Rilonacept Doesn't Dampen Pain Well in Gouty Arthritis

NSAIDs or colchicines may control gout flares, but not very effectively (pain drops by only about 50% within three days with either therapy) and at the risk of adverse effects. Hopes were pinned on the interleukin blocker rilonacept, after Phase 3 clinical trials showed that it heads off gout flares at the start of therapy. However, a new multicenter controlled trial finds that it does not provide significant relief, either on its own or as an add-on therapy to indomethacin.

The trial involved nearly 200 primary gout patients with an acute flare in the previous 48 hours, stratified by pain scores in the primary (index) gouty joint and assessed for swelling and tenderness.  The primary endpoint was self-reported pain in the index joint over 72 hours.

Subject were randomized to 3 groups: (1) subcutaneous rilonacept 320 mg at baseline plus oral indomethacin 150 mg/day tapering to 75 mg/day; (2) subcutaneous placebo plus indomethacin on the same schedule as in the first group; and (3) subcutaneous rilonacept as in the first group plus oral placebo on the same schedule as the indomethacin.

All treatment groups had significant reductions in pain scores from baseline when averaged at 24, 48 and 72 hours, with rilonacept producing earlier pain reductions. However, rilonacept plus indomethacin was not significantly better at reducing pain than indomethacin alone. A separate ad hoc analysis significantly favored indomethacin monotherapy.

Without comparison to placebo alone, NSAIDs, or colchicines, the researchers say, the clinical significance of these results is uncertain. There were similar numbers of adverse events in each group and one death, judged unrelated to rilonacept.