The development of new antibiotics

The development of new drugs requires a large investment in time, effort, scientific research and money. Developing new antibiotics to combat the rise in antibiotic-resistant bacteria in particular is a challenge as currently only a small number of patients contract these infections and meet the requirements for traditional clinical trial participation. However, with antibiotic resistance reaching dangerously high levels across the global it is critical that we work towards new ways to prevent and treat bacterial infections.

The progression of new drugs to market
There has been a lot of study into the clinical development success rates for new drugs in development. With a number of stages and approval processes to pass, a vast number of potential drug candidates never come close to making it to market.

Phase 1

• Safety testing, not dependent on efficacy of results to advance
• Approximately 63.2% of drug candidates progress past Phase 1 clinical trials

Phase 2

• The first stage where proof-of-concept is deliberately tested in human subjects
• A decision must be made by the industry whether to pursue the drug candidate through Phase 3 clinical trials which are large and expensive
• Approximately 30.7% of drug candidates progress past Phase 2 clinical trials

Phase 3

• Generally the longest and most expensive trials to conduct
• Approximately 58.1% of drug candidates progress past Phase 3 clinical trials

FDA Approval

• Drug candidates that pass through all three clinical trial phases are then submitted to the FDA (in the US) for approval either for a New Drug Application (NDA) or a Biologic License Application (BLA).
• The likelihood of drug candidates being approved by the FDA at this stage is 85.3%.

Overall, the probability of a new drug candidate progressing from Phase 1 clinical trials to approval by the FDA and progression to market is only 9.6%.

Current development of new antibiotics
According to The Pew Charitable Trusts (PEW), there are currently 41 new antibiotics in clinical development for the US market. In response to the growing global concern regarding increasing antibiotic resistance, PEW has been tracking the pipeline of clinical development for new antibiotics. PEW regularly updates the data which identifies the drug, manufacturer, potential targets and the stage in development process.

Key findings

• The current analysis shows that of the 41 new antibiotics in development, 15 are in phase 1 clinical trials, 13 are in phase 2 clinical trials and 11 are in phase 3 clinical trials. Two drugs have completed phase 3 clinical trials and their New Drug Applications are currently being reviewed by the FDA.
• At least 16 of the new drugs in development have the potential to address pathogenic infections considered an urgent threat to public health by the CDC.
• Fewer than 1 in 3 drugs currently being developed represent a novel drug class or mechanism of action.
• Over 80% of the products being developed are done by small companies rather than the large pharmaceutical firms.

As demonstrated, the overall probability of a new drug in development progressing to market is estimated to be less than 10%. Therefore, it is inevitable that many of these new antibiotics will not be approved. Considering the urgent need for new antibiotics, there are not enough drugs in development and more needs to be done to address the threat of antibiotic resistance.

PEW is also analysing the development of non-traditional products to prevent or treat bacterial infections.