Covid-19 pandemic disrupts clinical trials in Alzheimer’s disease
The pharmaceutical industry has been as affected as any other industry by the Covid-19 pandemic; most countries’ sites have put clinical trial studies on hold, due to the inability to have dosing and in-person clinic visits for treatment and prevention trials, and pharmaceutical companies are shifting their overall priorities away from some current indications, such as those focusing on Alzheimer’s disease, toward Covid-19, according to GlobalData, a leading data and analytics company.
In the Alzheimer’s pipeline, 19 drugs are in Phase III, 37 are in Phase II, and 38 are in Phase I of development. Targeting Aβ is the favored mechanism of action for disease-modifying therapies (DMTs) in the mid- and late-stage trials; currently, six of these drugs are in Phase III, including Roche’s gantenerumab, Biogen’s aducanumab, and Eisai’s BAN-2401, and six DMTs are in Phase II including Eli Lilly’s donanemab and Alzheon’s ALZ-801.
How does COVID-19 spread?
Because COVID-19 is a new virus, nobody has prior immunity to it, meaning the entire human population is prone to infection.
It primarily spreads via respiratory droplets when people cough or sneeze. Scientists have yet to understand how easily and sustainably the disease can spread among people. Based on available evidence, researchers do not think airborne spread is a major transmission route.
Individuals over age 60 are at the highest risk of developing a severe case of COVID-19, while children do not seem to be at a higher risk than adults.
There are currently no reports about how susceptible pregnant women may be to COVID-19 or about transmission of the virus through breast milk.
What are the symptoms of COVID-19?
Common symptoms of COVID-19 begin two to 14 days after exposure. They include fever, tiredness, and dry cough. Other symptoms include sputum production, shortness of breath, sore throat, headache, myalgia (muscle pain) or arthralgia (joint pain), chills, vomiting, and nasal congestion. Less frequent symptoms include diarrhea, hemoptysis (coughing up blood from the respiratory tract), and conjunctival congestion.
Most of these symptoms are usually mild, and about 80% of people who get the virus will typically recover without needing any special treatment. However, about 1 in 6 patients become seriously ill and develop breathing difficulties.
Not all pharmaceutical companies have been responding in the same way to the Covid-19 pandemic as Roche, for example, continues both enrolment and dosing in the company’s Alzheimer’s late-stage trial of gantenerumab. On the other hand, Eli Lilly, which has several Alzheimer’s drugs in the pipeline—including solanezumab, in a Phase III trial for older individuals who may be at risk for memory loss—is halting enrollment and postponing new trials while continuing dosing in ongoing trials.
Axsome Therapeutics concluded patient participation early in the Phase III study of its lead drug candidate, AXS-05, in patients with Alzheimer’s agitation. The company already completed randomising hundreds of patients for both the AXS-05 and placebo arms, and more than 90% of patients enrolled had completed the five weeks of the study. The decision to accelerate the completion of this trial was made using the FDA’s Guidance on Conduct of Clinical Trials of Medical Products during Covid-19 Pandemic, which discusses the potential impact of the pandemic on the conduct of clinical trials and on the resulting need to ensure the safety of trial participants. With the acceleration of the trial, top-line results are expected in June 2020.
Conversely, Biogen was expected to complete FDA filing for its recombinant human monoclonal antibody (mAb) aducanumab in early 2020, but due to the coronavirus that affected several members of senior management, the regulatory filing and review is expected to take more time than originally estimated. Biogen also launched a new trial called EMBARK for people who were enrolled in Phase III trials of aducanumab at the Advanced Memory Centre. Due to Covid-19, the launch of the trial in other sites will not happen at least until June 2020.
With the current situation of lockdown in most of the countries, people ages65 and older are not able to participate in clinical trials. However, physicians are staying in contact with their participants and carers through remote technology. The research can still continue as researchers can collect and analyze some clinical and cognitive data. The disruption of important clinical research by the Covid-19 pandemic is linked also to the particular vulnerability of the older adults, the most targeted subjects by Covid-19. The number of deaths in the elderly population worldwide has already reached significant numbers, and participants of Alzheimer’s trials dying from coronavirus can significantly affect the outcome of Alzheimer’s studies.
To mitigate the disruption of Alzheimer’s clinical trials due to Covid-19, new interventions need to be implemented due to the inability to leave home. With the new technologies available, researchers and physicians can remotely screen potential participants rather than conducting in-person visits and support their families and carers during these difficult and uncertain times.