Tofacitinib: New Study with Short Duration of Follow up Fails to Find Cancer Association

Are JAK inhibitors associated with cancer?

The Oral Surveillance study compared the risk of cancer in rheumatoid arthritis patients using tofacitinib compared to TNF inhibitors. The data showed a 48 % increased risk of cancer in RA patients 50 years of age and over who were using methotrexate. The FDA has required all JAK inhibitors to carry a boxed warning that JAK inhibitors may cause cancer – in addition to infections, heart disease, mortality and blood clots. It’s important for hair specialists to carefully follow the data about JAK inhibitors and cancer because we now use JAK inhibitors for treating many hair loss conditions.

Authors from Brigham and Women's Hospital & Harvard Medical School, Boston set out to examine the risk of cancer in rheumatoid arthritis (RA) patients using tofacitinib in the real-world setting. The authors used U.S. insurance claims data the authors created two cohorts of RA patients initiating treatment with tofacitinib or TNFI.

The first group consisted of patients 18 and over at cohort entry date. This was referred to by authors as a real world cohort. The second group was known as the RCT-duplicate cohort and  this group tried to mimic the ORAL Surveillance trial. For example, it was restricted to patients 50 years (65 in Medicare) of age or older, with at least one methotrexate dispensation in six months prior to cohort entry date, and at least one cardiovascular risk factor (including history of smoking, hypertension, dyslipidemia, diabetes mellitus, ischemic heart disease, or family history of ischemic heart disease) in the year prior to cohort entry date.

There were 83,295 patients of whom 10,504 (12.6%) initiated tofacitinib.

The mean age of patients in the two groups was similar. There were no discernable differences across most comorbidities, prior prescriptions, and markers for healthcare utilization when comparing tofacitinib initiators with TNFI initiators. The pooled weighted HR (95% CI) for the primary any malignancy outcome associated with tofacitinib compared with TNFI was 1.01 (0.83, 1.22) in the one cohort and 1.17 (0.85, 1.62) in a second cohort  

Conclusions and Comments

Overall, the authors did not  find evidence for an increased risk of malignancy with tofacitinib, in comparison with TNFI, in RA patients treated in the real-world setting. It should be noted here that the follow-up time was relatively short (mean duration of follow-up was short <1 year). Despite this, there were some 9,237 patients (11.1% of the study population) had a follow-up time of at least two years. The authors point out that they cannot rule out a possibility of an increase in risk that may accrue with a longer treatment duration.

REFERENCE

Farzin Khosrow-Khavar et al. Tofacitinib and risk of malignancy: results from the Safety of TofAcitinib in Routine care patients with Rheumatoid Arthritis (STAR-RA) Study. Arthritis Rheumatol . 2022 May 29.