Conference Coverage
Malignancy risk of tocilizumab and TNF inhibitors found similar
AMSTERDAM – In a cohort study, no difference was found for cancer risk following treatment of rheumatoid arthritis with the IL-6 inhibitor...
AMSTERDAM – Patients treated with a tumor necrosis factor inhibitor for any indication had their mortality rate cut by about one third, compared with the general population, in a combined analysis of safety findings from 78 trials that involved nearly 30,000 patients.
This first indication that treatment with a tumor necrosis factor inhibitor (TNFi) significantly cut overall mortality only became apparent because of the very large number of patients and patient-years of treatment analyzed, and is likely a real effect – not an artifact – that’s probably linked in part to the anti-inflammatory effect from treatment and its favorable impact on cardiovascular disease events, Gerd R. Burmester, MD, said at the European Congress of Rheumatology.
The cut in overall mortality might also partially result from a “healthy cohort effect,” in which patients enrolled in trials pay more attention to their diet and other aspects of a healthy lifestyle, compared with the general population. But Dr. Burmester cited the recent results from the CANTOS trial that showed treatment with the anti-inflammatory drug canakinumab (Ilaris) was linked with a significant 12% relative reduction in cardiovascular death, myocardial infarction, and stroke (New Engl J Med. 2017 Sept 21;377[12]:1119-31).
“It may be that the anticytokine effect of TNFi works the same way as canakinumab,” Dr. Burmester said in an interview.
The results also confirmed previous reports, based on trial data from fewer numbers of TNFi-treated patients, of low rates of serious infections and malignancies, said Dr. Burmester, professor and director of the department of rheumatology and clinical immunology at Charité Medical University in Berlin.
The data he presented came from both randomized trials and open-label studies of adalimumab (Humira) conducted in several countries worldwide through the end of 2016. The various studies enrolled a total of 29,987 patients treated with adalimumab for 56,951 patient-years who had any of 11 different diseases, including rheumatologic, gastrointestinal, and dermatologic diseases. The most common condition treated in the studies was rheumatoid arthritis (in 33 of the 78 studies), followed by psoriasis (13 studies), and Crohn’s disease (11 studies).
The studies included 9,363 patients treated for at least 2 years, and 4,003 patients treated for at least 5 years. The median duration of adalimumab exposure was 0.7 years and the maximum exposure was just over 12 years.
The overall rate of serious infections in treated patients was 3.7 per 100 patient-years. The most common serious infections were pneumonia, at a rate of 0.6 per 100 patient-years, followed by cellulitis, at a rate of 0.2 per 100 patient-years. Active tuberculosis infections also occurred at a rate of 0.2 per 100 patient-years. Malignancies occurred at a rate of 0.6 per 100 patient-years. These rates were similar to those reported by Dr. Burmester and his associates in 2013 using data from a small pool of patients – 23,458 – enrolled in 71 studies of adalimumab (Ann Rheum Dis. 2013 Apr;72[4]:517-24).
In the current study, Dr. Burmester and his coauthors analyzed the observed mortality rate of the adalimumab-treated patients against the mortality rates for the general populations in the various countries in which the studies were run, based on World Health Organization statistics for the period 1997-2006, and adjusted so that the age and sex of the comparison general populations matched the age and sex of the treated patients. This analysis showed an overall, statistically significant mortality reduction in patients receiving adalimumab of 35%, which was consistent in both the subgroups of men and women.
The observed mortality reduction linked with TNFi treatment is likely a class effect, Dr. Burmester said, although similar analyses have not been conducted using data from patients treated with other TNFis. So far, he has been unsuccessful in getting similar, large-scale trial data from manufacturers of other TNFis that he has approached, but Dr. Burmester said he hopes to eventually receive these data so that he can perform an even larger analysis.
The study was sponsored by AbbVie, the company that markets adalimumab (Humira). Dr. Burmester has been a consultant to and speaker on behalf of AbbVie, as well as for Bristol Myers Squibb, Merk, Pfizer, Roche, and UCB.
SOURCE: Burmester GR et al. Ann Rheum Dis. 2018;77(Suppl 2):165. Abstract OP0233.