Walking the toll road

Even after a series of clinical setbacks in the mid-2000s cooled investor and pharma interest in the once white-hot field of toll-like receptors, several companies continued toiling away. Now the spark may be rekindling as new TLR biology has been elucidated, and new methods have been developed to improve safety and efficacy by delivering TLR modulators to the right cells at the right time.

Because of their role in the immune response against bacteria and viruses, TLRs were flagged early on as targets for infectious disease. But they were also considered targets for diseases where the immune response is under- or overactivated, such as cancer, allergy and inflammatory conditions...