Modern medicine - unfinished

Magic bullets

Paul Ehrlich: Salvarsan 606

• Robert Koch’s research team continued his research identifying bacteria and looking for ways to kill these bacteria

• One member of his team, Paul Ehrlich, reasoned that, if certain dyes could

  stain bacteria, perhaps certain chemicals could kill them

• He set up a private laboratory and a team of scientists

• By 1914 the team had discovered several magic bullets - compounds that would kill the bacteria without harming the human host

• The most successful compound was based on arsenic and it

treated syphilis which is a sexually-transmitted infection which can ultimately be fatal. The

name of this compound was Salvarsan 606 and it was discovered in 1909 (see below for the

story). By 1910, Salvarsan 606 was being given to patients, although it was not an easy drug to

dispense as it had to be dissolved and then injected. Nonetheless, it was an important step

forward because it demonstrated that chemical treatments could work and inspired doctors to

continue their research.

Geek Facts: Salvarsan 606 derives its name from the testing process. Ehrlich tested over 605

chemical compounds based on arsenic and concluded that none of them worked. However, not

wanting to give up, in 1909 Ehrlich’s assistant Sahashiro Hata re-tested all 606 compounds and

found that number 606 worked. The 606th compound was therefore called Salvarsan 606. They

tested on rabbits.

Gerhardt Domagk: Prontosil

One researcher who was looking for chemical treatments was Gerhardt Domagk. He was

investigating chemicals which could cure blood poisoning. In 1932, he discovered a compound,

Prontosil, which seemed to be effective in the laboratory but he was nervous about testing this

compound on a human. Luckily (!), a perfect testing opportunity presented itself when his own

daughter pricked her finger on an infected needle and subsequently developed severe blood

poisoning. Fearing that she would die otherwise, he gave her the untested Prontosil compound.

It worked and she survived. The second magic bullet had been found.

The sulphonamide ‘family’ of drugs

Researchers now needed to find out exactly why Prontosil worked which meant that they needed

to identify the active ingredients. After two years, French researchers identified that the

active ingredient in Prontosil was a sulphonamide derived from coal tar.

Drug companies now raced to find cures based on sulphonamides. Drugs were developed to cure

and control scarlet fever, meningitis, gonorrhoea and pneumonia. These drugs based on

sulphonamides saved many lives. Moreover, the success of Prontosil also encouraged other

researchers to look for more chemical treatments for other diseases.

Penicillin

Creation of the NHS

Genetic causes of disease and the discovery of DNA

Advances in prevention since 1900

New technologies (advances in diagnosis and treatment)

Case study: Lung cancer