) and continued treatment through week 56. Also at week 4, patients were stratified by responder status (ie, whether or not they attained a decrease in CDAI of ≥70 points compared with baseline) and previous exposure to TNF antagonists. All patients were randomized centrally using an interactive voice response system. Patients, study coordinators, and study investigators were blinded to treatment assignment throughout the blinded portion of the study.After randomization, patients experiencing a disease flare (increase in CDAI of ≥70 points compared with week 4 and a CDAI score >220) or sustained nonresponse (did not attain a CDAI decrease of ≥70 points compared with baseline) at or after week 12 were switched to open-label treatment with 40 mg adalimumab every other week. This dosage could be escalated to open-label treatment with 40 mg weekly for those with continued nonresponse or recurrent flare. Continued nonresponse with the open-label 40-mg weekly dosage resulted in withdrawal from the study.At week 8, patients receiving corticosteroids who experienced a significant improvement in CD symptoms (decrease in CDAI of ≥70 points compared with baseline) could begin reducing their corticosteroid dosages. If a patient experienced a loss of clinical response (decrease in CDAI became <70 points lower than baseline on 2 consecutive visits), the dosage of prednisone or budesonide could be increased back to the dosage used at the beginning of the study.The coprimary efficacy end points were the percentage of week-4 responders (defined as a decrease in CDAI scores ≥70 points at week 4 compared with baseline: “randomized responders”) who achieved clinical remission (CDAI score <150) at weeks 26 and 56. Prespecified secondary end points and subgroup analyses included (1) percentage of patients with a clinical response (decrease in CDAI score from baseline by ≥70 points and by ≥100 points) at weeks 26 and 56; (2) changes from baseline in Inflammatory Bowel Disease Questionnaire (IBDQ) total scores at weeks 26 and 56; (3) percentage of patients in clinical remission at weeks 26 and 56 who were able to discontinue corticosteroid use; (4) percentage of patients in clinical remission at weeks 26 and 56 who were able to discontinue corticosteroid use for ≥90 days; (5) percentage of patients with fistula remission (closure of all fistulas that were draining at screening and baseline visits); (6) previous/concomitant use of immunosuppressants (with vs without), and previous use of TNF antagonists (experienced vs naive); and (7) median time in clinical remission among randomized responders achieving remission. Post-hoc analyses were conducted to evaluate the sustainability of response and the response in certain subgroups. These included (1) percentage of patients with fistula closure at 26 weeks who continued to have fistula closure at 56 weeks and (2) clinical remission rates stratified by baseline C-reactive protein (CRP) concentration (<1 vs ≥1 mg/dL).Efficacy and Safety EvaluationsPatients were assessed at weeks 0, 2, 4, 6, 8, 12, 16, 20, 26, 32, 40, 48, 56, and 60 (end of 4-week follow-up period). At each visit, the CDAI score was calculated, CRP concentration and the number of cutaneous fistulas draining upon gentle compression were assessed, adverse events and concomitant medications were recorded, and the following safety assessments were performed: vital signs, physical examination, hematologic analysis, serum biochemistry analysis, and urinalysis. The IBDQ was administered to assess patient-reported outcomes at weeks 0, 4, 12, 26, and 56.Statistical AnalysisWe estimated that 160 patients per treatment arm (total of 480 patients for primary analysis of week-4 responders) would provide a statistical power of 87% at a 0.05 α-level and 80% at an adjusted 0.025 α-level to detect a 14% absolute difference in clinical remission rates between adalimumab and placebo groups, assuming a 14% clinical remission rate in the placebo arm and a 28% remission rate in the adalimumab arms at week 56. This would also provide >90% power to test clinical remission rate at week 26. With an assumed 58% of patients achieving clinical response at week 4, approximately 830 patients were required at study baseline to allow 160 patients to be equally allocated to the 3 treatment arms at week 4.The primary efficacy end point analysis was performed on the randomized responder population, which included all treated patients who achieved clinical response (decrease in CDAI of ≥70 points) at week 4 and were randomized to receive one of 3 blinded treatments. Patients who switched to open-label therapy or who withdrew from the study altogether were counted as remission failures. Secondary efficacy analyses were conducted for all treated patients, including both the randomized responder and randomized nonresponder groups (all randomized patients who failed to achieve a clinical response at week 4). Secondary efficacy results presented here describe comparisons between both adalimumab dosage groups and the placebo group using the randomized responder population to support the primary efficacy analysis. Fistula results were evaluated among all randomized patients with draining fistulas at baseline and screening visits (both the randomized responders and the randomized nonresponders). According to the prespecified analysis plan, fistula data from both adalimumab dosing groups (every other week and weekly) were combined and compared with patients receiving placebo. The population for safety analyses consisted of all patients who received at least one dose of study medication.All analyses used 2-sided tests with an α-level of 0.05. For the primary efficacy analysis, the Cochran–Mantel–Haenszel χ2 test adjusting for previous TNF-antagonist use was used to compare the percentage of week-4 responders in clinical remission at weeks 26 and 56 between each adalimumab arm and the placebo treatment group. Patients without CDAI assessments at weeks 26 or 56 were classified as remission failures.For secondary efficacy analyses in the randomized responder population, continuous variables were compared using analysis of covariance adjusted for baseline value. Discrete variables were compared using the χ2 test. The numbers and percentages of patients experiencing adverse events were to be tabulated by body system and Medical Dictionary for Drug Regulatory Affairs–preferred terms. Investigators could report exacerbations of CD as adverse events (mandated by the Food and Drug Administration). However, reporting of CD as an adverse event was independent of qualifying a patient as a remission failure or experiencing a disease flare. Patients who met the protocol definition of flare (increase in CDAI of ≥70 points vs week 4 and total CDAI score >220) were switched out of the randomized treatment arm to open-label therapy. Once in open-label therapy, additional flares led to dosage escalation to weekly treatment. Adverse event results were summarized and reported by randomized treatment group.Role of the Funding SourceThis study was designed by selected study investigators (including J.-F.C., W.J.S., P.R., and S.B.H.) and staff members from Abbott Laboratories. Selected investigators and Abbott Laboratories’ staff members, including those who designed the study and analyzed and interpreted the data, wrote this manuscript and agreed to submit it for publication. The principal investigator (J.-F.C.) approved the content of the report before submission.ResultsPatient Disposition and Baseline CharacteristicsA total of 854 patients enrolled in the trial and received induction therapy with 80 mg of adalimumab at week 0 and 40 mg of adalimumab at week 2 (Figure 1). Of these, 76 withdrew before randomization at week 4. The most common reasons for study discontinuation were adverse events and lack of efficacy. The remaining 778 patients were randomized at week 4 to receive placebo (n = 261), adalimumab 40 mg every other week (n = 260), or adalimumab 40 mg weekly (n = 257). A total of 505 enrolled patients (59%) completed the 56-week study. Of these, 251 patients (50%) remained on their randomized, double-blind treatments, whereas 123 completed the study on open-label adalimumab 40 mg every other week and 140 completed the study on open-label adalimumab 40 mg weekly. Nine additional patients discontinued the study before week 56 but were included in the week-56 analysis by virtue of results imputed from their last visits (because these visits fell within the protocol parameters of the week-56 visit). Among all randomized patients, 273 patients (35%) withdrew before the end of the study (placebo group, 44%; adalimumab 40 mg every other week, 36%; adalimumab 40 mg weekly, 25%).Of the 854 patients enrolled in the trial, 499 (58%) responded to adalimumab induction and were randomized. These 499 patients comprised the randomized responder population assessed in the predefined primary efficacy end point analysis. The 279 nonresponders who were randomized at week 4 were included in the safety analysis. Baseline characteristics of the week-4 responders compared with nonresponders were similar (Table 1). Among the randomized responder population, 143 patients (29%) withdrew before the end of the study, with the percentage of withdrawals being similar in the placebo (35%) and adalimumab 40-mg every other week groups (33%) and lower in the adalimumab 40-mg weekly group (17%). The most common reason for study discontinuation in all 3 randomized responder groups was adverse events.Table 1Baseline Demographics and Clinical CharacteristicsCharacteristicAll patients (N = 854)Week-4 randomized respondersaAmong the patients randomized at week 4, there were no statistically significant differences between randomized responders and randomized nonresponders. CDAI and CRP values were statistically significantly greater for the patients randomized at week 4 versus the 76 patients who withdrew before week 4 randomization. (n = 499)Week-4 randomized nonrespondersaAmong the patients randomized at week 4, there were no statistically significant differences between randomized responders and randomized nonresponders. CDAI and CRP values were statistically significantly greater for the patients randomized at week 4 versus the 76 patients who withdrew before week 4 randomization. (n = 279)Nonrandomized (week 4 withdrawals)aAmong the patients randomized at week 4, there were no statistically significant differences between randomized responders and randomized nonresponders. CDAI and CRP values were statistically significantly greater for the patients randomized at week 4 versus the 76 patients who withdrew before week 4 randomization. (n = 76)Male patients, n (%)326 (38.2)188 (37.7)108 (38.7)30 (39.5)Age (y), mean (SD)37.1 (11.9)36.7 (11.6)37.9 (11.8)36.1 (13.6)Body wt (kg), mean (SD)70.5 (17.8)70.2 (17.8)72.1 (18.0)67.1 (15.9)Involved intestinal area, n (%)bPatient could have had multiple CD locations. Colonic640 (74.9)375 (75.2)206 (73.8)59 (77.6) Ileal621 (72.7)357 (71.5)214 (76.7)50 (65.8) Gastroduodenal43 (5.0)30 (6.0)10 (3.6)3 (3.9) Other129 (15.1)68 (13.6)44 (15.8)17 (22.4)Enterocutaneous or perianal fistula at both screening and baseline, n (%)130 (15.2)64 (12.8)53 (19.0)13 (17.1)Baseline CDAI score, mean (SD)313.1 (62.0)cOne unrandomized patient did not have a baseline CDAI score.316.6 (62.5)301.6 (56.4)333.3 (70.8)IBDQ, median (range)dScores for the IBDQ can range from 32 to 224; higher scores indicate a better quality of life.122.0 (44–205)125.0 (44–196)120.0 (55–197)112.5 (27.7)CRP (mg/dL) Mean (SD)2.3 (3.4)2.4 (3.7)1.8 (2.2)3.6 (4.1) Median (range)0.9 (0.02–35.0)0.9 (0.02–35.0)0.9 (0.02–12.3)1.89 (0.03–18.8)CRP concentration ≥1.0 mg/dL (10 mg/L), n (%)407 (47.7)236 (47.3)126 (45.2)45 (59.2)Previous TNF-antagonist exposure, n (%)424 (49.6)238 (47.7)152 (54.5)34 (44.7)Concomitant medication, n (%) Any corticosteroideIncludes betamethasone, budesonide, dexamethasone, deflazacort, cortisone, cloprednol, fluocortolone, glucocorticoids, glucocorticosteroids, hydrocortisone, methylprednisolone, prednisolone, prednisone, paramethasone, and prednylidene.376 (44.0)210 (42.1)129 (46.2)37 (48.7) Prednisone244 (28.6)130 (26.1)86 (30.8)26 (34.2) Budesonide100 (11.7)48 (9.6)39 (14.0)13 (17.1) Any immunosuppressive agent399 (46.7)240 (48.1)126 (45.2)33 (43.4) Azathioprine275 (32.2)165 (33.1)88 (31.5)19 (25.0) 6-Mercaptopurine81 (9.5)38 (7.6)27 (9.7)14 (18.4) Methotrexate90 (10.5)49 (9.8)29 (10.4)9 (11.8) 5-aminosalicylatesfAminosalicylic acid, balsalazine, mesalazine, olsalazine, sulfasalazine.334 (39.1)206 (41.3)100 (35.8)28 (36.8)Current smoker, n (%)303 (35.5)176 (35.3)101 (36.2)26 (34.2)a Among the patients randomized at week 4, there were no statistically significant differences between randomized responders and randomized nonresponders. CDAI and CRP values were statistically significantly greater for the patients randomized at week 4 versus the 76 patients who withdrew before week 4 randomization.b Pat