Update on LEQEMBI Investigational Subcutaneous Formulation TOKYO, Oct. 15, 2023 /PRNewswire/ -- Eisai Co. Ltd (Headquarters: Tokyo, CEO: Haruo Naito, "Eisai") announced today that the company will present new data from the phase 3 Clarity AD study for its Alzheimer's disease (AD) treatment LEQEMBI ® (lecanemab-irmb) 100 mg/mL injection for intravenous use and new data on the subcutaneous formulation in development at the 16th annual Clinical Trials on Alzheimer's Disease (CTAD) conference. The conference will be held in Boston, Massachusetts, United States and virtually from October 24 to 27, 2023. In addition to the data presented on Eisai's anti-amyloid beta (Aβ) protofibril* antibody LEQEMBI, phase 1 data for E2511, an investigational tropomyosin receptor Kinase A (TrkA) positive allosteric modulator (PAM), will be presented as well as other research from the company's AD pipeline. At the conference, Eisai will present data and research in five oral and ten poster presentations. BioArctic will give an oral presentation on lecanemab. U.S. journalists may experience the full interactive Multichannel News Release here: https://www.multivu.com/players/English/9211051-eisai-at-ctad2023/
In a late-breaking symposium on October 25 from 17:25-18:05 EDT, Eisai will present the latest data from the Clarity AD optional tau PET longitudinal substudy. The presentation will include a post-hoc analysis of the low and intermediate + high-tau subgroups, with the low-tau subgroup representing early stages of disease studied specifically in the phase 3 core study, and the open-label extension study. An update on the investigational subcutaneous formulation, including interim safety and effect on amyloid in the brain measured by amyloid PET, will be provided. Distinguished faculty members Christopher van Dyck M.D., Keith Johnson M.D. and Reisa Sperling M.D. will discuss the findings in a panel led by Michael Irizarry, M.D., MPH, Eisai. A live webcast of this symposium can be viewed on the Eisai Co., Ltd. website. "Alzheimer's disease is a progressive and relentless condition that requires early diagnosis1,2,3 and continued treatment. LEQEMBI supports neuronal function in Alzheimer's disease1,4,5 by clearing highly toxic protofibrils3,4 that can continue to cause neuronal injury and death well after plaques are cleared,"5,6,7,8 said Michael Irizarry, MD, MPH, Senior Vice President, Clinical Research, Neurology, Deputy Chief Clinical Officer, Clinical Evidence Generation, Eisai. "We look forward to sharing the new LEQEMBI low-tau subgroup data and subcutaneous data at CTAD 2023." Other major oral presentations include:
E2511, a novel TrkA modulator, engages its CNS cholinergic target in a phase 1 clinical study (OC34). Novel CSF tau biomarkers can be used for disease staging of sporadic Alzheimer's disease (OC2).
The full list of presentations about Eisai assets and research follows. Late Breaking Symposium 4
The Symposium title: Lecanemab for Early Alzheimer's Disease: Long-Term Outcomes, Predictive Biomarkers and Novel Subcutaneous Administration from 17:25 to 18:05 EDT on October 25, 2023. This release discusses investigational uses of agents in development and is not intended to convey conclusions about efficacy or safety. There is no guarantee that such investigational agents will successfully complete clinical development or gain health authority approval.
One of the AD pathological features is the accumulation of clusters (plaques) of amyloid beta (Aβ) in the brain. The formation of these plaques is the result of a continuous process by which individual Aβ proteins join together, latching onto each other, one at a time, like adding links to a chain.9 In the early part of this process these small chains of Aβ are soluble and are toxic to the nerves within the brain.10,11 The most toxic of the soluble chains is called a protofibril.3 Protofibrils are believed to contribute to the brain injury that occurs with AD and are considered to be the most toxic form of Aβ, having a primary role in the cognitive decline associated with this progressive, debilitating condition.1,2 Protofibrils cause injury to neurons in the brain, which in turn, can negatively impact cognitive function via multiple mechanisms, not only increasing the development of insoluble Aβ plaques but also increasing direct damage to brain cell membranes and the connections that transmit signals between nerve cells or nerve cells and other cells. It is believed the reduction of protofibrils may prevent the progression of AD by reducing damage to neurons in the brain and cognitive dysfunction.12 Amyloid Related Imaging Abnormalities
ARIA Monitoring and Dose Management Guidelines
Obtain recent baseline brain magnetic resonance imaging (MRI) prior to initiating treatment with LEQEMBI. Obtain an MRI prior to the 5th, 7th and 14th infusions. Recommendations for dosing in patients with ARIA-E and ARIA-H depend on clinical symptoms and radiographic severity. Depending on ARIA severity, use clinical judgment in considering whether to continue dosing, temporarily discontinue treatment, or permanently discontinue LEQEMBI. Enhanced clinical vigilance for ARIA is recommended during the first 14 weeks of treatment with LEQEMBI. If a patient experiences symptoms suggestive of ARIA, clinical evaluation should be performed, including MRI if indicated. If ARIA is observed on MRI, careful clinical evaluation should be performed prior to continuing treatment. There is no experience in patients who continued dosing through symptomatic ARIA-E or through asymptomatic, but radiographically severe, ARIA-E. There is limited experience in patients who continued dosing through asymptomatic but radiographically mild to moderate ARIA-E. There are limited data in dosing patients who experienced recurrent ARIA-E.
In Study 2, symptomatic ARIA occurred in 3% (29/898) of LEQEMBI-treated patients. Serious symptoms associated with ARIA were reported in 0.7% (6/898) of patients treated with LEQEMBI. Clinical symptoms associated with ARIA resolved in 79% (23/29) of patients during the period of observation. Including asymptomatic radiographic events, ARIA was observed in LEQEMBI: 21% (191/898); placebo: 9% (84/897). ARIA-E was observed in LEQEMBI: 13% (113/898); placebo: 2% (15/897). ARIA-H was observed in LEQEMBI: 17% (152/898); placebo: 9% (80/897). There was no increase in isolated ARIA-H for LEQEMBI vs placebo. ApoE ε4 Carrier Status and Risk of ARIA In Study 2, 16% (141/898) of patients in the LEQEMBI arm were ApoE ε4 homozygotes, 53% (479/898) were heterozygotes, and 31% (278/898) were noncarriers. The incidence of ARIA was higher in ApoE ε4 homozygotes (LEQEMBI: 45%; placebo: 22%) than in heterozygotes (LEQEMBI: 19%; placebo: 9%) and noncarriers (LEQEMBI: 13%; placebo: 4%). Among patients treated with LEQEMBI, symptomatic ARIA-E occurred in 9% of ApoE ε4 homozygotes compared with 2% of heterozygotes and 1% noncarriers. Serious events of ARIA occurred in 3% of ApoE ε4 homozygotes, and approximately 1% of heterozygotes and noncarriers. The recommendations on management of ARIA do not differ between ApoE ε4 carriers and noncarriers.
The majority of ARIA-E radiographic events occurred early in treatment (within the first 7 doses), although ARIA can occur at any time and patients can have more than 1 episode. The maximum radiographic severity of ARIA-E in patients treated with LEQEMBI was mild in 4% (37/898), moderate in 7% (66/898), and severe in 1% (9/898). Resolution on MRI occurred in 52% of ARIA-E patients by 12 weeks, 81% by 17 weeks, and 100% overall after detection. The maximum radiographic severity of ARIA-H microhemorrhage in LEQEMBI-treated patients was mild in 9% (79/898), moderate in 2% (19/898), and severe in 3% (28/898) of patients; superficial siderosis was mild in 4% (38/898), moderate in 1% (8/898) , and severe in 0.4% (4/898). Among LEQEMBI-treated patients, the rate of severe radiographic ARIA-E was highest in ApoE ε4 homozygotes 5% (7/141), compared to heterozygotes 0.4% (2/479) or noncarriers 0% (0/278). Among LEQEMBI-treated patients, the rate of severe radiographic ARIA-H was highest in ApoE ε4 homozygotes 13.5% (19/141), compared to heterozygotes 2.1% (10/479) or noncarriers 1.1% (3/278). Concomitant Antithrombotic Medication:
In Study 2, baseline use of antithrombotic medication (aspirin, other antiplatelets, or anticoagulants) was allowed if the patient was on a stable dose. The majority of exposures to antithrombotic medications were to aspirin. Antithrombotic medications did not increase the risk of ARIA with LEQEMBI. The incidence of intracerebral hemorrhage was 0.9% (3/328 patients) in patients taking LEQEMBI with a concomitant antithrombotic medication at the time of the event compared to 0.6% (3/545 patients) in those who did not receive an antithrombotic. Patients taking LEQEMBI with an anticoagulant alone or combined with an antiplatelet medication or aspirin had an incidence of intracerebral hemorrhage of 2.5% (2/79 patients) compared to none in patients who received placebo. Because intracerebral hemorrhages >1 cm in diameter have been observed in patients taking LEQEMBI, additional caution should be exercised when considering the administration of anticoagulants or a thrombolytic agent (e.g., tissue plasminogen activator) to a patient already being treated with LEQEMBI. Hypersensitivity Reactions
Infusion-Related Reactions
In Study 2, infusion-related reactions were observed in LEQEMBI: 26% (237/898); placebo: 7% (66/897), and the majority of cases in LEQEMBI-treated patients (75%, 178/237) occurred with the first infusion. Infusion-related reactions were mostly mild (69%) or moderate (28%) in severity. Infusion-related reactions resulted in discontinuations in 1% (12/898) of LEQEMBI-treated patients. Symptoms of infusion-related reactions included fever and flu-like symptoms (chills, generalized aches, feeling shaky, and joint pain), nausea, vomiting, hypotension, hypertension, and oxygen desaturation. In the event of an infusion-related reaction, the infusion rate may be reduced, or the infusion may be discontinued, and appropriate therapy initiated as clinically indicated. Prophylactic treatment with antihistamines, acetaminophen, nonsteroidal anti-inflammatory drugs, or corticosteroids prior to future infusions may be considered. In Study 2, the most common adverse reactions leading to discontinuation of LEQEMBI was ARIA-H microhemorrhages that led to discontinuation in 2% (15/898) of patients treated with LEQEMBI compared to for LEQEMBI, including Boxed WARNING. Please see full Prescribing Information, including Boxed WARNING in the United States.
Eisai has also submitted applications for approval of lecanemab in EU, China, Canada, Great Britain, Australia, Switzerland, South Korea and Israel. In China and Israel, the applications have been designated for priority review, and in Great Britain, lecanemab has been designated for the Innovative Licensing and Access Pathway (ILAP), which aims to reduce the time to market for innovative medicines. Eisai has completed a lecanemab subcutaneous bioavailability study, and subcutaneous dosing is currently being evaluated in the Clarity AD (Study 301) open-label extension (OLE). A maintenance dosing regimen has been evaluated as part of Study 201. Since July 2020 the Phase 3 clinical study (AHEAD 3-45) for individuals with preclinical AD, meaning they are clinically normal and have intermediate or elevated levels of amyloid in their brains, is ongoing. AHEAD 3-45 is conducted as a public-private partnership between the Alzheimer's Clinical Trial Consortium that provides the infrastructure for academic clinical trials in AD and related dementias in the U.S, funded by the National Institute on Aging, part of the National Institutes of Health, Eisai and Biogen. Since January 2022, the Tau NexGen clinical study for Dominantly Inherited AD (DIAD), that is conducted by Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU), led by Washington University School of Medicine in St. Louis, is ongoing and includes lecanemab as the backbone anti-amyloid therapy. E2511 is Eisai' s in-house discovered and developed investigational novel molecule that directly binds to tropomyosin receptor kinase A (TrkA); a nerve growth factor (NGF) located on the neural cell membrane. E2511 could potentially promote recovery and synaptic remodeling of damaged cholinergic neurons. A Phase 1 study for E2511 is underway. Eisai and Biogen have been collaborating on the joint development and commercialization of AD treatments since 2014. Eisai serves as the lead of lecanemab development and regulatory submissions globally with both Eisai and Biogen co-commercializing and co-promoting the product and Eisai having final decision-making authority. In Japan, Eisai and Biogen Japan will co-promote lecanemab, with Eisai distributing the product as the Marketing Authorization Holder. Since 2005, Eisai and BioArctic have had a long-term collaboration regarding the development and commercialization of AD treatments. Eisai obtained the global rights to study, develop, manufacture and market LEQEMBI for the treatment of AD pursuant to an agreement with BioArctic in December 2007. The development and commercialization agreement on the antibody LEQEMBI back-up was signed in May 2015. LEQEMBI US Prescribing Information under Traditional Approval Alzheimer's Association, Facts & Figures 2023. https://www.alz.org/media/Documents/alzheimers-facts-and-figures.pdf Accessed October 12, 2023.
Hampel, H., Hardy, J., Blennow, K. et al. The Amyloid-β Pathway in Alzheimer's Disease. Mol Psychiatry. 2021;26:5481–5503. https://doi.org/10.1038/s41380-021-01249-0 Ono K, Tsuji M. Protofibrils of Amyloid-β are Important Targets of a Disease-Modifying Approach for Alzheimer's Disease. Int J Mol Sci. 2020;21(3):952. Doi: 10.3390/ijms21030952. PMID: 32023927; PMCID: PMC7037706. Söderberg L, et al. Lecanemab, Aducanumab, and Gantenerumab — Binding Profiles to Different Forms of Amyloid–Beta Might Explain Efficacy and Side Effects in Clinical Trials for Alzheimer's Disease. Neurotherapeutics. 2023;20:195–206 https://doi.org/10.1007/s13311-022-01308-6 Accessed October 12, 2023. Hartley DM, Walsh DM, Ye CP, Diehl T, Vasquez S, Vassilev PM, Teplow DB, Selkoe DJ. Protofibrillar intermediates of amyloid beta-protein induce acute electrophysiological changes and progressive neurotoxicity in cortical neurons. J Neurosci. 1999;19(20):8876-84. doi: 10.1523/JNEUROSCI.19-20-08876.1999. PMID: 10516307; PMCID: PMC6782787. Alzheimer's Association. (2022). Brain Tour Part 2 - Alzheimer's Effect. Retrieved September 27, 2023, from https://www.alz.org/alzheimers-dementia/what-is-alzheimers/brain_tour_part_2
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Habashi M., Vulta S., Tripathi K., et al. Early diagnosis and treatment of Alzheimer's disease by targeting toxic soluble Aβ oligomers. Biophysics and Computational Biology. 2022;10.1073. https://www.pnas.org/doi/epdf/10.1073/pnas.2210766119 Amin L, Harris DA. Aβ receptors specifically recognize molecular features displayed by fibril ends and neurotoxic oligomers. Nat Commun. 2021;12:3451. doi:10.1038/s41467-021-23507-z