MADRID – , Andrew Blauvelt, MD, reported at the annual congress of the European Academy of Dermatology and Venereology.
He presented a comprehensive analysis of safety data from all 49 clinical trials of the tumor necrosis factor inhibitor for its approved indications. The data set included 11,317 patients who received certolizumab for a collective 21,695 person-years in 27 trials in rheumatoid arthritis patients, 5 in psoriasis, 15 for Crohn’s disease, and one trial each for axial spondyloarthritis and psoriatic arthritis.
“It’s not real-world data, but it is a large group of patients [studied] over many years,” noted Dr. Blauvelt, a dermatologist and president of the Oregon Medical Research Center, Portland.
As a renowned authority on psoriasis, he was part of a multidisciplinary expert panel commissioned by UCB to analyze serious adverse events in the complete clinical trials experience involving the company’s tumor necrosis factor inhibitor certolizumab (Cimzia). The panel included experts from rheumatology, gastroenterology, epidemiology, and other disciplines.
The key takeaway: “When you think about the serious side effects of the drug, you have to think about what the indication is, whether the patients are on systemic corticosteroids, and whether they’re heavy or not,” Dr. Blauvelt said.
Take, for example, the risk of serious infections requiring treatment with intravenous antibiotics. The incidence rates ranged from a low of 1.5 per 100 patient-years in psoriasis patients on certolizumab to a high of 5.97 in those with Crohn’s disease, with rates of 3.44 cases per 100 patient-years among rheumatoid arthritis patients and 1.64-1.67 in those with psoriatic arthritis and ankylosing spondylitis, respectively. Patients with Crohn’s disease were 2.22-fold more likely than were those with rheumatoid arthritis to experience a serious infection during their clinical trial experience on certolizumab. In contrast, psoriasis patients had a 52% relative risk reduction and those with psoriatic arthritis were 31% less likely to develop a serious infection compared with those with rheumatoid arthritis.
The explanation for these highly variable serious infection rates lies in part on the huge differences in the concurrent use of systemic corticosteroids with certolizumab across indications. A mere 3.3% of psoriasis patients were also on steroids, compared with 46.2% of rheumatoid arthritis patients, 50.8% of those with ankylosing spondylitis, and about 25% of the Crohn’s disease and psoriatic arthritis patients, he noted.
Advanced age was independently associated with increased risk of serious infections. Patients aged 65 or older were 1.68-fold more likely to experience this event than were those under age 45. And patients whose disease duration was 10 years or more at baseline had a 1.36-fold increased serious infection risk compared with those who had less than a 1-year-long disease history, independent of which disease they had.
The prevalence of baseline obesity varied by indication. The mean body mass index was 30.1 kg/m2 in the psoriasis patients, 29.8 kg/m2 in those with psoriatic arthritis, lowest at 24 kg/m2 in Crohn’s disease patients, and a bit over 27 kg/m2 in those with rheumatoid arthritis or ankylosing spondylitis.
Obesity alone was not an independent risk factor for serious infection in certolizumab-treated patients; however, the combination of a BMI of 30 kg/m2 or more plus systemic corticosteroid use was associated with a greater risk than with steroids alone.
Based upon a multivariate regression analysis adjusted for age, sex, indication, disease duration, use of methotrexate, and prior use of other TNF inhibitors, the investigators calculated that in patients with Crohn’s disease 16.6% of serious infections in patients on certolizumab were attributable to systemic corticosteroid use.