Initial results of the use of prescription order change forms to achieve dose form optimization (consolidation and tablet splitting) of SSRI antidepressants in a state Medicaid program.
BACKGROUND
One method to reduce drug costs is to promote dose form optimization strategies that take advantage of the flat pricing of some drugs, i.e., the same or nearly the same price for a 100 mg tablet and a 50 mg tablet of the same drug. Dose form optimization includes tablet splitting; taking half of a higher-strength tablet; and dose form consolidation, using 1 higher-strength tablet instead of 2 lower-strength tablets. Dose form optimization can reduce the direct cost of therapy by up to 50% while continuing the same daily dose of the same drug molecule.


OBJECTIVE
To determine if voluntary prescription change forms for antidepressant drugs could induce dosing changes and reduce the cost of antidepressant therapy in a Medicaid population.


METHODS
Specific regimens of 4 selective serotonin reuptake inhibitors (SSRIs)- citalopram, escitalopram, paroxetine, and sertraline- were identified for conversion to half tablets or dose optimization. Change forms, which served as valid prescriptions, were faxed to Oregon prescribers in October 2004. The results from both the returned forms and subsequent drug claims data were evaluated using a segmented linear regression. Citalopram claims were excluded from the cost analysis because the drug became available in generic form in October 2004.


RESULTS
A total of 1,582 change forms were sent to 556 unique prescribers; 9.2% of the change forms were for dose consolidation and 90.8% were for tablet splitting. Of the 1,118 change forms (70.7%) that were returned, 956 (60.4% of those sent and 85.5% of those returned) authorized a prescription change to a lower-cost dose regimen. The average drug cost per day declined by 14.2%, from Dollars 2.26 to Dollars 1.94 in the intervention group, versus a 1.6% increase, from Dollars 2.52 to Dollars 2.56, in the group without dose consolidation or tablet splitting of the 3 SSRIs (sertraline, escitalopram, and immediate-release paroxetine). Total drug cost for the 3 SSRIs declined by 35.6%, from Dollars 333,567 to Dollars 214,794, as a result of a 24.8% decline in the total days of SSRI drug therapy and the 14.2% decline in average SSRI drug cost per day. The estimated monthly cost avoidance from this intervention, based on pharmacy claims data, was approximately Dollars 35,285, about 2% of the entire spending on SSRI drugs each month, or about Dollars 0.09 per member per month. Program administration costs, excluding costs incurred by prescribers and pharmacy providers, were about 2% of SSRI drug cost savings.


CONCLUSIONS
Voluntary prescription change forms appear to be an effective and well-accepted tool for obtaining dose form optimization through dose form consolidation and tablet splitting, resulting in reduction in the direct costs of SSRI antidepressant drug therapy with minimal additional program administration costs.
Hamer
Ann M
AM
Drug Use Research & Mangement Program, Oregon State University College of Pharmacy, Portland, OR 97201-4952, USA. hamera@ohsu.edu
Hartung
Daniel M
DM
Haxby
Dean G
DG
Ketchum
Kathy L
KL
Pollack
David A
DA
D018687:Antidepressive Agents, Second-Generation / Q000008:administration & dosage* / Q000191:economics*; D015283:Citalopram / Q000008:administration & dosage / Q000191:economics; D017046:Cost Savings; D016527:Drug Costs; D011307:Drug Prescriptions; D004363:Drug Utilization; D006801:Humans; D007356:Insurance, Pharmaceutical Services; D016014:Linear Models; D008484:Medicaid; D018803:Models, Economic; D009922:Oregon; D017374:Paroxetine / Q000008:administration & dosage / Q000191:economics; D010818:Practice Patterns, Physicians'; D015397:Program Evaluation; D012107:Research Design; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage* / Q000191:economics*; D020280:Sertraline / Q000008:administration & dosage / Q000191:economics; D013607:Tablets
D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram; D017374:Paroxetine; D017367:Selective Serotonin Reuptake Inhibitors; D020280:Sertraline; D013607:Tablets