Teva Pharmaceutical Industries has been given the go-ahead in the USA for its generic versions of Merck & Co's blockbuster antihypertensives Cozaar and Hyzaar.

The US Food and Drug Administration has granted final approval for the Israeli drugmaker’s copycat versions of Cozaar (losartan) and Hyzaar (losartan plus hydrochlorothiazide) and as the first company to file Abbreviated New Drug Applications, it has been awarded 180-day exclusivity for these products across the pond. Teva will begin shipping the drugs immediately.

Earlier this week, a US court rejected an attempt by Apotex and Roxane Laboratories to challenge Teva's right to exclusivity. Last week, the two generic drugmakers sued the FDA,claiming that a key patent for the drugs had expired, so no company was eligible for the exclusive rights.

Although expected, the arrival of generic Cozaar and Hyzaar will hurt Merck quite considerably, given that the drugs have annual combined sales in the USA of about $1.6 billion.

Meantime, Teva is presenting several new studies about its central nervous system portfolio at the American Academy of Neurology annual meeting in Toronto. They will include new data on the company’s investigational oral multiple sclerosis treatment laquinimod, as well as its established MS blockbuster Copaxone (glatiramer acetate).