The Sincerest Form of Flattery? Biosimilars in Inflammatory Bowel Disease

Reverse switching from the biosimilar SB2 to the originator infliximab in previously switched patients with inflammatory bowel diseases: results of a prospective long-term cohort study

BACKGROUND

Data regarding multiple switches including reverse switching between infliximab and its biosimilars are scarce in the field of inflammatory bowel diseases (IBD).

OBJECTIVES

We investigated the clinical effectiveness as primary outcome measure after repeated switches. Secondary endpoints included C-reactive protein (CRP) levels, immunogenicity (trough levels (TL); anti-drug antibodies (ADA), safety and drug persistence.

DESIGN

This study is a prospective, single-centre, observational cohort study. IBD patients receiving originator infliximab were switched to biosimilar SB2 and then reverse switched after 96 weeks and followed up for another 48 weeks.

METHODS

Clinical disease activity (Harvey-Bradshaw-index (HBI) in Crohn's disease (CD), partial Mayo score (pMS) in ulcerative colitis (UC)), CRP, TL, ADA, therapy-discontinuations and (serious) adverse events ((S)AE)) were monitored throughout the study.

RESULTS

Ninety-five patients (60 CD, 38 female) were enrolled. The median HBI was 2 (interquartile range (IQR) 1-4) at baseline and 2 (1-4) at week 48, resulting in a mean intra-individual change of 0.0 (standard deviation (SD) 1.5). The median pMS was 1 (IQR 0-1) at baseline and 0.5 (0-1) at week 48 resulting in a mean intra-individual change of 0.0 (SD 0.8). Clinical remission was achieved in 80% at baseline and 82% at week 48. Median CRP 2.0 mg/l (IQR 1.0-4.1) at baseline and 2.4 mg/l (1.1-5.2) at week 48 resulted in a mean change of 1.7 (SD 5.8) and no significant differences in CD (p = 0.3) and UC (p = 0.9). Median TL were 7.2 µg/ml (IQR 3.8-19.3) at baseline and 5.5 µg/ml (3.5-13.1) at week 48, resulting in a mean change of -1.0 (SD 7.4) with no statistical significance (CD p = 0.26, UC p = 0.41). De-novo-ADA were developed by 3.4%. The discontinuation rate was 14.7%. Safety signals were consistent with previous studies.

CONCLUSION

Reverse switching had no impact on efficacy of infliximab therapy in our cohort of IBD patients. The switch didn't influence immunogenicity or safety of therapy.

Attitudes, perceptions and barriers in implementing therapeutic drug monitoring for anti-TNFs in inflammatory bowel disease: a survey from the Middle East

BACKGROUND

A growing body of evidence underscores the beneficial impact of therapeutic drug monitoring (TDM) on the efficacy and cost-effectiveness of anti-tumour necrosis factor (TNF) therapy in patients with inflammatory bowel disease (IBD).

OBJECTIVES

We surveyed clinician attitudes, perceptions and barriers related to TDM in IBD in the Middle East.

DESIGN

A 15-question survey was distributed through national gastroenterological societies in five Middle Eastern countries (UAE, Saudi Arabia, Kuwait, Lebanon and Egypt).

METHODS

Data on clinician characteristics, demographics, utilization patterns and obstacles related to the adoption of TDM with anti-TNFs were gathered. Logistic regression analysis was used to predict factors influencing the utilization of TDM.

RESULTS

Among 211 respondents (82% male), 82% were consultants, 8% were physicians with an interest in gastroenterology (GI), and 6% were GI trainees. Of these, 152 met inclusion criteria, treating >5 IBD patients per month and ⩾1 with an anti-TNF per month. TDM was used in clinical practice by 78% (95% CI: 71-85) of respondents. TDM was utilized following the loss of response (LOR) in 93%, for primary non-response (PNR) in 40% and before restarting anti-TNF therapy after a drug holiday in 33% of respondents, while 34% used TDM proactively. No specific factors were associated with the use of TDM. Barriers to TDM use included cost (85%), time lag to results (71%) and lack of insurance reimbursement (65%). Overall knowledge of TDM (70%), interpretation and actioning of results (76%) or awareness of clinical guidelines (57%) were not perceived as barriers. If barriers were removed, 95% would use TDM more frequently; 93% for LOR, 60% for PNR, 50% when restarting after a drug holiday, and 54% would use TDM proactively.

CONCLUSION

Most gastroenterologists use TDM for LOR, with cost, time lag and insurance reimbursement being significant barriers. Addressing these barriers would increase the judicious use of reactive and proactive TDM to optimize anti-TNF therapy in IBD.