Drug persistency patterns for patients treated with rivastigmine or donepezil in usual care settings.

OBJECTIVE: To compare levels of persistency with 2 cholinesterase (ChE) inhibitors--rivastigmine and donepezil--for the treatment of Alzheimer's disease (AD) through the use of administrative claims data. METHODS: This retrospective cohort study identified treatment-naive, community-based AD patients having an initial prescription (index event) for rivastigmine or donepezil between June and December 2000, in the United States, from pharmacy claims in a proprietary administrative claims database. Patients were excluded if they received either drug during the 180 days prior to their index prescription or if they did not have continuous plan enrollment during this period and for at least 90 days following the index date. The probability of treatment discontinuation within the first 60 days of treatment was estimated. Time to treatment discontinuation was analyzed for the cohort of patients that remained on therapy > or =60 days as well as for subgroups of the cohort reaching either approved or maximum recommended doses of donepezil or rivastigmine. Treatment discontinuation was defined as either a stop of therapy (no prescription refill within 60 days of estimated completion of prior prescription) or a switch to an alternative AD drug. Kaplan-Meier survival and proportional hazard model analyses were performed. Proportion of days covered (PDC) by an AD therapy was also evaluated in each quarter during the first year of follow-up. RESULTS: Of the newly treated AD study population, 30.4% (171/563) of rivastigmine patients and 31.2% (583/1,871) of donepezil patients discontinued treatment within 60 days of starting therapy (P = 0.72). For the cohort of patients that remained on therapy > or =60 days, the mean time to treatment discontinuation was 331 days (95% confidence interval [CI], 307-355) for rivastigmine patients (n = 392) versus 337 days (95% CI, 322-352) for donepezil patients (n = 1288). The proportion of patients with a PDC > or =80% after 12 months of follow-up was 23% for the donepezil group and 19% for the rivastigmine group (P = 0.34). For the cohort subgroup that reached an approved dose, the mean time to treatment discontinuation was 346 days (95% CI, 318-374) for rivastigmine patients (n = 282) versus 338 days (95% CI, 323-353) for donepezil patients (n = 1,283). For the cohort subgroup that reached the maximum recommended dose, the mean time to treatment discontinuation was 396 days (95% CI, 343-449) for rivastigmine patients (n = 61) versus 364 days (95% CI, 344-384) for donepezil patients (n = 712). CONCLUSION: Newly treated AD patients in a usual care setting who initiate therapy with either rivastigmine or donepezil have similar levels of persistency with treatment.

Cost effectiveness of treatment of Parkinson's disease with entacapone in the United States.

OBJECTIVE: To determine the cost effectiveness of adjunctive therapy with entacapone versus standard treatment (levodopa) without entacapone for patients in the US with Parkinson's disease (PD) who experience 'off-time' (re-emergence of the symptoms of PD) while receiving levodopa. STUDY DESIGN: A Markov model was used to estimate 5-year costs and effectiveness of standard treatment with and without entacapone. METHODS: Probabilities, unit costs, resource utilisation data and utilities were obtained from published literature, clinical trial reports, a national database, and clinical experts. PD disability was measured using the daily proportion of off-time and Hoehn and Yahr scale scores. The analysis measured costs from a societal and third-party payer perspective, and effectiveness as gains in quality-adjusted life-years (QALYs) and years without progression to >25% off-time. RESULTS: From a societal perspective, entacapone therapy resulted in an incremental cost of US dollars 9327 per QALY gained compared with standard treatment. Treatment with entacapone also provided an additional 7.6 months with < or =25% off-time/day compared with standard treatment. Sensitivity analyses indicated that the model is sensitive to changes in rates of improvement/deterioration of off-time, and to the number of doses per day of levodopa with adjunctive entacapone. CONCLUSIONS: The addition of entacapone to standard treatment for patients receiving levodopa who experience off-time provides additional QALYs and gain in time with minimal fluctuations. Results of this modelling exercise suggest that therapy with entacapone may be cost effective when compared with standard treatment for PD.

Impact of rivastigmine on costs and on time spent in caregiving for families of patients with Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) places a significant burden on health care systems worldwide. As new treatments are developed, their cost-effectiveness is often assessed to help health care professionals make informed decisions. In addition to the more common practice of assessing direct medical costs, indirect costs, including time spent in caregiving, should be evaluated. METHODS: This study examined the potential effects of the dual cholinesterase inhibitor rivastigmine (Exelon) on caregivers of patients with AD. Results from two 26-week, placebo-controlled trials have demonstrated the clinically relevant and statistically significant efficacy of rivastigmine (6-12 mg/day) compared to placebo, on cognition, activities of daily living, and global functioning. By delaying progression of AD, significant savings in caregiver burden are anticipated, as measured by time spent caregiving and its related costs. Data collected in a prospective, observational study of AD patients and their caregivers were used to establish the relationship between disease severity (based on Mini-Mental State Examination [MMSE] score) and time spent caregiving (according to the 5-item Caregivers Activity Survey score). A significant correlation was observed between the two scores (N = 43, r = -.56, p < .0001), demonstrating that more time for supervision from caregivers is required as the disease progresses. This finding was used to estimate the reduced caregiver burden resulting from the delay in disease progression that was demonstrated with use of rivastigmine. RESULTS: Over a 2-year period, the reduction in time spent in caregiving reached 691 hours for caregivers of patients with mild AD (MMSE score 21-30), resulting in a total savings of approximately 11,253 dollars. Treatment of patients with moderately severe AD was also evaluated. The trend was similar but the impact was less, suggesting an economic benefit to early therapy. CONCLUSION: Early diagnosis and a pharmacologic intervention that allows the patients to remain at home longer by delaying disease progression would have a beneficial impact on patients, caregivers, and payers, and should therefore be encouraged through initiatives designed to identify and treat patients early in the course of disease.