Opicapone versus entacapone: Head-to-head retrospective data-based comparison of healthcare resource utilization in people with Parkinson's disease new to catechol-O-methyltransferase (COMT) inhibitor treatment.

BACKGROUND AND PURPOSE: Motor fluctuations are a significant driver of healthcare resource utilization (HCRU) in people with Parkinson's disease (pwPD). A common management strategy is to include catechol-O-methyltransferase (COMT) inhibition with either opicapone or entacapone in the levodopa regimen. However, to date, there has been a lack of head-to-head data comparing the two COMT inhibitors in real-world settings. The aim of this study was to evaluate changes in HCRU and effect on sleep medications when opicapone was initiated as first COMT inhibitor versus entacapone. METHODS: In this retrospective cohort study, we assessed HCRU outcomes in pwPD naïve to COMT inhibition via UK electronic healthcare records (Clinical Practice Research Datalink and Hospital Episodes Statistics databases, June 2016 to December 2019). HCRU outcomes were assessed before (baseline) and after COMT inhibitor prescription at 0-6 months, 7-12 months and 13-18 months. Opicapone-treated pwPD were algorithm-matched (1:4) to entacapone-treated pwPD. RESULTS: By 6 months, treatment with opicapone resulted in 18.5% fewer neurology outpatient visits compared to entacapone treatment; this effect was maintained until the last follow-up (18 months). In the opicapone group, the mean levodopa equivalent daily dose decreased over the first year and then stabilized, whereas the entacapone-treated group showed an initial decrease in the first 6 months followed by a dose increase between 7 and 18 months. Neither COMT inhibitor had a significant impact on sleep medication use. CONCLUSIONS: This head-to-head study is the first to demonstrate, using 'real-world' data, that initiating COMT inhibition with opicapone is likely to decrease the need for post-treatment HCRU versus initiation of COMT inhibition with entacapone.

The Cost Effectiveness of Levodopa-Carbidopa Intestinal Gel in the Treatment of Advanced Parkinson's Disease in England.

BACKGROUND: Parkinson's disease is a progressive neurodegenerative disease, which significantly impacts patients' quality of life and is associated with high treatment and direct healthcare costs. In England, levodopa/carbidopa intestinal gel (LCIG) is indicated for the treatment of levodopa-responsive advanced Parkinson's disease with troublesome motor fluctuations when available combinations of medicinal products are unsatisfactory. OBJECTIVE: We aimed to determine the cost effectiveness of LCIG compared to the standard of care for patients with advanced Parkinson's disease in England, using real-world data. METHODS: A Markov model was adapted from previous published studies, using the perspective of the English National Health System and Personal and Social Services to evaluate the cost effectiveness of LCIG compared to standard of care in patients with advanced Parkinson's disease over a 20-year time horizon. The model comprised 25 health states, defined by a combination of the Hoehn and Yahr scale, and waking time spent in OFF-time. The base case considered an initial cohort of patients with an Hoehn and Yahr score of ≥ 3, and > 4 h OFF-time. Standard of care comprised standard oral therapies, and a proportion of patients were assumed to be treated with subcutaneous apomorphine infusion or injection in addition to oral therapies. Efficacy inputs were based on LCIG clinical trials where possible. Resource use and utility values were based on results of a large-scale observational study, and costs were derived from the latest published UK data, valued at 2017 prices. The EuroQol five-dimensions-3-level (EQ-5D-3L) instrument was used to measure utilities. Costs and quality-adjusted life-years were discounted at 3.5%. Both deterministic and probabilistic sensitivity analyses were conducted. RESULTS: Total costs and quality-adjusted life-years gained for LCIG vs standard of care were £586,832 vs £554,022, and 2.82 vs 1.43, respectively. The incremental cost-effectiveness ratio for LCIG compared to standard of care was £23,649/quality-adjusted life-year. Results were sensitive to the healthcare resource utilisation based on real-world data, and long-term efficacy of LCIG. CONCLUSIONS: The base-case incremental cost-effectiveness ratio was estimated to be within the acceptable thresholds for cost effectiveness considered for England.

Soluble pre-fibrillar tau and ß-amyloid species emerge in early human Alzheimer's disease and track disease progression and cognitive decline.

Post-mortem investigations of human Alzheimer's disease (AD) have largely failed to provide unequivocal evidence in support of the original amyloid cascade hypothesis, which postulated deposition of ß-amyloid (Aß) aggregates to be the cause of a demented state as well as inductive to tau neurofibrillary tangles (NFTs). Conflicting evidence suggests, however, that Aß plaques and NFTs, albeit to a lesser extent, are present in a substantial subset of non-demented individuals. Hence, a range of soluble tau and Aß species has more recently been implicated as the disease-relevant toxic entities. Despite the incorporation of soluble proteins into a revised amyloid cascade hypothesis, a detailed characterization of these species in the context of human AD onset, progression and cognitive decline has been lacking. Here, lateral temporal lobe samples (Brodmann area 21) of 46 human cases were profiled via tau and Aß Western blot and native state dot blot protocols. Elevations in phospho-tau (antibodies: CP13, AT8 and PHF-1), pathological tau conformations (MC-1) and oligomeric tau (TOC1) agreed with medical diagnosis (non-AD cf. AD) and Braak stage classification (low, intermediate and high), alongside elevations in soluble Aß species (MOAB-2 and pyro-glu Aß) and a decline in levels of the amyloid precursor protein. Strong correlations were observed between individual Braak stages and multiple cognitive measures with all tau markers as well as total soluble Aß. In contrast to previous reports, SDS-stable Aß oligomers (*56) were not found to be reliable for all classifications and appeared likely to be a technical artefact. Critically, the robust predictive value of total soluble Aß was dependent on native state quantification. Elevations in tau and Aß within soluble fractions (Braak stage 2-3 cf. 0) were evident earlier than previously established in fibril-focused disease progression scales. Together, these data provide strong evidence that soluble forms of tau and Aß co-localise early in AD and are closely linked to disease progression and cognitive decline.

A novel retro-inverso peptide inhibitor reduces amyloid deposition, oxidation and inflammation and stimulates neurogenesis in the APPswe/PS1ΔE9 mouse model of Alzheimer's disease.

Previously, we have developed a retro-inverso peptide inhibitor (RI-OR2, rGffvlkGr) that blocks the in vitro formation and toxicity of the Aß oligomers which are thought to be a cause of neurodegeneration and memory loss in Alzheimer's disease. We have now attached a retro-inverted version of the HIV protein transduction domain 'TAT' to RI-OR2 to target this new inhibitor (RI-OR2-TAT, Ac-rGffvlkGrrrrqrrkkrGy-NH(2)) into the brain. Following its peripheral injection, a fluorescein-labelled version of RI-OR2-TAT was found to cross the blood brain barrier and bind to the amyloid plaques and activated microglial cells present in the cerebral cortex of 17-months-old APPswe/PS1ΔE9 transgenic mice. Daily intraperitoneal injection of RI-OR2-TAT (at 100 nmol/kg) for 21 days into 10-months-old APPswe/PS1ΔE9 mice resulted in a 25% reduction (p<0.01) in the cerebral cortex of Aß oligomer levels, a 32% reduction (p<0.0001) of ß-amyloid plaque count, a 44% reduction (p<0.0001) in the numbers of activated microglial cells, and a 25% reduction (p<0.0001) in oxidative damage, while the number of young neurons in the dentate gyrus was increased by 210% (p<0.0001), all compared to control APPswe/PS1ΔE9 mice injected with vehicle (saline) alone. Our data suggest that oxidative damage, inflammation, and inhibition of neurogenesis are all a downstream consequence of Aß aggregation, and identify a novel brain-penetrant retro-inverso peptide inhibitor of Aß oligomer formation for further testing in humans as a potential disease-modifying treatment for Alzheimer's disease.