AstraZeneca has confirmed that it has agreed to settle 17,500 liability cases in the USA relating to its antipsychotic blockbuster Seroquel for approximately $198 million.

The Anglo-Swedish drugmaker said that specific terms of the agreements, “which are the result of court-ordered mediation, are confidential” and it is still participating in the process “covering claims in both federal and state jurisdictions”. Some 2,900 additional cases have been dismissed and the only jury trial to date (in March) resulted in a victory for AstraZeneca.

The company has been facing thousands of lawsuits based on claims that warnings on Seroquel (quetiapine) did not adequately to alert users to the potential increased risk of diabetes. In April it agreed to pay $520 million to the US government to settle alleged claims about improper marketing of the drug and agreed to a five-year “corporate integrity agreement”.

AstraZeneca noted that as of June 30, “no provision had been made in respect of any settlements” but added that the payments will not affect its full-year earnings per share guidance of $6.35-$6.65. Seroquel is a major earner for the firm and had second-quarter sales of $1.35 billion, up 8%.

Industry observers believe that paying out $198 million to cover so many cases works out pretty cheaply for AstraZeneca, and also suggests that it is difficult to prove liability.