The two major forms of inflammatory bowel disease (IBD), encompassing Crohn’s disease (CD) and ulcerative colitis (UC), are chronic immune-mediated conditions characterised by an increased production of pro-inflammatory cytokines that act as critical drivers of intestinal inflammation. Anti-cytokine therapy has been shown to improve clinical outcomes in IBD. Janus kinases (JAKs) are tyrosine kinases that bind different intracellular cytokine receptors, leading to phosphorylation of signal transducer and activation of transcription molecules implicated on targeted gene transcription. Four isoforms of JAKs have been described: JAK1, JAK2, JAK3 and TYK2. Oral JAK inhibitors (JAKi) have been developed as synergic anti-cytokine therapy in IBD, showing different selectivity towards JAK isoforms. Tofacitinib, a pan-JAK inhibitor, has been recently approved for the treatment of moderate-to-severe UC. With the aim of improving the benefit: risk ratio of this drug class, several second-generation subtype-selective JAKi are under development. However, whether selective inhibition of JAK isoforms is associated with an increased clinical efficacy and/or a better safety profile remains debatable. The aim of this review is to critically review the preclinical and clinical data for the differential selectivity of JAK inhibitors and to summarise the potential clinical implications of the selective JAK inhibitors under development for UC and CD.

Introduction: Sphingosine-1-phosphate (S1P) is a membrane-derived lysophospholipid signaling molecule implicated in various physiological and pathological processes, such as regulation of the immune, cardiovascular, pulmonary, and nervous systems and theoretical cancer-related risks, through extracellular activation of S1P1-5 receptors. Areas covered: S1P receptor agonism is a novel strategy for the treatment of UC targeting lymphocyte recirculation, through blockade of lymphocyte egress from lymph nodes. We conducted an extensive literature review on PUBMED on currently available data on molecular aspects of S1P modulation, the mechanisms of action of S1PR agonists (fingolimod, ozanimod, etrasimod, and KRP-203), and their potential efficacy and safety for the treatment of patients with ulcerative colitis. Expert opinion: Selective S1P modulators have emerged to enlarge the efficacy and safety profile of this class of agents. Phase 3 programs should add the potential body of evidence to prove their benefit for the management of UC patients.

Introduction Biosimilars represent great potential in cost saving and re-investment opportunities in healthcare and allow patients greater access to effective mAbs. Infliximab biosimilars are successfully used in all indications for whom the reference product (RP) was approved. Areas covered In late 2018, adalimumab biosimilars will also be available in patients with inflammatory bowel disease (IBD). ABP501, BI 695501, GP2017, and SB5 have been approved by the EMA for the same indications of the reference product (RP, Humira®). Preclinical data show high similarity between all biosimilars and the RP. Clinical data in patients with rheumatoid arthritis and psoriasis also show no differences in terms of efficacy, safety, and immunogenicity. Data in IBD patients are still lacking. Expert opinion Biosimilars of adalimumab appear to be clinically equivalent to the RP. Decisions based on choosing the ideal patient to receive or to be switched to a biosimilar of adalimumab, or choosing one biosimilar vs. another, or cross-switching among biosimilars remain the next challenge in the field of IBD.

Introduction: Currently, mucosal healing is considered as a composite treatment end-point in inflammatory bowel disease (IBD) since it has been demonstrated to improve disease-related outcomes. The definition of mucosal healing has evolved and current evidence suggests that in addition to endoscopic healing the achievement of histological remission (HR) represents a potential novel target in the management of IBD in relation to better long-term disease outcomes. Areas covered: We aimed to review the current literature on HR in ulcerative colitis and discuss its limitations and advantages when adopting this potential new target as an ultimate treatment outcome in clinical trials and routine clinical practice. Expert Opinion: HR is achievable in UC with different rates in conventional therapies, biological and novel drugs. Targeting HR in UC lowers the risk of hospitalizations, colectomy and colorectal cancer. HR occurs later than endoscopic remission, longer treatment courses are associated with higher HR assessment. This might imply modifying monitoring time schedules and algorithms. Prospective data are needed to support histological healing as a new treatment target in UC.