Baricitinib shows promise in systemic lupus erythematosus
medwireNews: The addition of once-daily baricitinib to standard background therapy could improve clinical outcomes in patients with systemic lupus erythematosus (SLE), phase II trial findings show.
Presenting the findings at the EULAR 2018 meeting in Amsterdam, the Netherlands, Daniel Wallace (Cedars-Sinai Medical Center, Los Angeles, USA) reported that 67% of 104 patients receiving the oral selective Janus kinase (JAK) 1 and 2 inhibitor baricitinib 4 mg achieved resolution of arthritis or rash, according to the SLE disease activity index 2000 (SLEDAI-2K), arthritis at week 24. This compared with 53% of 105 patients given placebo, giving a significant difference.
Baricitinib treatment was also associated with a significant improvement in the secondary endpoint, Wallace noted, with 64.4% of patients taking baricitinib achieving an SLE responder Index (SRI) response, compared with 47.6% of placebo-treated patients.
A smaller proportion of baricitinib- than placebo-treated patients had flare of any severity or severe flare on the SELENA-SLEDAI Flare Index (33 vs 51% and 6 vs 11%), and more were in a Lupus Low Disease Activity State (LLDAS; 38 vs 26%), and had a greater reduction in tender joint count (6.9 vs 5.6 points).
There was also a group of 105 patients who took baricitinib at a daily dose of 2 mg, and while greater improvements were seen in this group compared with the placebo group, the differences were not significant.
More patients in the baricitinib arms than the placebo arm experienced adverse events leading to treatment discontinuation (73.1 vs 64.8%) and serious adverse events (9.6 vs 4.8%), but Wallace said the “safety and tolerability and tolerability profile of baricitinib remained satisfactory.”
There were no deaths, malignancies, major adverse cardiovascular events, tuberculosis, or serious herpes zoster infections.
Commenting on the safety aspect of the findings in a press briefing, Thomas Dörner (Charité University Hospitals, Berlin) noted that cases of serious infections while numerically higher with baricitinib than placebo, at 5.8% versus 1.0%, were within the range expected for SLE patients.
He also pointed out that “herpes zoster is very often reactivated in [SLE] patients by the disease but also by the immunosuppressant therapy and most notably herpes zoster was only seen in one patient in the placebo group and in one patient in the high-dose baricitinib group.”
Another potential concern, raised by the US FDA and which led to only the 2 mg dose being approved for rheumatoid arthritis (RA), was the risk for deep vein thrombosis (DVT) but this occurred in only one patient in the high-dose baricitinib group, and this was a patient with additional risk factors.
“We would have expected a much higher frequency of DVTs in this population,” he said.
Dörner summarized the findings, saying: “I think this is now a very promising outlook that, at least for the 4 mg [baricitinib dose], there is very interesting improvement in terms of skin and joint, there have been no new safety or tolerability issues as what we know from the RA population, and we are looking forward to seeing subsequent studies with regards to baricitinib in this population where we have a need for additional and more efficacious therapies.”
By Lucy Piper
medwireNews is an independent medical news service provided by Springer Healthcare. © 2018 Springer Healthcare part of the Springer Nature group