Engineered viruses turned back a teenager's untreatable infection

Researchers at the University of Pittsburgh and physicians at Great Ormond Street Hospital in London engineered bacteriophages, viruses that kill specific bacteria, into more effective killers of the patient's drug-resistant infection, after most natural candidates proved too weak on their own.

The team found one natural phage that killed the patient's strain and used genome engineering and selection to make two others effective, then combined all three into an intravenous cocktail. The patient showed objective clinical improvement, including closure of an infected sternal wound, improved liver function, and resolution of infected skin nodules.

This was again a single compassionate-use case, authorized because no other treatment remained, not a trial establishing how often engineered phage therapy succeeds. It demonstrated something the earlier sewage-derived phage cases had not: that phages too weak to use naturally could be engineered into effective therapeutics, widening the pool of usable candidates for future drug-resistant infections.

A weak virus was engineered into one that worked.