Integrated 10-year analysis confirms safety profile abatacept

The development of malignancy may be linked to the use of immunomodulators. Data suggests that the risks of overall, breast, or lung malignancies are not significantly increased in patients treated with abatacept [1]. These findings are consistent with the established safety profile of abatacept.

Patients with rheumatoid arthritis (RA) are at an increased risk of malignancies compared with the general population [2]. Abatacept is a biologic immune modulator for RA, selectively blocking the specific interaction of CD80/CD86 receptors to CD28 and, therefore, inhibiting T cell proliferation and B cell immunological response. Abatacept has demonstrated efficacy and safety in the treatment of RA. “We have observed that, in clinical trial data, malignancy rates are similar for abatacept compared with placebo-treated patients and that post-marketing observational studies are valuable to assess the long-term risk associated with the medication,” said Dr Teresa Simon (Bristol-Myers Squibb, USA). The prospective cohort study aimed to assess the risk of solid tumour malignancies in RA patients treated with abatacept versus conventional synthetic disease-modifying drugs (csDMARDs) and other biologics or targeted synthetic DMARDs.

Four cohorts of data were analysed: the Swedish Anti-Rheumatic Therapy Registry (ARTIS), the German Registry for Rheumatoid Arthritis Observation of Biological Therapy (RABBIT), a disease registry (FORWARD; The National Databank for Rheumatic Diseases in the USA) and a healthcare claims database (the population-based British Columbia Canadian RA Cohort). “This analysis represents the largest safety study of abatacept treatment to date,” said Dr Simon. A total of 2,653 patients treated with abatacept and 1,485 given placebo were included. Seven trials used intravenous abatacept and two used the subcutaneous form. The outcomes were prespecified and agreed upon by the health authorities and they included overall malignancy, breast cancer, lung cancer, and lymphoma. The baseline data, rates, and summarised statistics were provided by the individual registries and databases. Complex multivariate analysis was performed by the individual registries and estimated adjusted rate ratios were provided.

The majority of patients were female (71% to 86%), with an approximate age of 55-63 years old. A history of malignancy was found in 4-34% of the patients. A greater number of abatacept-treated patients had been treated with ≥2 prior biologics (abatacept, 44 to 85%; csDMARDs, 11% [FORWARD] and other biological/targeted syntetic DMARDs, 0 to 19%). The incidence rate of overall malignancy in abatacept-treated patients was low (see Table). For all drugs, adjusted rate ratios showed no increased risk in overall malignancy. Individual registries showed a small increase in the breast (Canada), lung (Germany), and lymphoma (Sweden) cancers in abatacept-treated patients, but numbers were too low to assess relative risk. Given that blockade of the CTLA-4 pathway with resultant immune stimulation is an integral component of cancer immune checkpoint inhibition strategies in oncology, it is reassuring that suppression of this pathway is not linked to emergent cancer.

Table: Incidence rates for malignancies per 1,000 patient-years



 

1. Simon T, et al. Abstract OP0226. EULAR 2019
2. Simon TA, et al. Arthritis Res Ther. 2015 Aug 15;17:212

Posted on 4 September 201923 April 2024