In Iceland, Switch to Adalimumab Biosimilar Reveals Issues With Injection Device

As the US market awaits competition for Humira next year, a new study from Iceland shows how patient acceptance of adalimumab biosimilars may come down to the injection itself.

In other words, the pen matters.

Adalimumab, developed by AbbVie as Humira, is a tumor necrosis factor-α inhibitor that treats autoimmune conditions including arthritis, plaque psoriasis, ankylosing spondylitis, and inflammatory bowel disease (IBD). With spending on Humira reaching $19.8 billion in 2020, US health plans have been anxious to join their counterparts in Europe, where the drug has seen biosimilar competition since in 2018.

Iceland’s national health plan required patients to switch from Humira to the Samsung Bioepis biosimilar, Imraldi, which had a different injection device and contained citrate, a chemical buffer used to maintain the medication’s stability. Now, a study published in Frontiers in Medicine shows that both factors prompted negative feedback from about half of the patients taking part in a telephone survey following the switch.

The Humira device is lighter and features an activator button on one end, which the user must press with a finger or thumb to administer the medication. The Imraldi device does not have a button and is injected directly.

Led by Kristin Karlsdottir, PhD, MEd, of Landspitali University Hospital, and Anna I. Gunnarsdottir, PharmD, of the School of Health Sciences, University of Iceland, both in Reykjavik, the study involved gathering a list of all patients treated through Landspitali University Hospital who had switched from Humira to Imraldi under the protocol and contacting them for a phone interview about their experience with the change. Of the patients contacted, 84.5% agreed to participate. The average age was 50.8 years, 53.5% were female, and 96% self-administered the drug.

The study uncovered an important difference in the education method for the Imraldi switch compared with how patients learned to use Humira. While 90.5% of the patients stated they had received individualized instruction in how to use the Humira pen when they started taking adalimumab, only 18.2% received similar lessons for the Imraldi pen. Instead, most relied upon a letter from the hospital with printed instructions, which told them to call a doctor or nurse if they needed additional help.

Results from the phone survey were as follows:

• Almost half (46.6%) found it more difficult to use the Imraldi pen than the Humira pen, while 12.5% found the Imraldi pen easier to use
• Differences in the experiences were due to more painful insertion of the needle (62.2%) and that the insertion process was different (63.0%); however, needles on both pens are the same length and thickness
• The authors reported that 62% of the patients did not feel any differences in grip of the 2 pens, but 23.5% of the patients thought the Imraldi grip was more difficult and 12.5% said the Humira grip was more difficult
• By disease type, patients with IBD were most likely to report a difference with Imraldi and to report this pen was more painful, followed by patients with arthritis
• Patients felt the needle insertion with the Imraldi pen caused a burning sensation “during and after the injection,” and some deliberatively prolonged the time between administration

These observations raise concerns about medication adherence, the authors wrote, and could be explained by the fact that the Imraldi injection contains more volume, including citrate (0.4 mL for Humira vs 0.8 mL for Imraldi). Because citrate had been removed from the Humira solution prior to the change to Imraldi, some patients told the investigators that “they perceived that they had returned to the ‘old’ Humira pen when they experienced this painful injection.”

The authors recommended that a more thorough, individualized education plan be part of any large-scale switch to a biosimilar medication that includes a delivery device. “Our results highlight the importance of thorough information, not only with an information letter but also with the possibilities for individualized introduction in planning switching to biosimilars,” they wrote.

Reference

Karlsdottir K, Gunnarsdottir AI, Grondal G, et al. A patients' perspective towards the injection devices for Humira and Imraldi in a nationwide switching program. Front Med. Published online January 27, 2022. doi:10.3389/fmed.2022.799494