A European study of patients with inflammatory bowel disease (IBD) who initiated therapy with Humira® or an adalimumab biosimilar, or switched to a biosimilar found that outcomes and satisfaction were extremely high among all cohorts. But that statement is not surprising, based on cumulative experience with biosimilars. The study does suggest another very relevant conclusion, however.
The authors of this investigation surveyed gastroenterologists in five European countries who provided medical data regarding their de-identified patients with IBD who received either Humira or the biosimilar Amjevita® from 2020 to 2021. The patients were asked to complete health-related quality-of-life, disease activity, and daily functioning questionnaires. A total of 239 patients (who had not previously received a TNF-inhibitor) were initiated on Amjevita therapy; 90 of whom completed the patient surveys. A cohort of 136 patients had started Humira treatment and after a median 14 months of therapy, switched to Amjevita, and 73 completed the patient surveys. The patient groups were well matched for use of previous and concomitant therapies.
Of the patients first treated with Amjevita, 92% of the gastroenterologists surveyed reported being satisfied with the outcome of therapy. Of those patients switching to Amjevita, 98% of their physicians reported being satisfied with the treatment results. Ninety-six percent of patients in both groups reported they were satisfied with their health-related quality of life.
What the study does not point out is that patients who switched from Humira, were generally switching from the high-concentration therapy (40 mg/0.4 mL) to Amjevita in a low-concentration form (40 mg/0.8 mL). The study publication did not appear to capture what percent of patients taking Humira were using the high-concentration vs. low-concentration injections; the high-concentration form is dominant in the US. According to one study, AbbVie did not offer a citrate-free version of Humira in the low-concentration form at that time.
This real-world evidence suggests that the argument that the low-concentration form is somehow inferior to the high-concentration formulation is not true. The difference in concentration simply amounts to the volume of adalimumab that needs to be injected. An expectation of significantly fewer complaints about injection-site adverse events with the high-concentration form did not translate into lower satisfaction among those who switched to the biosimilar. Overall, patient and physician satisfaction was not different based on drug concentration, even for those who switched directly from the high- to the low-concentration form of adalimumab.
There has been much made of the availability (and interchangeability) of high-concentration injection for the various adalimumab biosimilars. The fact that no interchangeable, high-concentration biosimilar existed until late February was considered a hindrance to biosimilar uptake. However, the real-world evidence introduced by these researchers strongly suggest that injection volume has little or no effect on patient or physician satisfaction with therapy. Therefore, a low-concentration injection of adalimumab biosimilar (which we assume applies to any biosimilar, not just Amjevita), would yield similar results.
Consider that this concentration question weighed heavily in the minds of biosimilar manufacturers regarding their development and launch decisions. This research infers that a great deal of effort, resources, and time may have been more efficiently spent in other ways than on developing dual-concentration options.
In Related Biosimilar News
We’ve published extensively on the very limited uptake of adalimumab biosimilars in 2023. In a sea of vast competition, biosimilars only secured 3% of utilization in the category. However, the hopeful manufacturers launching that year had to produce and secure inventory as if they expected to gain significant marketshare. This resulted in another significant negative financial consequence of a difficult year for Adalimumab Biosimilar manufacturers in 2023.
Coherus Biosciences’ recent 2023 earnings presentation demonstrated it in stark terms, when the company announced a $47 million write down for Yusimry® inventory that went unused. This was likely experienced by the other eight biosimilar competitors who did not sell their inventory 2023.
