* Brilinta fails to show benefit over clopidogrel in PAD
* Follows failure of heart drug in stroke trial in March
* Drugmaker sells rights to Toprol-XL for up to $223 mln (Adds sales forecasts, detail on Toprol-XL deal with Aralez)
By Ben Hirschler
LONDON, Oct 4 (Reuters) - AstraZeneca's heart drug Brilinta has failed to help patients with serious circulatory problems in their legs, dealing a blow to a medicine that the company has tipped as a potential $3.5 billion-a-year seller by 2023.
AstraZeneca said on Tuesday that Brilinta failed to show a benefit over the older blood thinner clopidogrel in treating peripheral artery disease (PAD) in a large-scale clinical trial. PAD usually affects the legs.
Clopidogrel is the generic name of Sanofi's former blockbuster drug Plavix, which is now off patent.
The setback follows similar disappointing results in March with the same AstraZeneca pill in another big trial in stroke patients. Both studies were designed to open up new markets for Brilinta beyond its current use in heart attack patients.
Sean Bohen, AstraZeneca's head of global medicines development and chief medical officer, said he was disappointed that the so-called EUCLID trial had failed but added: "The proven benefits of Brilinta in acute coronary syndrome and post-myocardial infarction (heart attack) patients are established and remain unchanged."
Full results from the EUCLID trial, which involved 13,885 patients, are expected to be presented at the American Heart Association annual meeting in New Orleans in November.
A positive result could have boosted consensus forecasts for Brilinta, which currently stand at an annual $2.1 billion for 2021, according to Thomson Reuters data.
During its defence against a takeover bid from Pfizer in 2014, AstraZeneca gave a projection of Brilinta sales reaching $3.5 billion by 2023, making it an important part of a $45 billion revenue target announced by the company at the time.
Brilinta's sales in 2015 were $619 million.
Separately, AstraZeneca also announced it had agreed to sell the U.S. rights its old beta-blocker heart drug Toprol-XL to Aralez Pharmaceuticals, marking the latest move by the British company to divest non-core businesses as it focuses on bringing out newer medicines, especially for cancer.
Aralez will pay AstraZeneca $175 million upfront to acquire the rights to Toprol-XL tablets in the United States, and the authorised generic medicine marketed by Par Pharmaceuticals. It will also pay up to $48 million in milestone and sales-related payments, as well as mid-teen percentage royalties on sales. (Additional reporting by Paul Sandle; editing by Kate Holton and Louise Heavens)