June 11, 2007

Sanofi-Pasteur: Approval Delays Add to Pentacel Problems

Although on the market in various countries, the US launch of Pentacel is proving to be a problematic process for Sanofi-Pasteur. The drug is already likely to be hindered by failing to match US vaccination recommendations, unlike competing products such as GSK's Pediarix. The FDA's decision to delay approval, citing technical reasons, will further limit Pentacel's overall commercial potential.

Pentacel, Sanofi-Pasteur's combination vaccine against diphtheria, tetanus, pertussis (DTP), polio and as well as Haemophilus influenzae type B (Hib) is currently marketed in nine countries including the UK and Canada, where Pentacel was first registered in 1997. By April 2006, over 13.5 million doses had been distributed in a four-dose injection schedule vaccinating children at two, four, six and 18 months of age.

However, gaining approval for Pentacel in the US has proved difficult for Sanofi, the market leader in the DTP vaccines sector with sales totaling $1.1 billion in 2006. The first submission for Pentacel was made in 2005, followed by an FDA recommendation for pediatric approval in January 2007. The recent FDA announcement to delay a decision on the vaccine until November comes as a result of Sanofi's decision to shift the control assays for Pentacel's pertussis component from the company's Canadian to its US facilities.

The delay in approval is not the only issue associated with the US launch of Pentacel. Although Sanofi's vaccine would be the first DTP-based combination product for infants in the US that includes both polio and Hib components, its commercial potential will be limited by the national immunization schedules: US authorities do not recommend a concomitant vaccination of children under the age of 12 months against DTP and Hib.

Therefore, the use of Pentacel would currently be limited to the fourth DTP booster shot administered at 18 months of age, significantly restricting its market opportunity. GSK, Sanofi's strongest competitor in the DTP sector, has avoided this issue by omitting the Hib component from its own DTP combination Pediarix (DTP/polio/HepB), which has become firmly established in the US market following its launch in 2003.

Thanks to the FDA's decision, GSK will continue to enjoy a leading position at least until the end of the year. Even when approved, Pentacel will only be a significant competitor if Sanofi-Pasteur manages to change the CDC's current guidelines in their favor.