The Filipino chemist who found erythromycin never saw a royalty
In 1952 Abelardo Aguilar mailed soil samples from the Philippines to Eli Lilly and pulled a new antibiotic from a microbe living in them. Lilly launched it that year as Ilosone, named after Iloilo province where he had dug. Aguilar asked for a leave, then royalties, and got neither before he died in 1993.
The drug comes from the bacterium now called Saccharopolyspora erythraea. Lilly won its patent in 1953. Aguilar had allegedly been promised a visit to the company's Indianapolis plant that never materialised, and a 1956 letter to Lilly's president asking only for time away was turned down. In 1993 he requested royalties to fund a foundation for poor and sick Filipinos; that too was refused, and he died that September. Today the medicine sits on the World Health Organization's essential list, and in 2023 it was the 235th most prescribed drug in the United States.
Erythromycin belongs to the macrolide family. It binds the larger subunit of the bacterial ribosome and jams the step where a growing protein chain shifts along, so bacteria cannot build working proteins and stop growing. It treats respiratory and skin infections, chlamydia and syphilis, is generally safe for people allergic to penicillin, and an eye ointment is routinely advised for newborns. Stomach acid destroys it easily, so oral forms are coated or made as more stable salts; the Japanese firm Taisho invented clarithromycin in the 1970s partly to fix that weakness. Chemists found it so hard to make from scratch, with 10 stereogenic carbons, that Robert Woodward's synthesis was published only in 1981.
A side effect became a use. The molecule also stimulates motilin receptors in the gut, which is why cramps and diarrhoea are common, but doctors exploit it to speed stomach emptying in gastroparesis and to clear the stomach before endoscopy. It also blocks the liver enzyme CYP3A4, so it can dangerously raise levels of other drugs such as simvastatin, and combining it with certain heart medicines has been linked to sudden cardiac death.
An old generic is not always cheap. The US price of a 500 mg tablet rose from 24 cents in 2010 to $8.96 in 2015, and Medicaid paid about $2.7 million more for it in 2016 than the year before. Resistance matters too, particularly for group B strep, which pregnancy screening programmes track.
Source: Erythromycin
