For patients with rheumatoid arthritis (RA) being treated with tofacitinib, lymphoma rates are stable over time, and there are only minimal differences in the characteristics of patients with and without lymphoma, according to results published online in Arthritis Care & Research.
The researchers identified lymphoma events from 19 tofacitinib studies (2 phase 1, 9 phase 2, 6 phase 3, and 2 long-term extension). In these studies, participants with moderate to severe RA received tofacitinib 1 to 30 mg twice daily or 20 mg once daily as monotherapy or in combination with conventional synthetic disease-modifying antirheumatic drugs. The researchers sought to determine lymphoma incidence rates (number of patients with events/100 patient-years) and standardized incidence ratios.
Overall, 6194 participants received tofacitinib for a total of 19,406 patient-years of exposure. A total of 19 lymphomas occurred (incidence rate 0.10;95% CI, 0.06-0.15), with no increase observed with time of exposure.
After adjusting for age and sex, the standardized incidence ratio for lymphoma was 2.62 (95% CI, 1.58-4.09).
The clinical characteristics of the 19 lymphomas were typical of those that occur in people with RA.
The studies included in this analysis were funded by Pfizer Inc. This analysis was conceived by the Pfizer Inc. authors in collaboration with the academic authors. Medical writing support under the guidance of the authors was provided by Daniel Binks, PhD, of Complete Medical Communications, and was funded by Pfizer Inc. All authors were involved in interpreting the data and in drafting, reviewing, and developing the manuscript. Publication of this article was not contingent upon approval by Pfizer Inc.
Mariette X, Chen C, Biswas P, Kwok K, Boy MG. Lymphoma in the tofacitinib rheumatoid arthritis clinical development program. [published online April 2, 2018] Arthritis Care Res. doi:10.1002/acr.23421