Eli Lilly has recently proved that donanemab, an investigational treatment for Alzheimer’s disease, slowed the disease progress in a phase-2 study.
Industry officials are paying attention to whether the latest study results will affect aducanumab's approval, another experimental Alzheimer’s drug developed by rival company Biogen.
On Monday, Lilly announced that donanemab, an antibody targeting a modified form of beta-amyloid called N3pG, met the primary endpoint of the phase-2 TRAILBLAZER-ALZ study.
Donanemab-treated patients showed a 32 percent decline in change from baseline to 76 weeks in the Integrated Alzheimer's Disease Rating Scale (iADRS), according to Lilly. The iADRS is a clinical composite indicator combining two commonly used measures in Alzheimer's disease -- the cognitive measure ADAS-Cog13 and functional measure ADCS-iADL.
Also, Lilly’s experimental treatment showed consistent improvements in all pre-specified secondary endpoints compared to placebo.
However, donanemab did not reach nominal statistical significance on every secondary endpoint, the company said.
The amyloid scan showed that donanemab produced high levels of amyloid plaque clearance. Donanemab-treated patients showed an 84 centiloid reduction of amyloid plaque on average at 76 weeks, compared to a baseline of 108 centiloids. Less than 25 centiloid is regarded as negative in an amyloid scan.
In the study, patients stopped receiving donanemab and switched to placebo if their plaque level was below 25 centiloids for two consecutive measures or blew 11 centiloids at any one measure.
“This unique mechanism and antibody for clearing plaques, discovered at Lilly, has the potential to provide high levels of durable amyloid plaque clearance after limited duration dosing,” said Daniel Skovronsky, Lilly's chief scientific officer and president of Lilly Research Laboratories.
“The positive results we have obtained today give us confidence in donanemab and support its rapid and deep plaque clearance for the potential treatment of Alzheimer's disease."
Lilly said it would present the TRAILBLAZER-ALZ study's full results at a future medical congress and publish them in a clinical journal.
The company will also continue the TRAILBLAZER-EXT trial for the participants of the TRAILBLAZER-ALZ study.
Lilly said it planned to discuss the latest results with regulators to assess the next steps for donanemab, drawing attention to whether its move would affect regulators’ decision to grant the nod for Biogen’s aducanumab.
Biogen is waiting for the U.S. FDA to decide by March whether to approve aducanumab as the first treatment for Alzheimer’s disease. In November, the FDA’s advisory committee recommended not to grant the nod, saying aducanumab did not have sufficient data to prove its efficacy. However, the FDA does not have to follow the panelists’ recommendations.
Participating in JP Morgan Healthcare Conference on Monday, Biogen still picked aducanumab as the most promising portfolio. The company is preparing to release aducanumab in the U.S. and has submitted approval applications to regulators in Europe and Japan.
However, investors are preparing to file a class-action lawsuit against Biogen in the U.S. Class actions law firms encourage shareholders who purchased Biogen securities between Oct. 22, 2019, and Nov. 6, 2020, to join the case.
On Oct. 22, 2019, Biogen officially announced the effectiveness of aducanumab, and on Nov. 6, 2020, the FDA’s advisory committee disclosed the votes' results.
Law firms claim that Biogen made false or misleading statements during the period. They also said that investors suffered damages because the company did not disclose facts unfavorable to the company.