A UK High Court has ruled against AstraZeneca‘s bid to protect its patent on a new formulation of its antipsychotic drug Seroquel.

The pharmaceutical company hoped that it could preserve its rights on the drug until May 2017 by creating a prolonged-release version of the medicine, named Seroquel XR.

The UK patent will expire this month as planned.

The UK is the first country to render the drug invalid. Earlier this month a district court in the Netherlands approved the extension of the patent.

Similar trials have been concluded in the US and Spain, and decisions are pending.

AstraZeneca said in a statement, "AstraZeneca is disappointed with the court’s decision. However, the company remains committed to defending its intellectual property protecting Seroquel XR."

The firm has filed a lawsuit against the US Food and Drug Administration for refusing to delay the market entry of generic versions Seroquel.

The company is seeking to overturn the agency’s rejection of AstraZeneca’s Citizen Petitions, which requested that generic copies of the drug come with warnings about high blood sugar and suicidal tendencies.