Novo Nordisk will advance its acquired ATTR amyloidosis with cardiomyopathy monoclonal antibody (mAb) to Phase III trials.
The Danish pharma said that the Phase II trial of coramitug (PRX004), an mAb designed to deplete amyloid deposits, was “successfully completed”.
The trial investigated the efficacy and safety of once-monthly intravenous (IV) doses of coramitug compared to placebo in 105 patients with ATTR-cardiomyopathy.
The primary endpoints of the trial included the functional endpoints of a six-minute walking test (6MWT), as well as a change in NT-proBNP after 52 weeks of treatment.
While data has not yet been released, Novo Nordisk said results will be available at a medical conference later this year. However, the drugmaker confirmed its intention to initiate a Phase III trial of the drug in ATTR with cardiomyopathy before the end of 2025 in its Q2 2025 earnings call on 6 August.
The news will be a welcome financial development for Prothena Corporation after the drug was acquired from them by Novo Nordisk in July 2021.
Under the agreement, Prothena is eligible to receive up to $1.2bn upon achievement of clinical development and sales milestones, including the $100m earned to date.
While NovoNordisk stocks have dropped on 6 August, in part due to the Q2 and H1 earnings announcement, Prothena’s stock has risen slightly on the news, up from $7.03 at market close on 5 August to $7.45 at market open on 6 August – a 5.97% rise.
Prothena’s CEO Dr Gene Kinney said: “We are excited by Novo Nordisk’s decision to advance coramitug into Phase III development. There remains a significant unmet need in patients with ATTR amyloidosis with cardiomyopathy, who are at high risk for early mortality and significant morbidity due to amyloid deposition in vital organs.”
ATTR successes and failures
In May 2025, Prothena faced a trial setback after a Phase III study of birtamimab in patients with amyloid light-chain (AL) amyloidosis missed its primary endpoint.
During the same month, Intellia Therapeutics’ stock crashed after a serious adverse event (AE) in a Phase III trial of its ATTR cardiomyopathy gene therapy. Despite this event, trials of the therapy are ongoing.
US biopharma Alnylam is celebrating a recent win, however, after its ATTR cardiomyopathy drug Amvuttra (vutrisiran) gained approval by the European Commission on 11 June. This came three months after the therapy got the green light from the US Food and Drug Administration (FDA) in March 2025.
Other approved therapies include Pfizer’s Vyndamax (tafamidis) and BridgeBio Pharma’s Attruby (acoramidis).
After the EC approval of Amvuttra, GlobalData cardiovascular and metabolic diseases analyst Costanza Alciati said the approval marked a change in the treatment paradigm for these patients, with therapies such as coramitug and ALXN2220 also set to have an impact.
