Reference
Where the seven locks were found
None of these molecules appeared on a Vienna bench first. These are the labs that found them and the regulators that still limit the claim.
Pfizer, Sandwich (discovery campus)
Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
Sildenafil was drawn up here as UK-92,480, a candidate for angina. The heart numbers were flat; a side effect the volunteers kept reporting was not, and the blueprint was redrawn. Viagra — and the whole PDE5 line that followed — dates back to this Kent site.
ICOS Corporation with Eli Lilly
22021 20th Avenue SE, Bothell, WA 98021, USA
Tadalafil was identified at this Washington biotech and taken through late trials with Eli Lilly. Its signature was drafted in the pharmacokinetics, not the chemistry: it left the body far more slowly than its rivals, which is the single line that turned it into the long-window tablet the class now measures itself against.
Bayer, Wuppertal
Aprather Weg 18a, 42113 Wuppertal, Germany
The Wuppertal laboratories drew vardenafil, later sold as Levitra and the orodispersible Staxyn. Milligram for milligram it grips PDE5 more tightly than either sibling, which is why its labelled doses read so much smaller than sildenafil's on the same page.
Bayer, Leverkusen
Kaiser-Wilhelm-Allee 1, 51373 Leverkusen, Germany
Ciprofloxacin came off Bayer's fluoroquinolone drawing board in the early 1980s — a fluorine atom and a piperazine ring bolted onto the older nalidixic-acid frame, giving a broad-spectrum antibiotic that reaches tissues most oral drugs cannot. The same chemistry explains both its reach and the tendon and nerve cautions now set in bold on its label.
Parke-Davis / Warner-Lambert (historic)
2800 Plymouth Road, Ann Arbor, MI 48105, USA
Gabapentin was drafted at Parke-Davis as a GABA analogue meant to quiet over-firing neurons. It never touched the GABA receptor as planned; it damped calcium channels instead and found a durable second use in nerve pain and epilepsy. Warner-Lambert, and later Pfizer, carried Neurontin to market from this Michigan base.
Janssen Pharmaceutica
Turnhoutseweg 30, 2340 Beerse, Belgium
Mebendazole came out of the benzimidazole programme Paul Janssen's laboratories ran in the 1960s and 70s. The blueprint was elegant and narrow: starve the parasite by blocking its uptake of glucose, and leave the host largely untouched because the drug is so poorly absorbed from the gut. Vermox traces to this Belgian campus.
Merck & Co. with the Kitasato Institute
Kitasato University, Minato City, Tokyo, Japan
Ivermectin began as an avermectin drawn from a single soil Streptomyces isolate found by Satoshi Ōmura's team in Japan and developed with Merck's William Campbell — work that shared the 2015 Nobel Prize in Medicine. It reshaped veterinary and then human parasitology, above all in river blindness.
WHO / Mectizan Donation Program
Avenue Appia 20, 1211 Genève, Switzerland
The World Health Organization frames the mass-treatment programmes that made ivermectin famous — onchocerciasis and lymphatic filariasis — and its guidance sits beside the FDA label in our reading of the antiparasitics. The Mectizan donation, running since 1987, is the backdrop to most of what ivermectin is actually approved to do.
U.S. Food and Drug Administration
10903 New Hampshire Avenue, Silver Spring, MD 20993, USA
The American regulator whose approved prescribing information fixes the doses, boxed warnings and interaction rules we quote. Where a page here and the current FDA label diverge, the label is the authority — the nitrate contraindication for the PDE5 drugs and the fluoroquinolone boxed warning above all.
European Medicines Agency
Domenico Scarlattilaan 6, 1083 HS Amsterdam, Netherlands
The EU regulator whose scientific assessments and product information sit alongside the FDA label in our reading. Its reviews are particularly useful on the fluoroquinolone safety restrictions and on the reasoning behind each approved European indication.
Why the history matters
Provenance is not trivia. Sildenafil's start as a failed angina candidate explains both its cardiovascular cautions and its accidental fame; tadalafil's slow clearance out of the ICOS labs is the reason a long-window tablet exists; vardenafil's potency out of Wuppertal is why its labelled doses look so small. Ciprofloxacin came from bolting a fluorine atom and a piperazine ring onto an older scaffold, and that reach is exactly why its safety label runs so long. Gabapentin was built to mimic a neurotransmitter, missed that target entirely, and found a second life damping calcium channels. Mebendazole was drawn narrow on purpose — barely absorbed, so it starves the worm and spares the host. Ivermectin came from a single soil microbe and went on to a Nobel Prize and a river-blindness programme that treats hundreds of millions. Read together, the origins explain why seven very different medicines still behave the way they do. Each blueprint links back to the institution that shaped the molecule.