Impact of pain associated with the subcutaneous administration of adalimumab

There is limited information regarding the impact of patients' perception of injection pain on adherence to treatments, specifically in inflammatory bowel disease (IBD) patients. Therefore, we aimed to determine the impact of the pain associated with the subcutaneous administration of adalimumab in patients with IBD treated with the old formulation and the new low-volume/citrate-free formulation.

A specifically-designed questionnaire was completed by 76 patients with IBD, who started treatment with adalimumab before the availability of the low-volume/citrate-free formulation and were switched to this new formulation. Intensity of pain was measured by using visual analog scales (VAS).

A total of 62 patients (82%) experienced injection-related pain with the initial formulation. The perception of pain was associated with a decreased adherence to the treatment (37%), an increase in pre-administration anxiety (25%) or, as a consequence, the patient required someone else to carry out the injection (21%). Younger age was the only factor associated with pain perception. After switching to the new formulation, perception of pain persisted only in 2 patients (3%). Among those who felt pain with the initial formulation, pre-administration anxiety disappeared in 44%; 32% and 42% stated that the new formulation eased adherence and self-administration.

The perception of pain related to the subcutaneous administration of therapy negatively impacts on treatment adherence in IBD patients. Improved formulations for subcutaneous administration of drugs can positively impact patients' convenience and adherence.