Aventis, France's leading pharma company, said on Wednesday, five patients in Japan died after taking its rheumatoid arthritis drug, Arava. The company has now advised doctors to take adequate caution before prescribing the brand containing leflunomide, the active ingredient.

The company's Japanese outfit, Aventis Pharma said the five patients died of interstitial pneumonia, a chronic illness. Eleven other patients, who took the drug since September 12, have either developed or suffered a worsening of the condition. The cases were among 3,412 reported users of the drug in Japan, it said.

Aventis last Friday called upon physicians to refrain from prescribing the medicine to patients who have previously suffered from certain lung conditions, or who have symptoms like coughing after they start taking the drug.

Arava was first launched in the US in 1998 and is currently available in more than 70 countries. Worldwide, 10 people have died due to interstitial pneumonia after taking the drug, a company spokesman added.