Evaluation of Cost Savings to a State Medicaid Program
Objectives: To evaluate the economic impact of implementing a sertraline (Zoloft -- Pfizer) tablet-splitting program on the Nebraska Medicaid program based on the change in total and per-member-per-month (PMPM) prescription drug costs and to identify any real or perceived problems with tablet splitting using switches among selective serotonin reuptake inhibitors (SSRIs) as a proxy indicator.
Design: Retrospective study of prescription claims before and after the tablet-splitting program was implemented.
Setting: Nebraska Medicaid.
Patients: All 14,520 patients who received an SSRI during the study period, including 5,466 patients who received at least one prescription for sertraline.
Interventions: The Nebraska Medicaid program implemented a mandatory tablet-splitting program for sertraline. Pharmacists were paid a supplemental fee to split tablets.
Main Outcome Measures: Total costs, PMPM costs, and switches among SSRIs.
Results: Using regression analysis, sertraline was the only SSRI that showed a downward slope in total cost per month, although the decrease was not statistically significant (P = .1156). Fluoxetine (Prozac -- Eli Lilly) and paroxetine (Paxil -- GlaxoSmithKline) both showed an upward slope, but the increases were not statistically significant (P = .1164 and .0671, respectively). Citalopram (Celexa -- Forest) and fluvoxamine showed significantly positive upward slopes (P = .0001 and .0391, respectively). Sertraline was also the only SSRI that showed a downward slope in PMPM costs (P = .0093). Citalopram, fluvoxamine, fluoxetine, and paroxetine all showed an upward slope in PMPM costs (P = .4494, .0008, .0448, and .0482, respectively). The tablet-splitting program was not associated with a net change in patients being switched to or from sertraline.
Conclusion: Implementing the sertraline tablet-splitting program significantly decreased the PMPM cost of sertraline prescriptions, but it did not significantly decrease total costs of sertraline, nor did it result in disproportionate numbers of patients switching from sertraline to other SSRIs. Total costs and PMPM costs of the other four SSRI drugs did not decrease.

In April 2000 Nebraska Medicaid instituted a cost-minimization program requiring pharmacists to halve 100 mg sertraline (Zoloft -- Pfizer) tablets instead of using the 50 mg tablet for patients taking a 50 mg dose. The 50 mg dose was selected because it is a commonly prescribed dose of sertraline and because splitting the 100 mg tablet has been documented to be an effective means of reducing the cost of sertraline in the hospital setting. No other strengths of sertraline, nor any other drugs, were selected for this pilot program.

Although common in institutional settings and for individual patients who want to reduce their medication expenses, tablet splitting may not be appropriate in all cases. The Nebraska Medicaid sertraline tablet-splitting program was initiated as a pilot program to help the state determine whether mandatory tablet splitting would be an appropriate and effective means of helping control escalating drug costs in Medicaid.

A study reported in 1999 identified sertraline as the most economical selective serotonin reuptake inhibitor (SSRI) for a risk-based Medicare contract using split tablets for 50 mg doses, although no cost estimate was reported. The authors of another retrospective study, this one of 2,779 patients taking SSRIs, estimated that splitting tablets for 50 mg doses decreased the daily cost by $0.70 per patient. Some tablet-splitting programs have required patients, not pharmacists, to split tablets to reduce costs for a managed care organization. One hospital study in which pharmacists split sertraline tablets documented a cost savings of over $260,000 per year, but this amount did not take into account the cost of having the pharmacist split the tablets. At least one state Medicaid program (Washington) had a voluntary tablet-splitting program for sertraline at the time of this study, but cost savings estimates had not been reported.

In recognition of problems reported with tablet splitting, the Nebraska Drug Utilization Review (DUR) Board recommended that pharmacists dispense presplit tablets and counsel patients regarding the half-tablet dosage form. The DUR board anticipated that presplitting would ensure that the tablets were split evenly, which is often not the case when patients split tablets themselves, and that any special considerations for the split tablet would be clearly stated on the label and incorporated into patient counseling at the time the prescription was dispensed. Prescribers and pharmacists were permitted to request prior authorization to dispense 50 mg sertraline tablets to individual patients for whom split tablets were deemed therapeutically inappropriate. (Prior authorization was not required for 25 mg or 100 mg tablets or for any other SSRI.)

Pharmacies in Nebraska were paid a supplemental professional fee of $0.15 per tablet split. The state set this fee after looking at a state-employed dispensing pharmacist's base salary, which was $18.00/hour at the time of the study, and estimating that the pharmacist could split two tablets per minute. The claims data reviewed for this study do not include information on whether a pharmacist, pharmacist intern, or pharmacy technician split tablets for a given prescription or the usual and customary amount a pharmacy charged for splitting tablets for non-Medicaid patients.