The European Medicines Agency (EMA) has requested a label update to provide clearer guidance on the safe use of the anticoagulant Pradaxa (dabigatran).

The review has confirmed the drug’s positive benefit-risk balance as a stroke prevention treatment for certain patients, but stated the need for clearer notes on the medicine’s risks and what to do in case of bleeding.

The Boehringer Ingelheim drug is recommended for patients with non-valvular atrial fibrillation or following hip or knee replacement.

Because all blood-thinning drugs can cause bleeding, the EMA has maintained close post-market surveillance of this product.

The EMA’s scientific advisory committee, the CHMP, found that the incidence of fatal bleedings with Pradaxa in post-marketing data was significantly lower than in the clinical trials that led to the drug’s authorisation in 2008.

In November 2011, a safety review concluded that the drug should be used with caution, and at lower doses, with patients who were elderly or had moderate renal impairment.

Pradaxa “remains an important alternative to other blood-thinning agents,” the EMA said.

However, the guidance for doctors and patients should be strengthened to include details of the risks, when the drug must not be used, and how to manage patients if bleeding occurs.

In particular, patients taking Pradaxa should seek urgent medical attention of they fall or suffer any injury.

The European Commission is expected to confirm this opinion.

Bristol-Myers Squibb’s anti-platelet therapy Plavix (clopidogrel) has become the latest blockbuster to lose patent protection in the US.

A mainstay of heart disease treatment since 1997, Plavix faces immediate generic competition from Cardinal Health.

BMS, who markets Plavix in partnership with Sanofi, has said it will cease promoting the drug immediately following patent expiry.

Used together with aspirin, Plavix is the standard blood-thinning therapy for people who have suffered a heart attack.

The product earned BMS $7.1bn in 2011, a third of the company’s revenue.

BMS has decided not to follow the example of Pfizer, who promoted Lipitor extensively for six months after its US patent expiry, because the usual six-month exclusivity to one generic supplier will not apply.

The reason is that the first authorised supplier of generic clopidogrel, Apotex, forfeited its exclusivity period due to unlicensed sales in 2006.

As a result, seven companies have already received tentative approval to sell generic clopidogrel in the US. Cardinal Health plans a next-day launch. A spokesman for Sun Pharmaceutical Industries said the company would lose no time: “I would not be surprised if there was a stopwatch involved.”

BMS’s 2011 annual report predicted “a rapid, precipitous and material decline in Plavix net sales” following expiry of its US patent.

The company has developed a new blood-thinning drug, Eliquis, in partnership with Pfizer. Its FDA approval for stroke prevention is expected in June.