Question: In 1923, what was discovered to be safer to treat Diphtheria Toxin?
Sentence: In 1923 parallel efforts by Gaston Ramon at the Pasteur Institute and Alexander Glenny at the Wellcome Research Laboratories (later part of GlaxoSmithKline) led to the discovery that a safer vaccine could be produced by treating diphtheria toxin with formaldehyde.
Answer in sentence: yes