Our History

The story of Penicillin began with Alexander Fleming, at St Mary’s Hospital, London in 1928. Fleming discovered that the mould Penicillium notatum produces a substance that kills bacteria.

A decade later, a team at the Dunn School of Pathology, University of Oxford, including Howard Florey, Ernst Chain and Norman Heatley demonstrated the clinical utility of Penicillin and worked on procedures to optimize its production and isolation. For their work on Penicillin, Florey and Chain, together with Fleming, were aware the Nobel Prize in Physiology or Medicine 1945.

The enormous demand for Penicillin generated by World War II was a key reason for the rapid increase in its global production. By the end of 1945, there were 8 British companies - including the chemical manufacturer ICI and the pharmacist Boots, along with the Royal Navy - producing Penicillin in 12 different UK factories. In the US, Pfizer quickly became the world’s largest producer of Penicillin. In the second half of the 1940s, the use of Penicillin surged across Europe. Post-war, the newly founded World Health Organization (WHO) built its own penicillin factories to make the drug globally available.

Antibiotic discovery drives through the 1940s and 1950s were massively successful. Penicillin was quickly augmented by several other classes of effective antibiotics- including cephalosporins which have become the largest class/sub-class of drugs used in clinical medicine. In 1948, Giuseppe Brotzu found that Cephalosporium acremonium produced antimicrobial properties like Penicillium spp. He subsequently worked with the Oxford team of Sir Edward Abraham and Guy Newton who characterised the compound, Cephalosporin C. Oxford Nobel Prize winner Dorothy Hodgkin defined the structure of Cephalosporin C and of Penicillin, using X-ray crystallography.

In his 1945 Nobel Prize lecture, Alexander Fleming spoke of the dangers of antibiotic ‘underdosage’ and warned that common bacteria could evolve to become resistant to the new wonder drugs- a phenomenon which indeed did quickly develop. Within a decade of the discovery and mass production of antibiotics, their low cost and widespread use (including in livestock) led to a number of antibiotic-resistant bacteria strains spreading among humans and animal populations around the globe - a process which is still ongoing.

While pharmaceutical companies developed several additional antibiotics from the 1960s to the 1980s, the recommended use of new drugs for infrequent and short course treatments made them far less lucrative. This lead to pharmaceutical companies changing their focus from discovery and development of new antibiotics to other drugs that are taken regularly and for prolonged periods.

Since the 1990s, pharmaceutical business models have shifted to more profitable drugs. Consequently, breakthrough antibiotics have failed to emerge to tackle the increasingly number of antibiotic-resistant pathogens. A few notable exceptions to this trend have been the discovery and development of Bedaquiline and Cefiderocol.

The IOI was created in January 2021 to help rejuvenate antimicrobial research, investing in the core science underpinning drug discovery to enable the search of solutions to tackle the growing threat of antimicrobial resistance.

Penicillin and the Antibiotic Revolution