The effect of a copay increase on pharmaceutical utilization, expenditures, and treatment continuation

Objective: No research has evaluated the impact of an increase to a copay t hat is reflective of today's healthcare market. This study examined the eff ect of an increase from a $10 to $15 copay for brand drugs on key pharmaceu tical utilization measures, including participation rates, treatment contin uation, and expenditures, in an adult population. Study Design: A quasi-experimental, pre-post design with control group was used. Patients and Methods: Two different employer plans implemented an increase from $10 to $15 for brand copays in January of 1997. The utilization and ex penditures of these plans were compared with those of a control group with a constant brand copay of $10 for 6 months preceding and 6 months following the copay increase. Results: When other predictor variables were controlled for, the copay incr ease was not associated with: a statistically significant difference in ove rall utilization compared with the control group, although brand utilizatio n was significantly lower in: the copay group. Savings to the payer were su bstantial, and resulted primarily from cost-shifting, reduction in:brand ut ilization, and an increase in the generic fill rate. The rates of continuat ion with chronic medications in the 6 months following the copay increase w ere not reduced in the copay group compared with the control group. Conclusion: A copay Increase can provide substantial savings to a payer wit hout being a major deterrent to overall utilization or resulting in discont inuation of chronic medications.