AstraZeneca and Ionis Pharmaceuticals have signed an agreement to develop and market experimental therapy, eplontersen, previously called IONIS-TTR-LRX.

Eplontersen is a ligand-conjugated antisense treatment that can potentially lower the transthyretin (TTR protein) production for treating TTR amyloidosis’ (ATTR) hereditary and non-hereditary forms.

According to the deal, the parties will co-develop and co-market eplontersen in the US while AstraZeneca will handle the development and marketing activities globally, with the exception of Latin America.

Ionis is entitled to receive $200m in upfront payments and up to $485m as further conditional payments from AstraZeneca on obtaining regulatory approvals.

Furthermore, Ionis is eligible to get up to $2.9bn as sales-based milestone payments and low double-digit royalty payments based on the territory.

Under the agreement, Ionis will continue to produce and distribute eplontersen for clinical trials that are underway and for process qualifications.

AstraZeneca will oversee the commercial distribution of the antisense therapy with changeover timing decided by the companies. The company will also handle the product sales.

Subject to necessary closing conditions and regulatory approvals, the deal is anticipated to conclude in the fourth quarter of this year.

AstraZeneca BioPharmaceuticals R&D executive vice-president Mene Pangalos said: “Eplontersen has the potential to halt the progression of TTR-mediated amyloidosis, irrespective of whether it’s caused by genetic mutations or ageing.

“Thanks to its precise liver-targeting properties, it also has the potential to be a best-in-class treatment for patients suffering from this devastating disease and who currently have limited options.”

Eplontersen is presently being analysed in Phase III clinical trials to treat amyloid transthyretin cardiomyopathy (ATTR-CM) and amyloid transthyretin polyneuropathy (ATTR-PN).

In February 2018, AstraZeneca obtained a licence to a Generation 2.5 antisense drug from Ionis for the treatment of kidney disease.