Vaccine R&D: past performance is no guide to the future.

Vaccines offer the most cost-effective solution to prevent both communicable and non-communicable disease in poor countries. Published studies suggest that vaccine research is seeing declining success. This study updates the latest analyses on success rates in vaccine research, and examines the potential causes of decline and their ongoing impact. Success rates are shown to decline, the observed probability of market entry being just 1.8%, almost a fourfold decline over 5 years, but in the context of a very different product portfolio from that seen in earlier studies. DNA vaccines see high Phase I failures as expected, and therapeutic vaccines have lower success rates than prophylactic vaccines. The changing scientific challenge, lack of investment and lack of co-operation are highlighted as potential causes of the decline. Many issues have now been resolved, but co-operation between academia, regulators and industry remains a significant challenge, requiring links across new disciplines and technologies.