AstraZeneca is betting that Ionis’ second drug for transthyretin amyloidosis, or ATTR, will stand out where its first one couldn’t.
Ionis developed Tegsedi for years with GlaxoSmithKline. But the pharma company passed on an option to acquire the drug in 2017 after worrisome side effects emerged in a Phase 3 trial. A rival medicine from Alnylam Pharmaceuticals called Onpattro, which didn’t have those same safety concerns, reached the U.S. market before.
Though Tegsedi was approved by the Food and Drug Administration shortly afterwards, it hasn’t sold as well as Onpattro. The drug’s disappointing performance was one or the reasons Ionis chose to acquire and restructure Akcea Therapeutics, a former spin-out tasked with selling Tegsedi and some other Ionis medicines. Tegsedi is now largely sold by Swedish firm Sobi.
Ionis has been hoping for better luck with eplontersen, a second-generation version of Tegsedi that is meant to be more precise and address a greater portion of the population with ATTR. Unlike Tegsedi, eplontersen is meant for people with both inherited and acquired forms of the disease, whereas Tegsedi treats only the former group. Tegsedi is also only approved for ATTR patients with nerve damage, whereas eplontersen is in late-stage testing for those with heart damage as well.
Ionis could face greater competition, however, as the treatment options for ATTR are changing fast. (For years, liver transplants and a generic drug called diflunisal were the only available therapies.) Following the approvals of Tegsedi and Onpattro, Pfizer’s Vyndamax, which is similar to diflunisal, was cleared for ATTR patients with heart problems. Another oral medicine, from BridgeBio, is in late-stage testing, as is a next-generation Alnylam drug meant to be more convenient and longer lasting than Onpattro.
A gene editing drug from Intellia Therapeutics has also shown promise in early testing. And Novo Nordisk recently acquired a drug from Prothena that, like eplontersen, is meant for both inherited and acquired forms of ATTR.
For AstraZeneca, the deal adds to its growing focus on rare disease drugs, and amyloidosis specifically. AstraZeneca completed its nearly $40 billion acquisition of Alexion Pharmaceuticals in July and, a few months later, bought Caelum Biosciences, which is making a drug for a different type of amyloidosis.
The deal with Ionis gives AstraZeneca partial U.S. rights to Ionis’ drug and full ownership elsewhere.
Ionis expects Phase 3 results in ATTR patients with nerve damage in the middle of 2022 and, if successful, could file for approval by the end of next year.