Several years ago, anti-Alzheimer’s agents called Solanezumab (Eli Lilly) and Bapineuzumab (Janssen and Pfizer) already failed due to a lack of clinical efficacy signals. In 2022, Crenezumab and Gantenerumab, two candidates from Swiss pharmaceutical company Roche, also failed to show effectiveness against the fatal brain disease and thus also dropped out of the clinical approval process.
Even the most promising drug candidate to date, Aducanumab (Biogen/Eisai), which made it to approval in 2021, albeit in a highly controversial approval process and only in the U.S., has questionable efficacy. In Europe, its approval was rejected by the European Medicines Agency (EMA) due to “an unproven efficacy and possible serious side effects of the drug.” Approved in the U.S., aducanumab is the first new Alzheimer’s drug since 2003, and its slowing effect on cognitive decline has been reported at 22%, but with life-threatening side effects such as brain swelling and hemorrhage in more than 30% of study participants, and also extremely high therapy costs. The patient benefit is therefore questionable. Read more about the approval fiasco concerning Aducanumab here.
Currently, two monoclonal antibodies against Aβ are in the late phase of clinical development: Donanemab of the pharmaceutical company Eli Lilly (Trailblazer-ALZ2 study) and Lecanemab of the companies Eisai and Biogen (Clarity-AD study). Both are IgG1 monoclonal antibodies that target insoluble, or clumped, forms of Aβ.
Recently, the results of the Clarity-AD study with Lecanemab were published in a press release from the manufacturer Biogen: Lecanemab slowed mental decline by 27% in patients, and a rapid marketing approval is being targeted by the manufacturers Biogen and Eisai. To read about how this study should be evaluated, please click here.
The result of the Trailblazer-ALZ2 study with Donanemab is expected in 2025.