Phase III RHAPSODY trial of rilonacept meets endpoints in pericarditis.- Kiniksa Pharma

Kiniksa Pharmaceuticals announced that the Phase III RHAPSODY trial showed that rilonacept achieved its primary and all major secondary efficacy endpoints in patients with recurrent pericarditis. Results show that prespecified primary and all major secondary efficacy endpoints were highly statistically significant.

The primary efficacy endpoint of median time-to-first adjudicated pericarditis recurrence in the randomized withdrawal period was highly statistically significant. Median [95% CI] time to pericarditis recurrence for rilonacept recipients in the randomized withdrawal period could not be estimated due to the low number of recurrences in the rilonacept treatment arm. The median time-to-recurrence for placebo recipients was 8.6 [4.0-11.7] weeks (Hazard Ratio = 0.04, p<0.0001). Rilonacept recipients experienced a 96% reduction in risk of recurrent pericarditis events. All major secondary efficacy endpoints in the randomized withdrawal period were also highly statistically significant.

Data shows that 81% of rilonacept recipients maintained clinical response at Week 16 of the randomized withdrawal period, compared to 20% of placebo recipients (p=0.0002). Consistent results were observed at Week 8 and Week 24 and were also highly statistically significant (p<0.0001 and p=0.0022, respectively). The proportion of rilonacept recipients with absent or minimal pericarditis symptoms at Week 16 of the randomized withdrawal period was 81% compared to 25% for placebo recipients (p=0.0006). Consistent results were observed at Week 8 and Week 24 and were also highly statistically significant (p<0.0001 and p=0.0002, respectively).

In addition, rilonacept recipients experienced no or minimal pain for 95% of trial days through Week 16 compared to 47% of trial days for placebo recipients (p<0.0001). Consistent results were observed at Weeks 8 and 24 and were also highly significant (p<0.0001 and p<0.0001, respectively). Patients are continuing to receive open label rilonacept in the Long-Term Extension. Rilonacept was well-tolerated, with a safety profile consistent with the existing ARCALYST label. Based on the Phase III RHAPSODY data, Kiniksa plans to submit an sBLA with the FDA later this year.