Hours after AstraZeneca failed in its latest bid to prevent generics of Seroquel from entering the market, Teva Pharmaceuticals Industries has already launched copycat versions of the antipsychotic blockbuster.

The last couple of weeks have seen a number of attempts by the Anglo-Swedish drugmaker to protect its Seroquel (quetiapine) franchise on both sides of the Atlantic but they have failed. On Monday, a lawsuit against the US Food and Drug Administration concerning its stance on copies of the antipsychotic was thrown out of a US court.

Earlier this month, the Anglo-Swedish drugmaker sued the regulator after the latter denied its Citizen Petitions requesting that the agency withhold finally approving any generic with labelling that omits warnings required for branded versions of Seroquel and Seroquel XR. Those warnings relate to hyperglycaemia and suicidal thoughts.

A few days earlier, the UK High Court stated that the patent on the extended-release version of the antipsychotic, ie Seroquel XR, is not valid. AstraZeneca's patent had been challenged by Accord Healthcare, Intas Pharmaceuticals, Novartis' Hexal and Sandoz generics units and Teva and the latter has moved quickly.

Now Teva's UK unit says it has launched its versions of Seroquel and Seroquel XL on "day one of patent expiry". The former is indicated  for schizophrenia and the treatment of moderate to severe manic episodes, while the second drug is approved for schizophrenia and bipolar disorder, and add-on treatment for patients with major depressive disorder who have not responsed to antidepressant monotherapy.

Teva has published its price sheet which shows the considerable difference between branded and generic drugs. For example, a supply of 25-mg coated tablets of Seroquel costs $40.50 compared to £6.08 for the generic. The difference is less pronounced for Seroquel XL, as 50mg of AstraZeneca's drug comes in at £67.66, compared to Teva's price of £50.75.

Kim Innes, commercial director at Teva UK, said that "with the launch of Quetiapine and Quetiapine XL, we’re making more medicines accessible for more people". The firm has now launched ten new products in eleven weeks, including seven on day-one of patent-expiry and "launches like these help towards saving the NHS over £9 billion on generic prescriptions".