AbbVie designed and sponsored the trial and provided the medications. AbbVie is the manufacturer of upadacitinib.
Among the 1,704 patients, 429 received the 15 mg dose of upadacitinib, 423 received the 30 mg dose of upadacitinib, 423 received the placebo and 429 received adalimumab. Ninety-one percent of patients completed the trial through week 24. Demographic characteristics were similar among all patient groups.
By week 12, an ACR20 response was observed in 70.6% of patients who received the 15 mg dose of upadacitinib, compared with 78.5% who received the 30 mg dose. An ACR20 response was observed by week 12 in 36.2% of those receiving placebo and in 65% of those in the adalimumab group.
The results showed that both the 15 mg and 30 mg doses were non-inferior to adalimumab in achieving an ACR20 response at week 12, and the 30 mg upadacitinib dose, but not the 15 mg dose, was superior to adalimumab.
Compared with placebo, the upadacitinib results were better for other aspects of PsA, including objective measures of psoriatic activity, physical function and fatigue. Because of the trial results, certain end points comparing 15 mg of upadacitinib and adalimumab could not be analyzed, the study researchers write.
McInnes et al. found some differences in the number of adverse and serious adverse events, with more frequent occurrences among those receiving the 30 mg upadacitinib dose. An upper respiratory tract infection was the most common adverse event. Serious infections occurred in 1.2% of patients taking the 15 mg upadacitinib dose, 2.6% taking the 30 mg dose, 0.9% taking placebo and 0.7% taking adalimumab.
Through week 24, other infections included a case of Candida urethritis with the 15 mg dose and one case of Pneumocystis jirovecii pneumonia and cytomegalovirus with the 30 mg dose. Herpes zoster occurred in four patients receiving the 15 mg dose of upadacitinib, five receiving the 30 mg dose, three receiving placebo, and none among those receiving adalimumab. One pulmonary embolism occurred with the 30 mg dose.
Cancer was diagnosed in one patient in the 15 mg upadacitinib group (i.e., neuroendocrine carcinoma), one in the placebo group (i.e., basal cell carcinoma) and three patients each in the 30 mg and adalimumab groups. In the 30 mg group, two patients were diagnosed with basal cell carcinoma and one with a malignant lung neoplasm. In the adalimumab group, one patient was diagnosed with colon cancer, one with ovarian cancer and one with uterine cancer.
The percentage of patients with adverse events involving hepatic disorders was 9.1% in the 15 mg upadacitinib group, 12.3% in the 30 mg group, 3.8% in the placebo group and 15.6% in the adalimumab group.
Anemia and lymphopenia occurred with similar incident rates with the 15 mg upadacitinib and placebo doses, but more frequently with the 30 mg dose. One patient had a grade 3 decrease in their hemoglobin level and another a grade 3 decrease in their platelet count after stopping the 30 mg dose of upadacitinib. The 30 mg group also had a higher frequency in grade 3 decreases in neutrophil and lymphocyte levels.