Among a real-world cohort of patients, switching between infliximab biosimilars was effective and well tolerated, although retention was higher among those who had initially started on the originator product.
While providers are becoming more familiar with the idea of switching patients from reference biologics to biosimilars, it is less common to switch from one biosimilar to another. However, nonmedical switching among biosimilars may occur to save costs.
A study of more than 1500 patients in a real-world setting found switching between infliximab biosimilars was effective and well tolerated. The findings were presented at EULAR 2022, the annual meeting of the European Alliance of Associations for Rheumatology.
The observational cohort study was based on the DANBIO registry and investigated the effectiveness of switching patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and axial spondyloarthritis (AxSpA) from CT-P13 to GP1111. The study included patients who had been switched from the originator to CT-P13 and patients who had never received the originator product.
Patients were included if they had experienced a biosimilar-to-biosimilar switch between April 1, 2019, and February 1, 2020. The main outcomes were treatment retention on GP1111 after 1 year and changes in disease activity from the 4 months prior to the switch compared with the 4 months after the switch.
The study included 1171 patients who were originator naïve and 434 who had already switched from the originator. Among the full population, 685 had RA, 314 had PsA, and 606 had AxSpA. The median disease duration was 9 years. Slightly less than half (42%) were in remission at the time of the switch, according to the Disease Activity Score 28-joint count or Ankylosing Spondylitis Disease Activity Score.
Patients who had been on the originator product had a greater 1-year retention. One year after the switch, 83% (95% CI, 81%-85%) of patients who had never been on the originator maintained GP1111 treatment compared with 92% (95% CI, 90%-95%) of those who had initially switched from the originator. Among patients with RA and PsA, the risk of GP1111 withdrawal was lower among those who had been on the originator; however, there was no significant difference among patients with AxSpA.
For both groups, changes in disease activity were close to zero when comparing the 4 months prior with the 4 months after the switch. Lower disease activity at baseline was associated with higher retention across all 3 disease states. Having 1 or more comorbidities at baseline was also associated with a higher retention of GP1111 at 1 year.
According to the researchers, the difference in retention between the 2 groups suggests “retention to be more affected by patient-related than drug-related factors.” Overall, the biosimilar-to-biosimilar switch was effective and well tolerated.
According to The Center for Biosimilars®, switching among biosimilars was becoming “increasingly common” in 2019, particularly in countries that utilize tenders for medicines and may ask patients to transition based on the outcomes of tenders.
In 2019, studies presented at United European Gastroenterology Week 2019 and the 6th Congress of Skin Inflammation and Psoriasis International Network had similarly supported the safety and efficacy of multiple biosimilar switching.
Nabi H, Hetland ML, Loft AG, et al. Infliximab biosimilar-to-biosimilar switching in patients with inflammatory rheumatic diseases: clinical outcomes in real-world patients from the DANBIO registry. Presented at: EULAR 2022; June 1-4, 2022; Copenhagen, Denmark. Abstract OP0065.