AxSpA trial details
In the axSpA trial, called INVIGORATE-1, researchers recruited people aged ≥18 years with a diagnosis of active radiographic axSpA according to modified New York criteria or nonradiographic axSpA according to ASAS criteria, and all had inflammatory back pain for ≥6 months with an onset before age 45. They were randomized at a 1:1 ratio to receive IV secukinumab (6 mg/kg loading dose, followed by 3 mg/kg every 4 weeks) or placebo for 16 weeks. At that point, the placebo group switched to the same monthly doses of IV secukinumab.
Participants had a mean age of about 39, and about one-third were female.
Following the statistical superiority in ASAS 40 response rates seen with IV secukinumab at week 16, patients who from there switched from placebo to IV secukinumab achieved comparable ASAS 40 response rates to those of patients originally randomized to secukinumab by week 24, reaching 66.8% for those on secukinumab the whole time and 74.9% for those who switched.
Secondary outcome measures were similar in both groups at week 52.
Among all patients who took secukinumab – the percentage with any adverse event was 63.2%, and 6% had a nonfatal adverse event deemed serious. There was one death during secukinumab treatment not suspected to be related to treatment.
In a presentation about the axSpA study findings, Atul Deodhar, MD, of Oregon Health & Science University, noted that “having an IV biologic available in the U.S. has some advantages. There are certain insurance providers such as Medicare where it is more economical for the patient to have an IV drug available.”
Dr. Deodhar also noted that in October the FDA approved a recommended lower dose for the IV treatment than in the study: 1.75 mg/kg instead of 3 mg/kg following the loading dose. That’s because the 3 mg/kg dose caused blood levels to be higher than those in the subcutaneous form, he said.
The FDA made the same dose recommendation for PsA.
Study limitations
Dr. Goodson, the U.K. consultant rheumatologist, noted a limitation of the trials: “It would have been interesting to compare IV to subcutaneous route secukinumab.” Still, the findings suggest that “the safety and efficacy of IV administration appears comparable,” she said.
“IV administration will have associated costs of attending hospital or infusion clinics,” she added, “and the cost of additional staff and administration need to be considered.”
Novartis, the maker of secukinumab, funded both studies. The PsA study authors report multiple relationships with industry, and some, such as Dr. Kivitz, have connections to Novartis. The axSpA study authors also report multiple relationships with industry, and some, such as Dr. Deodhar, have connections to Novartis. Some authors of both studies are Novartis employees. Dr. Goodson disclosed financial relationships with UCB and AbbVie.