Tufts Study Points to Slow Growth for Anti-Infective Vaccines

Although the number of anti-infective vaccines (as distinct fromtherapeutic vaccines for cancers and other noninfectious diseases)entering clinical study each year since 2000 has been higher on averagethan it was in the 1990s, this product area may see little additionalgrowth through the rest of this decade, according to a recent analysisfrom the Tufts Center for the Study of Drug Development (CSDD, Boston,MA, http://csdd.tufts.edu/).

"Despite widespread agreement that new vaccines are an important publichealth priority, development remains slow, expensive, and risky," saysTufts CSDD Director Kenneth I Kaitin.

Since 1990, the number of companies initiating new vaccine studies, andthe number of pathogens they target (38 companies and 35 targets) haveremained essentially unchanged, according to the July–August Tufts CSDD Impact Report.

Each year from 2000 through 2004, clinical studies were initiated for14 products, compared with an average of 12 each year from 1990 to1999.

Kaitin said that although success rates and development times for newvaccines are similar to new biopharmaceuticals, "the benefit-to-riskprofile for vaccines is typically more stringent, liability concernsare often greater, and the return on investment is frequently lower,which partly explains why there aren't more vaccine developmentprograms in place."

He added that in the near term, vaccine research and development islikely to focus on readily transmitted pathogens such as anthrax,dengue, and Ebola.

So far in 2006, the US Food and Drug Administration (Rockville, MD,www.fda.gov) has approved "Rotateq," a rotavirus vaccine, and"Gardasil," a human papilloma virus vaccine. "ACAM2000," a smallpoxvaccine currently undergoing FDA review, may be approved later in theyear, notes the study.

The Tufts CSDD study also found:

• Of eight new vaccines approved in the United States during2000–2005, only three targeted pathogens that were not associated withchildhood diseases or influenza.

• Hepatitis B, hepatitis C, herpes simplex, smallpox, and West Nileviruses have been the five most-studied targets so far in the 2000s andaccount for 60% of all antiviral vaccines currently in development.

• Overall approval success rates for anti-infective vaccinesdeveloped in the 1990s ranged from 17 to 25%.
  

• Clinical development and FDA approval phases for innovativevaccinesapproved in the United States during the past decade averaged 80.0 and13.9 months, respectively.