Like its partner Bristol-Myers Squibb, Sanofi-Aventis felt the effects of generic competition to its Plavix in the third quarter of 2006, posting a 1.1% decline in sales to 6.9 billion euros ($8.8bn) and earnings per share down more than 12% to 1.26 euros.

Plavix (clopidogrel) sales still managed a 2.5% increase in the quarter to 543 million euros, despite the impact of generic competition to the drug in the USA from Canadian drugmaker Apotex. Although the generic was only on the market for a matter of days before an injunction suspended its sales, Apotex was able to flood the US market with supply sufficient for the whole of 2006, and part of 2007.

Last week, B-MS, which has direct marketing rights to Plavix in the USA, reported a 43% drop in the product’s revenues as a result of generic competition.

And aside from the Plavix effect, Sanofi is also being impacted by generic competition to four other critical products, as well as government price cuts in some of the company’s key markets like France and Germany.

For example, Allegra (fexofenadine) for allergies fell 55% to 156 million euros, while Amaryl (glimepiride) for diabetes was down 44% to 106 million euros, while two other big sellers – Eloxatin (oxaliplatin) and Taxotere (docetaxel) were pegged back by increased competition in the oncology sector. Eloxatin sales managed to gain just 1.7% to 417 million euros, and Taxotere climbed 5% to 429 million euros, well shy of their growth rates in earlier quarters.

The vaccines business also suffered a downturn, contributing 647 million euros, down 7%, due to delays in shipping influenza vaccines to the USA.

On the positive side, sales of antithrombotic Lovenox (enoxaparin) rose 9% in the quarter to 583 million euros and the Stilnox/Ambien sleeping pill franchise advanced 34% to 543 million euros. However, patents on Lovenox are being challenged by Teva and Amphastar Pharmaceuticals, with a court date set for December 4, and it is also facing near-term competition from GlaxoSmithKline’s Arixtra (fondaparinux sodium), which was recently filed for acute coronary syndromes.

Meanwhile, one of the great hopes in Sanofi’s pipeline, obesity drug Acomplia (rimonabant), made its first contribution to the firm’s coffers after being launched in Europe in June. It made 11 million euros in the quarter, although some countries including Germany have refused to reimburse the product, making its future uncertain, according to analyst Navid Malik of Collins Stewart. Its approval in the USA has also been delayed by requests for more information from the US Food and Drug Administration.

Malik also points to other recent disappointments in Sanofi’s pipeline, including the FDA’s recent rejection of dronedarone for atrial fibrillation, as well as data on its H5N1 flu vaccine that, he believes, indicate that rival GSK has the lead in this field.