Assessment of Biologic Treatment Outcomes in Inflammatory Bowel Disease Patients with 'Early Disease': Results of a Systematic Literature Review

Introduction: Early disease control with biologic treatment (Tx) in patients (pts) with inflammatory bowel disease (IBD) may modify the disease course; however, this may depend on pts' disease characteristics and risk of disease progression, and needs to be assessed using outcomes indicative of long-term disease modification. This systematic literature review (SLR) evaluated biologic Tx outcomes in ‘early' Crohn's disease (CD) and ulcerative colitis (UC) pts. Methods: The Cochrane library, MEDLINE and EMBASE were searched using key words and indexing terms. Eligible papers reported the characteristics and outcomes of adult pts (≥18 years) with ‘early' (not pre-defined) CD or UC treated with a first-line biologic in a clinical or observational study published from January 2008 to March 2018. Key terms (e.g., ‘early', ‘naïve', ‘newly diagnosed') identified relevant studies. Studies not reported in English, in pediatric or non-IBD pts were excluded. Results: Nineteen studies in CD (6 clinical; 13 observational), 3 in UC and 1 in CD and UC (all observational) were identified. Studies evaluated the effectiveness of infliximab (CD: 15 papers, UC: 4 papers), adalimumab (CD: 9 papers, UC: 3 papers) and certolizumab pegol (CD: 4 papers) as mono- or combination Tx with conventional therapy; 6 CD and 3 UC studies evaluated >1 biologic. Risk factors for disease progression were reported at baseline in select studies (e.g., prior hospitalization: 0 studies in CD, 1 [25%] study in UC; perianal/fistulizing disease: 7 [35%] studies in CD; proctitis: 1 [25%] study in UC). Outcomes were assessed at >54 weeks in 10 (50%) CD studies and 3 (75%) UC studies. CD-related surgery, an outcome indicative of disease modification, was assessed in 9 (45%) CD studies. Of these, 5 compared outcomes in patients treated early versus late (defined by time since diagnosis in 4 and treatment pathway in 1); 3 identified a significantly lower proportion or risk of CD-related surgery in patients treated early and 2 found no association. Conclusion: Few studies have evaluated the impact of early disease control with biologic Tx, especially in UC. More thorough consideration of pts' baseline risk of disease progression and assessment of longterm outcomes that are markers of disease progression is required to evaluate the effectiveness of early biologic use in achieving disease control. Furthermore, consistency in the measure of these outcomes across studies would support comparison of interventions.