Ustekinumab, a human interleukin-12 and -23 antagonist, has been approved for the treatment of adults with active psoriatic arthritis, the manufacturer has announced.
The approved indication is for use alone or in combination with methotrexate, in the form of a 45-mg subcutaneous injection at weeks 0 and 4, and then every 12 weeks. For patients with coexistent moderate-to-severe plaque psoriasis who weigh more than 220 pounds, the recommended dose is a 90-mg subcutaneous injection at weeks 0 and 4, and then every 12 weeks.
Ustekinumab, approved for treating psoriasis in 2009, is marketed as Stelara by Janssen Biotech, which announced the approval in a press release on Sept. 23. Ustekinumab is the first treatment targeting the cytokines interleukin-12 and interleukin-23, according to the statement.
Approval was based on the results of two phase III multicenter, randomized double-blind studies comparing ustekinumab to placebo in 927 patients with active psoriatic arthritis, with at least five tender and five swollen joints and a C-reactive protein (CRP) level of at least 0.3 mg/dL, despite previous treatment with conventional therapy. The primary endpoint was the ACR 20 response at 24 weeks.
In the first trial, PSUMMIT 1, 42% of those on the 45-mg dose and 50% of those on the 90-mg dose achieved an ACR 20 at 24 weeks, vs. 23% of those on placebo. In addition, 57% of those on the 45-mg dose and 62% of those on the 90-mg dose achieved a PASI (Psoriasis Area and Severity Index) 75 response, vs. 11% of those on placebo.
In the second study, PSUMMIT II, 44% of those on a 45-mg dose and 44% of those on a 90-mg dose met the primary endpoint, vs 20% of those on placebo. Also, 51% of those on the 45-mg dose and 56% of those on the 90-mg dose achieved a PASI 75 response, vs. 5% of those on placebo.
The results of the PSUMMIT 1 study were published online in the Lancet on June 13 (doi:10.1016/S0140-6736[13]60594-2).
The warnings and precautions section of the ustekinumab label includes information about the risk of serious infections and other risks associated with treatment.
The updated label is available here.