Sanofi Recalls 800,000 Swine Flu Shots on Potency (Update2)

Dec. 15 (Bloomberg) -- Sanofi-Aventis SA recalled 800,000 doses of swine flu vaccine after testing showed the potency of the batches was too low, the U.S. Centers for Disease Control and Prevention said today.

The shots are safe, and people who have already been inoculated don’t need to get vaccinated again, said Anne Schuchat, head of the CDC’s National Center for Immunization and Respiratory Diseases. Doctors who have unused shots from the batches should return them, she said today in a phone interview.

The recalled shots are preservative-free syringes of a low- dose version made for children ages 6 months through 35 months. There are no remaining preservative-free shots available for children younger than 2 years old. While the preservative, called thimerosal, has been shown in studies to be safe, some parents are wary of it, Schuchat said.

“This is not safety related,” Schuchat said. “Primarily we wanted to let the doctors know that there’s a heads-up, that this particular product is being voluntarily recalled with no clinical or safety concerns.”

Multidose vials are still available for children of all ages, and London-based AstraZeneca Plc’s inhaled version without preservative is available for children 2 years and older.

September Start

Sanofi began delivering swine flu vaccine in the U.S. in September, with the bulk of deliveries expected in the fourth quarter. The U.S. has ordered 75 million doses from the Paris- based company.

After flu vaccine is shipped, manufacturers maintain samples from each batch and continue to test the safety and potency. The testing is meant to catch decreases in potency over time, possibly because the key ingredient, antigen, clings to the walls of the syringe.

The shots passed tests when they first shipped, and their potency dropped in subsequent tests by 10 to 12 percent, Schuchat said. The batches were shipped in mid-November, and most shots have already been administered.

“These lots passed all quality controls and met all specifications required by the government agencies at the time of shipping,” Sanofi said in a statement today.

Sanofi’s vaccine sales totaled 1.05 billion euros ($1.5 billion) in the third quarter, including 78 million euros from H1N1 influenza shots. In October, the company forecast that sales of H1N1 vaccine would surge to about $500 million in the fourth quarter. The company plans a seminar Dec. 17 to brief investors and analysts on the vaccine business.

Swine flu infected 50 million people in the U.S. and killed an estimated 10,000 through Nov. 14 from the start of the pandemic in April, the CDC said on Dec. 10. Swine flu, also known as H1N1, was first identified in April and swept the globe at an unprecedented rate before cases declined in the U.S. in the past few weeks. In a typical season, 36,000 people die of the flu.

To contact the reporters on this story: Tom Randall in New York at trandall6@bloomberg.net

To contact the editor responsible for this story: Reg Gale in New York at rgale5@bloomberg.net