Leveraging Bugs as Drugs

Manufacturers must overcome unique challenges to produce effective microbe-based therapies at scale.

Human medicine has made tremendous progress in the past century, increasing our longevity and quality of life. We have been able to cure widespread infectious diseases with antibiotics and vaccines, address behavioral illnesses with antidepressants, and manage cancer care and other diseases with biologics and gene therapies. Yet, chronic illnesses such as diabetes, allergies, and asthma have increased in the past 30 years, contributing to the continuous rise in healthcare costs, which can account for 10–15% of a country’s gross domestic product (GDP) (1). Interestingly, the treatments for these challenging and pervasive health problems may reside in our gut.

Human medicine may be a misnomer, as our bodies are more than just human — human cells account for 43% of the body, while 57% is microbial cells (2). These microbes are not passive passengers. They are organized in a complex and highly metabolically intertwined ecosystem called a microbiome. The gut microbiome alone consists of more than 3,000 microbial species, which amounts to millions of genes that express more than 500,000 metabolites — a third of which can be found in human blood (3). Research in the past decade has shown that these microbes have coevolved with us and are now intertwined with our physiology and health. They are so closely linked to their host that the composition of the gut microbiome is specific to an individual, similar to a fingerprint or DNA. These ecosystems are in a constant state of flux, changing daily based on the host’s food and medicine intake, lifestyle choices, and geographic location. The effects of our gut microbiome on our health go far beyond our digestive system — affecting illnesses such as metabolic diseases (e.g., diabetes), mood disorders (e.g., depression and anxiety), and immune-related conditions (e.g., cancer and rheumatoid arthritis).