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

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

Abbott stated that the semi-solid formulation of ritonavir began to change into a crystal form, a transformation they believed was a scientific and chemical impossibility.

Ritonavir production at an alternative factory in Italy initially passed dissolution tests.

Technicians found that the clear ritonavir capsules were turning white and cloudy, filled with millions of tiny needle-like crystals.

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