Benzinga | Oct 26, 2020 08:15AM EDT

Kiniksa To Present New Data From Phase 2 Trial Of Mavrilimumab In Giant Cell Arteritis To Be Presented At Late-Breaking Abstracts Session Of American College Of Rheumatology Convergence 2020

- Mavrilimumab reduced time-to-flare and increased sustained remission in Phase 2 giant cell arteritis clinical trial -

- Primary and secondary efficacy endpoints achieved statistical significance -

- Results were consistent across new onset and relapsing/refractory cohorts -

HAMILTON, Bermuda, Oct. 26, 2020 (GLOBE NEWSWIRE) -- Kiniksa Pharmaceuticals, Ltd. (NASDAQ:KNSA) ("Kiniksa"), a biopharmaceutical company with a pipeline of assets designed to modulate immunological pathways across a spectrum of diseases, today announced that new data from the global Phase 2 clinical trial of mavrilimumab in giant cell arteritis (GCA) will be presented at the late-breaking abstracts session during the American College of Rheumatology (ACR) Convergence 2020. Mavrilimumab is an investigational fully-human monoclonal antibody that targets granulocyte macrophage colony stimulating factor receptor alpha (GM-CSFR?). Both the primary and secondary efficacy endpoints achieved statistical significance, and there was a consistent trend of efficacy across the new onset and relapsing/refractory cohorts.

"There is a significant unmet need for safe and effective giant cell arteritis therapies. We believe mavrilimumab, with its upstream inhibition of two immune pathways implicated in giant cell arteritis, has the potential to provide differentiation from current standard of care therapies by addressing the underlying pathophysiology of the disease," said John F. Paolini, MD, PhD, Chief Medical Officer of Kiniksa. "In the Phase 2 giant cell arteritis trial, mavrilimumab was superior to placebo on the primary and secondary efficacy endpoints of time-to-flare and sustained remission at Week 26. These data further underscore the potential for mavrilimumab to offer a differentiated treatment option for patients with both relapsing/refractory disease as well as new onset disease."

Dr. Maria Cid1, a co-principal investigator for the global Phase 2 trial, will deliver a virtual presentation entitled Mavrilimumab (anti GM-CSF receptor ? monoclonal antibody) Reduces Time to Flare and Increases Sustained Remission in a Phase 2 Trial of Patients with Giant Cell Arteritis at the late-breaking abstracts session (L06 - L11) on Monday, November 9, 2020 at 11:30 a.m. Eastern Time. Dr. Sebastian Unizony2 is a co-principal investigator.

The Phase 2 trial randomized 70 patients 3:2 to mavrilimumab 150 mg (N=42) or placebo (N=28) biweekly injected subcutaneously, co-administered with a protocol-defined 26-week oral corticosteroid taper. Patients were stratified by new onset (n=35) or relapsing/refractory (n=35) disease.

The primary efficacy endpoint of time-to-first adjudicated GCA flare by Week 26 in all treated patients was statistically significant (Hazard Ratio = 0.38, p=0.0263).

* Median time-to-flare by Week 26 could not be estimated in mavrilimumab recipients due to the low number of flares in the mavrilimumab treatment arm. The median time-to-flare for placebo recipients was 25.1 weeks.

* There was a 62% lower risk of flare in mavrilimumab recipients compared to placebo recipients.

The secondary efficacy endpoint of sustained remission at Week 26 in all treated patients was also statistically significant.

* The sustained remission rate at Week 26 was 33.3 percentage points higher in mavrilimumab recipients (83.2%) compared to placebo recipients (49.9%) (p=0.0038).

While the study was not powered for disease cohorts, there was a consistent trend of efficacy across the new onset and relapsing/refractory cohorts.

New Onset Cohort

* There was a 71% lower risk of flare in mavrilimumab recipients compared to placebo recipients (Hazard Ratio = 0.29, p=0.0873).

* The sustained remission rate at Week 26 was 28.9 percentage points higher in mavrilimumab recipients (91.3%) compared to placebo recipients (62.3%) (p=0.0727).

Relapsing/Refractory Cohort

* There was a 57% lower risk of flare in mavrilimumab recipients compared to placebo recipients (Hazard Ratio = 0.43, p=0.1231).

* The sustained remission rate at Week 26 was 30.6 percentage points higher in mavrilimumab recipients (72.2%) compared to placebo recipients (41.7%) (p=0.0668).

Mavrilimumab was well-tolerated; there were no drug-related serious adverse events, and the rates of drug-related treatment-emergent adverse events between mavrilimumab recipients and placebo recipients were similar.

The 12-week washout safety follow-up period is ongoing, and additional analyses of this Phase 2 trial are planned. Next steps for the development program in GCA will be further informed by anticipated discussions with the U.S. Food and Drug Administration (FDA).

The abstract is available through the ACR website.

Table 1 as submitted to ACR by the authors for publication and as referenced in the abstract follows below. The table was inadvertently omitted during the online posting of the abstract.