Bextra withdrawal dents Pfizer’s sales juggernaut
pharmafile | April 22, 2005 | News story | Sales and Marketing |Â Â Â
The suspension and withdrawal of Pfizer's Cox-II inhibitor Bextra has forced the company to cut its profit forecast for 2005, adding to pressure from patent expiries.
The company has warned investors that its earnings are likely to fall 7% pushing them down from $2.12 per share to $1.98.
Pfizer is unused to breaking bad news to investors, but falling sales of Neurontin, Accupril and Diflucan because of patent expiries, along with the blow to its Cox-II franchise has undermined otherwise strong growth.
Even before the FDA's request for the withdrawal of Bextra (valdecoxib) in April, sales of the drug had been falling in the first quarter of 2005, posting a huge 79% fall over the three-month period.
Meanwhile, despite being judged to have the best safety profile of the remaining Cox-IIs by an FDA panel, global sales of Celebrex fell sharply as well, down 47%, as prescribers deserted the class en masse.
The FDA requested Bextra's wthdrawal from the market in early April, telling the company a new appraisal of its benefit/risk profile required its suspension.
Pfizer then voluntarily withdrew the drug across Europe, and Canada, Hong Kong, Singapore, Malaysia, South Africa, the Phillipines and Mexico. The company says it "respectfully disagrees" with the FDA's position, and says it will maintain dialogue to see if the drug can be returned to the market.
The FDA said risk of the rare but serious skin reaction – Stevens-Johnson syndrome – in addition to its cardiovascular side-effects made it too risky a drug to remain on the market.
Stevens-Johnson syndrome is a potentially fatal blistering skin reaction including toxic epidermal necrolysis (serious skin and mouth blistering and peeling) and is seen in a small number of patients taking all non-steroidal anti-inflammatory drugs (NSAIDs) but Bextra seems to cause more cases.
UK regulator the MHRA estimates under 10,000 patients in the UK are currently taking Bextra, of whom less than 3,000 recently started treatment.
The UK Committee on Safety of Medicines has been informed of two patients with the serious blistering skin reactions from taking valdecoxib, contributing to worldwide reports of 155 cases.
The news is the latest response from the regulators following the withdrawal of Vioxx in September 2004 because of a link to increased risk of heart attack and strokes. A special FDA panel concluded earlier this year that all Cox-IIs carried some increased risk of cardiovascular side-effects, and recommended labelling changes, which the US regulator has now confirmed.
New boxed warnings of increased cardiovascular and gastrointestinal side-effects will be carried by all NSAIDS and not just the Cox-II class in the US, but the new labelling will further undermine confidence in the newer drugs.
In the US, Pfizer has agreed to a complete suspension of the availability of Bextra, instructing patients to stop taking the drug and contact their doctors. In Europe, patients already taking the drug will be allowed to remain on it under supervision, but no new patients should be prescribed it.
Merck Sharpe & Dohme's Arcoxia was singled out by the EMEA as carrying the greatest risk of all of the remaining drugs in an earlier assessment this year. Its contraindication in patients with heart problems and even uncontrolled blood pressure is expected to be confirmed soon.
