For two years and 240 consecutive lots, ritonavir had never failed quality control dissolution tests.

A tiny bit of Form II ritonavir acted as a nucleation site, lowering the activation energy and causing all Form I to crystallize into Form II, with seed crystals spreading through the air.

There are at least five known forms of ritonavir, not just two.

Ritonavir was introduced in 1996 to treat HIV.

By 1998, 75,000 patients across the US were taking ritonavir daily.

Abbott needed to halt all production of ritonavir immediately due to the quality control issues.