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ALECTOR Alector Reports 2021 First Quarter Financial Results and Provides Business Update May 5 , 2021 • Enrollment ongoing for AL001 INFRONT - 3 Phase 3 trial in frontotemporal dementia with a progranulin mutation and for AL002 INVOKE - 2 Phase 2 trial in early Alzheimer's disease patients • Three abstracts accepted for presentation at 2021 Alzheimer's Association International Conference ( AAIC ) , including updated data from ongoing AL001 open - label Phase 2 study in FTD - GRN SOUTH SAN FRANCISCO , Calif . , May 05 , 2021 ( GLOBE NEWSWIRE ) -- Alector , Inc. ( Nasdaq : ALEC ) , a clinical - stage biotechnology company pioneering immuno - neurology , today announced business updates and financial results for the first quarter ended March 31 , 2021 . " Positive momentum continues to build throughout our early and late - stage product pipeline , " said Arnon Rosenthal , Ph.D. , co - founder and chief executive officer of Alector . " Our pivotal AL001 INFRONT - 3 Phase 3 trial and AL002 INVOKE - 2 placebo - controlled Phase 2 trial continue to enroll patients , and we look forward to sharing additional data from the AL001 Phase 2 clinical development program in people with FTD - GRN this summer at AAIC . In parallel , we continue to prepare for the initiation of a Phase 2 study evaluating AL001 in people with amyotrophic lateral sclerosis and advance our early - stage novel immuno - oncology candidates toward first - in - human studies . This is an exciting time for Alector and we look forward to continued execution on our clinical and corporate objectives . " Key Business Updates Progranulin Portfolio : • Alector plans to present updated data from the ongoing AL001 Phase 2 open - label study at the upcoming Alzheimer's Association International Conference ( AAIC ) , taking place July 26-30 , 2021 . • Enrollment is ongoing in INFRONT - 3 , a randomized , placebo - controlled , pivotal Phase 3 trial evaluating AL001 in people at risk for or with frontotemporal dementia due to a progranulin gene mutation ( FTD - GRN ) . The ongoing pivotal trial is evaluating the efficacy and safety of AL001 in at - risk and symptomatic participants with FTD - GRN . Participants in the trial will be given the option to continue receiving treatment in an open - label extension study . • The Company is on track to initiate a Phase 2 study evaluating AL001 in people with amyotrophic lateral sclerosis ( ALS ) caused by C9orf72 repeats , which share TDP - 43 pathology with FTD - GRN in the second half of 2021 . Alzheimer's Disease Portfolio : • Alector continues patient enrollment in INVOKE - 2 , a Phase 2 trial evaluating AL002 in people with early Alzheimer's disease . The randomized , double - blind , placebo - controlled , dose - ranging , multi - center Phase 2 study is expected to enroll approximately 265 participants with early Alzheimer's disease ( AD ) at up to 90 sites globally . The AL002 clinical program is being developed in collaboration with AbbVie . • Alector plans to present two posters highlighting AL002 at AAIC , taking place July 26-30 , 2021. The first poster will include the results of the AL002 Phase 1 study in healthy volunteers and the second poster will highlight the study design of the ongoing INVOKE - 2 trial in people with early AD . • Data from the Phase 1b study evaluating AL003 in participants with AD is expected in 2021. Alector initiated the Phase 1b study in January 2020 and completed enrollment in 2020. The AL003 clinical development program is being developed in collaboration with AbbVie . Preliminary results from the study are expected to be presented at a scientific medical meeting in the second half of 2021 . Early - Stage Pipeline with Potential in Neurodegenerative Diseases and Oncology • The Company continues to progress AL044 , a first - in - class antibody targeting the MS4A4A receptor . MS4A4A is a major risk gene for AD that encodes a transmembrane receptor protein that is expressed selectively in microglia in the brain and is associated with control of microglia functionality and potential viability . • Planning is underway to initiate first - in - human studies for AL008 and AL009 , two oncology programs , in 2022 . AL008 is a novel , investigational , antibody product candidate with a dual mechanism of action that combines inhibition of the CD47 - SIRP - alpha ( SIRPa ) pathway with stimulation of activating Fc receptors and has the potential to yield a