Protocol of a randomised delayed-start double-blind placebo-controlled multi-centre trial for Levodopa in EArly Parkinson's disease: the LEAP-study

An International Multi-Stakeholder Delphi Survey Study on the Design of Disease Modifying Parkinson's Disease Trials

BACKGROUND

Design of disease modification (DM) trials for Parkinson's disease (PD) is challenging. Successful delivery requires a shared understanding of priorities and practicalities.

OBJECTIVE

To seek stakeholder consensus on phase 3 trials' overall goals and structure, inclusion criteria, outcome measures, and trial delivery and understand where perspectives differ.

METHODS

An international expert panel comprising people with Parkinson's (PwP), care partners (CP), clinical scientists, representatives from industry, funders and regulators participated in a survey-based Delphi study. Survey items were informed by a scoping review of DM trials and PwP input. Respondents scored item agreement over 3 rounds. Scores and reasoning were summarized by participant group each round until consensus, defined as≥70% of at least 3 participant groups falling within the same 3-point region of a 9-point Likert scale.

RESULTS

92/121 individuals from 13 countries (46/69 PwP, 13/18 CP, 20/20 clinical scientists, representatives from 8/8 companies, 4/5 funders, and 1/1 regulator) completed the study. Consensus was reached on 14/31 survey items: 5/8 overall goals and structure, 1/8 Eligibility criteria, 7/13 outcome measures, and 1/2 trial delivery items. Extent of stakeholder endorsement for 428 reasons for scores was collated across items.

CONCLUSIONS

This is the first systematic multi-stakeholder consultation generating a unique repository of perspectives on pivotal aspects of DM trial design including those of PwP and CP. The panel endorsed outcomes that holistically measure PD and the importance of inclusive trials with hybrid delivery models. Areas of disagreement will inform mitigating strategies of researchers to ensure successful delivery of future trials.

Exploration of whether socioeconomic factors affect the results of priority setting partnerships: updating the top 10 research priorities for the management of Parkinson's in an international setting

OBJECTIVES

Explore whether socioeconomic differences of patients affect the prioritisation of pre-existing research questions and explore the agreement between healthcare professionals (HCP) and patients in priority setting partnerships (PSPs).

DESIGN AND SETTING

Prospective, three centre survey across UK (400 participants), Tuebingen (176 participants) and Luxembourg (303 participants). People with Parkinson's (PwP), research participants, relatives and HCP associated with three Parkinson's cohort studies were invited to participate, along with linked centres (clinical care settings, research groups, charities). Responders were encouraged to pass on the survey to friends/families/carers.

METHODS

The survey involved rating the importance of research questions on a Likert scale, allowing for the generation of one new question participants felt was particularly important. Collection of demographic information allowed for comparisons of priorities across a range of socioeconomic variables; the top 10 research priorities for each group were then compared. Questions added by participants were subject to a thematic analysis.

RESULTS

879 participants completed the survey (58% PwP, 22% family/friends, 13% HCP, 4% carers). Finding the best form of physiotherapy for PwP was the number one priority across the majority of analyses. HCP were the only subgroup not to place physiotherapy in the top 10. Factors most likely to affect prioritisation in PwP included educational level, presence of carer support and disease duration. There was little difference between other socioeconomic categories.

CONCLUSIONS

Socioeconomic factors modestly influenced some research priority ratings but did not significantly affect the top priority in most comparisons. Future studies must ensure patients from a range of socioeconomic backgrounds are recruited, ensuring results generalisable to the public while also identifying any key disparities in prioritisation. PSP should also take care that HCP do not skew results during prioritisation of questions, as in this study the most important priority to patients was not identified by professionals.

Review of the recruitment process for a large investigator-initiated trial in early Parkinson’s disease

Introduction

Organizing and executing a large clinical trial is a complex process, and often recruitment targets are not met. We describe the organization of the Levodopa in the Early Parkinson’s disease (LEAP) trial and the results of an external assessment of the recruitment process.

Methods

Several strategies were used to ensure that recruitment for the trial was effective and efficient. We analyzed the patterns in referrals, inclusions, and non-inclusions to investigate whether there were bottlenecks in the referral and inclusion process. For the external assessment of the recruitment process, the QuinteT Recruitment Intervention (QRI-Two) was used retrospectively, focusing on finding possible issues impeding recruitment that are less easily recognized.

Results

Recruitment took 57 months, which was 27 months longer than initially expected. 6.8% of the estimated eligible patients in the Netherlands were included. The number of referrals differed widely between participating centers and regions in the Netherlands, with the region of the principal study center having the most referrals. Reasons of exclusion varied across regions, as in some regions more patients already started, wanted to start, or did not want to start with Parkinson medication compared to other regions.

Discussion

Executing a large, investigator-initiated clinical trial on a limited budget still remains possible by focusing on minimizing administrative and organizational procedures. Our study suggests that centers with closer institutional ties to a principal study center tend to have a higher referral rate. The review of the LEAP trial recruitment strategies and data using the QRI-Two suggested that the variations in referrals and reasons of non-inclusion could indicate the presence of issues related to clinical equipoise, patient eligibility, or study presentation. Integrating a recruitment intervention could have explored issues with study presentation and equipoise that might have increased recruitment efficiency.

Trial registration

ISRCTN ISRCTN30518857. The registration was initiated on 02/08/2011 and finalized on 25/08/2011. Recruitment started on 17/08/2011, after the initiation of public registration.

Cost-Effectiveness and Cost-Utility of Early Levodopa in Parkinson's Disease

BACKGROUND

In the Levodopa in EArly Parkinson's disease (LEAP) study, 445 patients were randomized to levodopa/carbidopa 100/25 mg three times per day for 80 weeks (early-start) or placebo for 40 weeks followed by levodopa/carbidopa 100/25 mg three times per day for 40 weeks (delayed-start).

OBJECTIVE

This paper reports the results of the economic evaluation performed alongside the LEAP-study.

METHODS

Early-start treatment was evaluated versus delayed-start treatment, in which the cost-effectiveness analysis (CEA) and the cost-utility analysis (CUA) were performed from the societal perspective, including health care costs among providers, non-reimbursable out-of-pocket expenses of patients, employer costs of sick leave, and lowered productivity while at work. The outcome measure for the CEA was the extra cost per unit decrease on the Unified Parkinson's Disease Rating Scale 80 weeks after baseline. The outcome measure for the CUA was the extra costs per additional quality adjusted life year (QALY) during follow-up.

RESULTS

212 patients in the early-start and 219 patients in the delayed-start group reported use of health care resources. With savings of € 59 per patient (BCa 95% CI: -829, 788) in the early-start compared to the delayed-start group, societal costs were balanced. The early-start group showed a mean of 1.30 QALYs (BCa 95% CI: 1.26, 1.33) versus 1.30 QALYs (BCa 95% CI: 1.27, 1.33) for the delayed-start group. Because of this negligible difference, incremental cost-effectiveness and cost-utility ratios were not calculated.

CONCLUSION

From an economic point of view, this study suggests that early treatment with levodopa is not more expensive than delayed treatment with levodopa.

Earlier Dopaminergic Treatment in Parkinson's Disease Is Not Associated With Improved Outcomes

Background

The appropriate timing of dopaminergic treatment initiation in Parkinson's disease (PD) remains a matter of debate. The primary objective of this study was to determine whether earlier initiation of treatment was associated with less worsening of total UPDRS scores over 48 months.

Methods

We performed a secondary analysis of data from the CALM-PD (Comparison of the Agonist Pramipexole With Levodopa on Motor Complications of Parkinson's Disease) trial to examine the associations between years since diagnosis and 48-month changes in total and component UPDRS scores, Parkinson's Disease Quality of Life Scale (PDQUALIF) score, and the EuroQol-5D visual analogue scale (VAS) score.

Results

There were no associations between years since PD diagnosis and 48-month changes in total UPDRS, component UPDRS scores, PDQUALIF score, or EuroQol-5D VAS score.

Conclusion

Earlier treatment was not associated with improved long-term outcomes in this secondary analysis. Prospective studies are required to determine the appropriate timing of initiation of dopaminergic treatment to inform clinical practice.

Randomized Delayed-Start Trial of Levodopa in Parkinson's Disease

BACKGROUND

Levodopa is the main treatment for symptoms of Parkinson's disease. Determining whether levodopa also has a disease-modifying effect could provide guidance as to when in the course of the disease the treatment with this drug should be initiated.

METHODS

In a multicenter, double-blind, placebo-controlled, delayed-start trial, we randomly assigned patients with early Parkinson's disease to receive levodopa (100 mg three times per day) in combination with carbidopa (25 mg three times per day) for 80 weeks (early-start group) or placebo for 40 weeks followed by levodopa in combination with carbidopa for 40 weeks (delayed-start group). The primary outcome was the between-group difference in the mean change from baseline to week 80 in the total score on the Unified Parkinson's Disease Rating Scale (UPDRS; scores range from 0 to 176, with higher scores signifying more severe disease). Secondary analyses included the progression of symptoms, as measured by the UPDRS score, between weeks 4 and 40 and the noninferiority of early initiation of treatment to delayed initiation between weeks 44 and 80, with a noninferiority margin of 0.055 points per week.

RESULTS

A total of 445 patients were randomly assigned: 222 to the early-start group and 223 to the delayed-start group. The mean (±SD) UPDRS score at baseline was 28.1±11.4 points in the early-start group and 29.3±12.1 points in the delayed-start group. The change in UPDRS score from baseline to week 80 was -1.0±13.1 points and -2.0±13.0 points, respectively (difference, 1.0 point; 95% confidence interval [CI], -1.5 to 3.5; P=0.44); this finding of no significant between-group difference at week 80 implies that levodopa had no disease-modifying effect. Between weeks 4 and 40, the rate of progression of symptoms, as measured in UPDRS points per week, was 0.04±0.23 in the early-start group and 0.06±0.34 in the delayed-start group (difference, -0.02; 95% CI, -0.07 to 0.03). The corresponding rates between weeks 44 and 80 were 0.10±0.25 and 0.03±0.28 (difference, 0.07; two-sided 90% CI, 0.03 to 0.10); the difference in the rate of progression between weeks 44 and 80 did not meet the criterion for noninferiority of early receipt of levodopa to delayed receipt. The rates of dyskinesia and levodopa-related fluctuations in motor response did not differ significantly between the two groups.

CONCLUSIONS

Among patients with early Parkinson's disease who were evaluated over the course of 80 weeks, treatment with levodopa in combination with carbidopa had no disease-modifying effect. (Funded by the Netherlands Organization for Health Research and Development and others; LEAP Current Controlled Trials number, ISRCTN30518857 .).