Bivalirudin

How it works

Leech-inspired, lab-built: it blocks thrombin, the clotting enzyme, during heart stenting, then wears off fast. Commitment issues.

What it's made of

20 amino acids, by design. One end plugs the active site of thrombin; the other copies the tail of hirudin, from the leech. In the middle, a bridge of four glycines.

What it's for

Prescribed for

An anticoagulant during coronary angioplasty, also in people with heparin-induced thrombocytopenia.