Abstract Background Clinical trials have demonstrated that subcutaneous infliximab (IFX-SC) is not inferior to intravenous infliximab (IFX-IV). However, due to its superior pharmacokinetic properties, IFX-SC is now considered a “biobetter”. This study aims to assess whether these improved pharmacokinetic features translate into differences in persistence and efficacy in real-world practice. Methods A prospective observational study was conducted including patients with active inflammatory bowel disease initiating IFX-IV or IFX-SC based on medical criteria, cost considerations, or patient preference. The objectives were to compare persistence rates, concomitant medication use, clinical response, and biomarker outcomes between the two groups. Results To date, 205 patients have been recruited from 19 different centers. Of these, 83 (52 IFX-IV, 31 IFX-SC) completed the follow-up visit at months 4–7. Use of immunosuppressants was significantly higher in the IFX-IV group (IFX-SC 9.6% vs. IFX-IV 38.4%, p = 0.005). Corticosteroid use was also higher in the IFX-IV group but did not reach statistical significance (IFX-SC 3.2% vs. IFX-IV 9.6%, p = 0.4). One patient per group switched administration route, while dose intensification was more frequent in the IFX-IV group (IFX-SC 3.2% vs. IFX-IV 40.4%, p = 0.001). A total of 9 patients discontinued treatment (IFX-SC 13% vs. IFX-IV 9.6%, p = 0.72), most due to pharmacodynamic failure (55.5%). The mean drug level was 16.7 µg/mL for IFX-SC and 11.3 µg/mL for IFX-IV. No significant differences in clinical or biomarker-based efficacy were observed between groups (Table 1). IFX-SC was the preferred route among patients, whereas economic reasons were the main determinant for selecting IFX-IV (Figure 1). Conclusion In this multicenter real-world cohort, subcutaneous infliximab demonstrated pharmacokinetic advantages and similar rates of treatment persistence and efficacy compared to the intravenous formulation, with a lower need for concomitant immunosuppression and dose intensification. Patients showed a statistically significant preference for the IFX-SC route of administration. Conflict of interest: Dr. González Partida, Irene: I have received funding for training and/or promotional talks from Amgen, Abbvie, Biogen, Falk, Kern Pharma, Johnson&Johnson, Lilly, Pfizer, Takeda and Tillots. De Lucas, Rocio: No conflict of interest Calvo, María: I have received funding for training and/or promotional talks from Amgen, Abbvie, Biogen, Falk, Kern Pharma, Johnson&Johnson, Lilly, Pfizer, Takeda and Tillots. Miranda-Bautista, Jose: No conflicts Olmos Jerez, Jose: I declare that I have no conflict of interest in this study. Rueda Garcia, Jose Luis: José Luis Rueda García has received financial support for traveling and educational activities from Kern Pharma, Abbvie, Johnson&Johnson, Pfizer, Eli Lilly, Takeda, Ferring, Tillotts Pharma, Faes Farma, Norgine and Casen and he has received fees as a speaker from Abbvie, Johnson&Johnson, Pfizer, Eli Lilly and Takeda. Garcia De La Filia Molina, Irene: I have no conflicts of interest Martin, Daniel: I have served as speaker for and received consulting fees from Abbvie, Takeda, Jansen, Ferring, Tillots, Dr. Falk Pharma, Faes Pharma an Persan Hernandez Camba, Alejandro: No conflict of interest Sola Sánchez, Javier: Has served as speaker for Takeda, Abbvie, Amgen and Sanofi García-Castellanos, Raquel: none Olmedo Moreno, Cristina: I declare to have received support for educational meetings from Abbvie, Takeda, Sandoz, Janssen and Alfasigma. Matallana Royo, Virginia: I have received fees as a speaker and consultant from Abbvie, Allergan, Casen Recordati, Italfármaco S.A., Janssen Cilag S.A., Merck Sharp & Dohme Española S.A., Pfizer, Schwabe Farma Ibérica S.A.U., and Takeda Calvo Moya, Marta Isabel: No conflict of interest Botella Mateu, Belén: No conflicts
Partida et al. (Thu,) studied this question.