Health Care Policy, Harvard Medical School in Boston, Massachusetts, USA. huskamp@hcp.med.harvard.edu
The Hatch-Waxman Act of 1984 provides pharmaceutical manufacturers with an incentive to introduce reformulations of existing products that are about to lose patent protection, to extend marketing exclusivity and maintain high prices. Antidepressant reformulations are particularly common. To determine whether the use of reformulations confers benefits, we examined who uses them and whether they affect the duration of medication use. We found some evidence of benefit for subgroups of antidepressant users, although benefits varied across reformulations.