Kiniksa Pharmaceuticals is stopping development of a midphase autoimmune asset and returning a drug candidate to AstraZeneca as it doubles down on its cardiovascular disease pipeline.
The asset licensed from AstraZeneca, GM-CSF antagonist mavrilimumab, was already on the back-burner, but the termination of the midphase autoimmune program comes as more of a shock. Six weeks ago, Kiniksa chief medical officer John Paolini, M.D., told investors the company was “certainly very excited” about a phase 2b trial of abiprubart in Sjögren’s syndrome. Today, Kiniksa said it is stopping the study.
Kiniksa, which is evaluating strategic alternatives for abiprubart, framed the decision to end the trial as a result of a “strategic reprioritization of its portfolio and certain capital allocation considerations.” The action will cost $33 million to $37 million, Kiniksa said, but will free the biotech from the cost of funding a study that was scheduled to run into 2027.
Abiprubart, an antibody that inhibits the signaling between CD40 and CD154, was in development in a competitive niche but Kiniksa had previously presented that as a positive. Last month, Kiniksa CEO Sanj Patel told investors “there has been some external derisking of the mechanism through other assets,” but he said abiprubart was differentiated through its monthly subcutaneous dosing.
Amgen’s CD40L antagonist fusion protein, dazodalibep, is ahead of abiprubart in the race to market, with the big biotech starting phase 3 trials in Sjögren’s last year. But that drug is given intravenously.
The high-concentration liquid formulation of abiprubart opened up the option of subcutaneous dosing.
The list of rivals that Kiniksa believed may be able to offer subcutaneous dosing has thinned in recent years. Novartis axed its rival subcutaneous anti-CD40 antibody in Sjögren’s last month after assessing the risks and benefits of the molecule. Sanofi reached a similar decision in April, when it crossed Sjögren’s off the list of potential indications for its anti-CD40L prospect. Bristol Myers Squibb terminated a phase 1 trial of its CD40 candidate in Sjögren’s in 2023 because of “insufficient enrollment.”
Kiniksa disclosed the winddown of its Sjögren’s trial, which it expects to complete by the end of the year, alongside the news that it is terminating development of mavrilimumab. The biotech licensed the asset from AstraZeneca’s MedImmune in 2017, paying $23 million in upfront and subsequent payments. But by early last year, the company was evaluating potential partnership opportunities to advance the molecule.
The hunt for a partner ended last week, when Kiniksa told MedImmune it was stopping development of the asset and terminating the license agreement.
Kiniksa’s actions leave it focused on a cardiovascular disease pipeline led by the IL-1 antagonist KPL-387. The program is targeting recurrent pericarditis, the same indication as Kiniksa’s approved drug Arcalyst, and a phase 2/3 trial is set to start this year.