Cut-off ranges of infliximab serum levels in Crohn's disease in the clinical practice

INTRODUCTION

between 30 % and 40 % of patients treated with infliximab lose response during maintenance. Therapeutic drug monitoring could be used to optimize management in these situations. However, infliximab serum levels are not well defined. The aim of this study was to determine the cut-off range of infliximab serum levels in Crohn's disease patients in remission in the clinical practice.

METHODS

an observational retrospective study was performed from 2016 to 2017. Patients were included with established Crohn's disease, who had been on a maintenance dose schedule of infliximab. Infliximab levels and antibodies to infliximab were measured at least twice in all patients, after induction and after six months of treatment. Clinical remission was defined as ≤ 4 using the Harvey-Bradshaw index. Cluster analysis was used to analyze the results.

RESULTS

one hundred and five Crohn's disease patients were included in the study; 57.1 % were male with a mean age of 39 years (SD ± 12.9). The median (range) time of the disease was eleven years (7-15) and the median (range) time of follow-up was 32 months (22-38). Patients who achieved remission had infliximab serum levels between 4.26-8.26 ug/ml versus 0.06-1.43 ug/ml in patients who did not achieve remission after induction. Infliximab serum levels were 2.84-7.75 ug/ml and 0.05-2.69 ug/ml in patients who achieved remission versus those who did not achieve remission after six months of treatment. Overall, 4.26-8.26 ug/ml was found to be the best cut-off range for remission.

CONCLUSIONS

in our clinical practice, serum levels of infliximab in Crohn's disease patients should be higher than 4 ug/ml to achieve clinical remission.

Long-term follow up after switching from original infliximab to an infliximab biosimilar: real-world data

BACKGROUND

Several studies have reported positive efficacy outcomes for patients with inflammatory bowel disease treated with CT-P13, an infliximab biosimilar. Data from follow-up periods longer than 1 year are still scarce. Here, we assessed the long-term efficacy data, loss of response and safety after switching from infliximab to CT-P13 in patients with inflammatory bowel disease.

METHODS

This was a prospective single-center observational study involving patients with moderate-to-severe Crohn's disease and ulcerative colitis switched from infliximab to CT-P13 treatment and reviewed up to 24 months. Efficacy and loss of response were measured using the Harvey-Bradshaw (HB) index and partial Mayo score for patients with Crohn's disease and ulcerative colitis respectively. C-reactive protein, infliximab drug levels, adverse events and antidrug antibodies were also monitored throughout the study.

RESULTS

A total of 64 patients with Crohn's disease and 36 patients with ulcerative colitis were included. Most of them (72%) remained on CT-P13. Overall, 28% of patients discontinued the therapy due to loss of response, adverse events or long-lasting clinical remission. Remission at 18 and 24 months occurred in 69.9% and 68.5% of patients, respectively. Dose increase was performed in 22% of patients, with remission being reached in 60% of them. HB index, partial Mayo score, C-reactive protein and infliximab drug levels did not show significant changes. Serious adverse events were reported in 14% of patients. Overall, two patients developed low levels of antidrug antibodies.

CONCLUSIONS

Most of the patients switching from original infliximab were maintained on CT-P13 at 2 years of follow up with a good profile of efficacy and safety.

Switching from reference infliximab to CT-P13 in patients with inflammatory bowel disease: results of a multicenter study after 12 months

BACKGROUND AND AIMS

infliximab has changed the natural history of inflammatory bowel disease (IBD). The advent of biosimilar treatments such as CT-P13 will hopefully improve the availability of biological therapies. Data with regard to drug switching are currently limited. The objective of the study was to assess the effectiveness and safety of switching from the reference product (RP), infliximab, to CT-P13 in patients with IBD.

METHODS

this was a multicenter prospective observational study in patients with Crohn's disease (CD) and ulcerative colitis (UC). All patients had switched from infliximab RP (Remicade®) to CT-P13 treatment and were followed up for 12 months. The efficacy endpoint was the change in clinical remission assessed at 0 and 12 months, according to the Harvey-Bradshaw score and partial Mayo score for patients with CD and UC, respectively. Adverse events were monitored and recorded throughout the study.

RESULTS

a total of 167 patients (116 CD/51 UC) were included; 88.8% (103/116) of patients with CD were in remission at the time of the drug switch and 69.7% were in remission at 12 months. The Harvey-Bradshaw (HB) score significantly changed at 12 months (p = 0.001); 84.3% (43/51) of patients with UC were in remission at the time of the drug switch and 76.7% were in remission at 12 months. No significant changes in the median partial Mayo score (p = 0.87) were observed at 12 months. Serious adverse events related to medication were reported in 12/167 (7.2%) cases.

CONCLUSION

switching from infliximab RP to CT-P13 is safe and effective at 12 months. The loss of efficacy at 12 months was 15.7%.

Loss of efficacy and safety of the switch from infliximab original to infliximab biosimilar (CT-P13) in patients with inflammatory bowel disease

BACKGROUND

Infliximab original has changed the natural history of inflammatory bowel diseases (IBD) over the past two decades. However, the recent expiration of its patent has allowed the entry of the first Infliximab biosimilar into the European and Spanish markets. Currently switching drugs data in IBD are limited.

AIM

To compare the efficacy of infliximab biosimilar, CT-P13, against infliximab original, analyzing the loss of response of both at the 12 mo follow-up in patients with IBD.

METHODS

An observational study of two cohorts has been conducted. One retrospective cohort that included patients with IBD treated with Infliximab original, and a prospective cohort of patients who were switching from infliximab original to infliximab biosimilar (CT-P13). We had analyzed the overall efficacy and loss of efficacy in patients in remission at the end of one year after treatment with the original drug compared to the results of the year of treatment with the biosimilar.

RESULTS

98 patients (CD 67, CU 31) were included in both cohorts. The overall efficacy for infliximab original per year of treatment was 71% vs 68.2% for infliximab biosimilar (P = 0.80). The loss of overall efficacy at 12 mo for infliximab original was 6.6% vs 14.5% for infliximab biosimilar (P = 0.806). The loss of efficacy in patients who were in basal remission was 16.3% for infliximab original vs 27.1% for infliximab biosimilar. Adverse events were 9.2% for infliximab original vs 11.2% for infliximab biosimilar.

CONCLUSION

The overall efficacy and loss of treatment response with infliximab biosimilar (CT-P13) is similar to that observed with infliximab original in patients who were switching at the 12 mo follow-up. There is no difference in the rate of adverse events.

Evolution of the incidence of inflammatory bowel disease in Southern Spain

BACKGROUND

The incidence of inflammatory bowel disease is increasing in Europe and in Spain. However, there is no recent data from Southern Spain.

OBJECTIVES

To determine the evolution of the hospital incidence of inflammatory bowel disease in Southern Spain.

MATERIAL AND METHODS

A retrospective study was performed in two hospitals in Southern Spain. Data was collected from inflammatory bowel disease patients, divided into two periods (1995-2000 and 2001-2014) and compared. The reference population from both areas was 1,011,555 inhabitants.

RESULTS

A total of 430 patients were registered during the first period (1995-2000); 50% (215) had Crohn's disease that resulted in a cumulative incidence rate of 7.08 cases/100,000 inhabitants per year. The overall inflammatory bowel disease incidence was 3.54 cases/100,000 inhabitants per year. During the second period (2001-2014), 2,089 patients were collected; 51.7% had ulcerative colitis (1,081). The rate of cumulative incidence of inflammatory bowel disease was 14.7 cases/100,000 inhabitants per year (7.6 cases of ulcerative colitis/100,000 inhabitants/year and 7.1 cases of Crohn´s disease/100,000 inhabitants/year).

CONCLUSIONS

The incidence of inflammatory bowel disease in Southern Spain has doubled in the last decade and is similar to that of the rest of the country and Europe.