Physician preferences for bone metastasis drug therapy in Canada

BACKGROUND

Currently in Canada, several bone-targeted agents (btas) with varying characteristics are available for the prevention of skeletal-related events (sres) in patients with bone metastasis secondary to solid tumours. In the present study, we evaluated the preferences of physicians in Canada for the various attributes of the available btas.

METHODS

Physicians treating patients with bone metastasis from solid tumours were invited to complete an online discrete-choice experiment. Respondents were asked to choose between pairs of hypothetical medications for virtual patients. Each hypothetical medication was described based on predefined key attributes: time until first sre, time until worsening of pain, medication-related annual risk of osteonecrosis of the jaw (onj), medication-related annual risk of renal impairment, and mode of administration. A random-parameters logit model was used to analyze the choices between hypothetical medications and thus infer physician preferences for medication attributes.

RESULTS

Responses from the 200 physicians who completed the discrete-choice experiment suggested that months until first sre, risk of renal impairment, and months until worsening of pain were considered the most important attributes affecting choice of bta. The annual risk of onj was considered the least important attribute.

CONCLUSIONS

When making treatment decisions about the choice of bta for patients with bone metastasis from solid tumours, delaying sres and worsening of pain, and reducing the risk of renal impairment are primary considerations for physicians in Canada.

A discrete-choice experiment of United Kingdom patients' willingness to risk adverse events for improved function and pain control in osteoarthritis

OBJECTIVE

To assess patient preferences for treatment-related benefits and risks associated with the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in the management of osteoarthritis (OA).

DESIGN

Using a chronic-illness panel in the United Kingdom, patients 45 years or older with a self-reported diagnosis of OA were eligible to participate in the study. Patient preferences were assessed using a discrete-choice experiment that compared hypothetical treatment profiles of benefits and risks consistent with NSAID use. Benefit outcomes (ambulatory pain, resting pain, stiffness, and difficulty doing daily activities) were presented on a 0-to-100 mm scale. Risk outcomes (bleeding ulcer, stroke, and myocardial infarction [MI]) were expressed as probabilities over a fixed time period. Each patient answered 10 choice tasks comparing different treatment profiles. Preference weights were estimated using a random-parameters logit model.

RESULTS

Final sample included 294 patients. Patients ranked reductions in ambulatory pain and difficulty doing daily activities (both: 6.32; 95% confidence interval [CI]: 5.0-7.6) as the most important benefit outcomes, followed by reductions in resting pain (2.80; 95% CI: 1.8-3.8) and stiffness (2.65; 95% CI: 0.9-4.4). Incremental changes (3%) in the risk of MI or stroke were assessed as the most important risk outcomes (10.00; 95% CI: 8.2-11.8; and 8.90; 95% CI: 7.3-10.5, respectively).

CONCLUSION

Patients ranked ambulatory pain as a more important benefit than resting pain; likely due to its impact on ability to do daily activities. For a 25-mm reduction, patients were willing to accept four times the risk of MI in ambulatory pain vs resting pain.

Treatment preferences and medication adherence of people with Type 2 diabetes using oral glucose-lowering agents

AIMS

Medication non-adherence is particularly common in patients with Type 2 diabetes. We constructed a discrete-choice experiment to examine the relative importance of oral glucose-lowering medication features and to estimate the likely effect of effectiveness and side effects on medication adherence in patients with Type 2 diabetes in the UK and the USA.

METHODS

Preferences were elicited using a cross-sectional, web-enabled survey. Patients with a self-reported physician-made diagnosis of Type 2 diabetes, who were currently taking oral glucose-lowering medications were recruited through an existing online chronic-disease panel. In each discrete-choice question, patients were asked to choose between two hypothetical medication alternatives, each defined by improvement in glycated haemoglobin, frequency of mild-to-moderate hypoglycaemia, water retention, weight gain, mild stomach upset and medication-related cardiovascular risk. Patients were also asked to indicate how likely they would be to miss or skip doses of each hypothetical medication.

RESULTS

Two hundred and four patients in the UK and 203 patients in the USA completed the survey. Preferences did not differ between the two countries. Overall, glucose control was the most important medication feature, followed by medication-related cardiovascular risk and weight gain, respectively. Water retention was not important to patients. Weight gain and cardiovascular risk had significant negative effects on likely medication adherence.

CONCLUSIONS

While patients with Type 2 diabetes believe glucose control is important, medication side effects and risks influence patients' treatment choices. Medication-related weight gain and cardiovascular risk are significant predictors of likely medication non-adherence.

Potential savings in the cost of caring for Alzheimer's disease. Treatment with rivastigmine

OBJECTIVE

To estimate savings in the cost of caring for patients with Alzheimer's disease (AD) during 6 months, 1 year and 2 years of treatment with rivastigmine. An intermediate objective was to estimate the relationship between disease progression and institutionalisation.

DESIGN AND SETTING

We assessed the relationship between Mini-Mental State Examination (MMSE) score and institutionalisation using a piecewise Cox proportional hazard model. To estimate cost savings from treatments lasting 6 months, 1 year and 2 years, estimates of the probability of institutionalisation were integrated with data from two 6-month phase III clinical trials of rivastigmine and a hazard model of disease progression.

MAIN OUTCOME MEASURES AND RESULTS

Our data suggest that savings in the overall cost of caring for patients with mild and moderate AD can be as high as $US4839 per patient after 2 years of treatment. Furthermore, the probability of institutionalisation increases steadily as MMSE score falls. Among our study individuals, age, race, level of education and marital status were significant predictors of institutionalisation, whereas gender had little effect.

CONCLUSIONS

Using rivastigmine to treat AD results in a delay in disease progression for patients who begin treatment during the mild or moderate stages of the disease. By delaying the probability that a patient will be institutionalised, the cost of caring for AD patients can be significantly reduced.

Savings in the cost of caring for patients with Alzheimer's disease in Canada: an analysis of treatment with rivastigmine

OBJECTIVE

To estimate per-patient potential cost savings using rivastigmine in the treatment of Alzheimer's disease (AD) in Canada.

BACKGROUND

In recent years, new members of a class of pharmaceuticals known as cholinesterase inhibitors have been introduced for the treatment of patients with AD. Two recent studies conducted in the United Kingdom and the United States estimated potential cost savings from the new cholinesterase inhibitor rivastigmine. The present study combined the disease-progression model used in those 2 studies with Canadian costs to estimate per-patient potential savings resulting from the treatment of AD in Canada.

METHODS

Efficacy data from 2 pivotal, phase III clinical trials of rivastigmine were used in a hazard model of disease progression to estimate long-term differences in cognitive functioning between patients receiving rivastigmine and patients receiving no treatment. We used the Mini-Mental State Examination (MMSE) score as our measure of disease progression. We also used Canadian costs of AD care, estimated as a function of MMSE score, to estimate cost savings experienced by treated patients compared with patients receiving no treatment. All costs and cost savings are presented in 1997 Canadian dollars. We used a societal perspective in this analysis.

RESULTS

Rivastigmine was estimated to delay the transition to more severe stages of AD by up to 188 days for patients with mild AD after 2 years of treatment. For patients with mild-to-moderate and moderate disease, this delay was estimated to be 106 and 44 days, respectively. For patients with the mild stage of AD, estimated average daily cost savings (excluding the cost of rivastigmine) ranged from Can $0.45 per patient per day at 6 months to Can $6.44 per patient per day after 2 years of treatment. For all patients, these estimated average daily cost savings ranged from a low of Can $0.71 per patient per day after 6 months of treatment to a high of Can $4.93 per patient per day after 2 years.

CONCLUSION

On average, treatment with rivastigmine yields savings in the direct cost of caring for AD patients that exceed the cost of the drug after 2 years of treatment.