Bayer's asundexian starts EU review for ischaemic stroke

Bayer's oral Factor XIa inhibitor asundexian is now under regulatory review by the EMA for secondary prevention of ischaemic stroke, keeping its nose ahead of main rival milvexian, from Bristol Myers Squibb and Johnson & Johnson.

The EU regulator is reviewing asundexian for the prevention of ischemic stroke in adults after a non-cardioembolic ischaemic stroke, or a high-risk transient ischaemic attack (TIA), based on the results of the pivotal OCEANIC-STROKE study.

The trial showed that adding asundexian to standard antiplatelet therapy used in these patients achieved a 26% fall in the risk of a secondary stroke compared to placebo, with no increase in the risk of major bleeding complications, which are a perennial concern for anti-clotting therapies.

The drug was also able to reduce the risk of a composite endpoint of cardiovascular death, myocardial infarction (MI), or stroke, as well as death from any cause, MI, or stroke.

BMS and J&J are also testing milvexian for a similar secondary stroke prevention indication in the LIBREXIA-STROKE trial, which is due to generate results later this year, and that timeline gives Bayer a shot at bringing the first drug in the class to market.

Stroke is a growing public health issue, affecting around 10 million people in Europe who are living with the consequences of stroke, with more than a million new cases each year, according to Bayer. It is the second leading cause of death globally, imposing a substantial burden on healthcare systems, with estimated global costs of $891 billion per year.

Despite current secondary prevention options like aspirin and clopidogrel, one in five patients having an ischaemic stroke will have another within the next five years, with the risk of death rising sharply the second time around.

"Between 2010 and 2019, the prevalence of ischaemic stroke and stroke-related mortality increased by 4% and 7%, respectively, across EU member states, underscoring the growing burden of this disease," said Christian Rommel, Bayer's global head of pharma R&D.

"The acceptance of our marketing authorisation application by the EMA is a testament to our unwavering commitment to offering patients in need novel treatment options," he added.

Bayer did not fare so well in its attempt to develop asundexian for atrial fibrillation, where it failed a phase 3 trial, so there is much anticipation to see if milvexian can fare better in the ongoing LIBREXIA-AF study, which could have topline results later this year.

Milvexian also has a failed pivotal trial on its record – LIBREXIA-ACS in acute coronary syndrome – but, despite that, BMS and J&J have insisted their drug retains the potential to make "multibillion-dollar" peak sales across its two remaining indications.

Asundexian is an important drug for Bayer as it contends with the loss of patent protection for J&J-partnered oral Factor Xa inhibitor Xarelto (rivaroxaban), which slashed its revenues from the drug by a third to $2.6 billion in 2025. A similar decline is expected this year.