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ANNEXON biosciences Annexon Biosciences Reports Second Quarter 2021 Financial Results and Provides Mid - Year Business Update August 16 , 2021 - Recently expanded Autoimmune franchise with advancement of third clinical candidate , ANX009 , and strategically expanded into additional autoantibody - driven diseases - - Continued progress in Neurodegeneration franchise with initial Phase 2 data results from ANX005 in Huntington's disease expected in Q4 2021 and initiation of Phase 2 ANX005 trial in Amyotrophic Lateral Sclerosis – - Appointed William D. Waddill to the Board of Directors - -- SOUTH SAN FRANCISCO , Calif . , Aug. 16 , 2021 ( GLOBE NEWSWIRE ) Annexon , Inc. ( " Annexon " ) ( Nasdaq : ANNX ) , Annexon , a clinical - stage biopharmaceutical company developing a class of new complement medicines for patients with classical complement - mediated autoimmune and neurodegenerative disorders of the body , brain and eye , today announced second quarter 2021 financial results and provided a mid - year business update . " We continue to make strong and consistent progress on our mission to deliver transformative therapies for patients suffering from classical complement - driven autoimmune and neurodegenerative diseases . With three clinical - stage drug candidates advancing in seven clinical trials , we remain laser - focused on developing game - changing therapies for patients in need while generating significant value for our shareholders , " said Douglas Love , Esq . , president and chief executive officer of Annexon . " We also continue to expand our corporate capabilities and are pleased to announce the appointment of Will Waddill to our Board of Directors . Will has extensive experience in biotech and finance , and will provide an invaluable perspective as we enter our next phase of growth and value creation . " Therapeutic Franchise Highlights and Updates Annexon is advancing a portfolio of innovative C1 inhibitors to stop classical complement - mediated diseases at the start of the pathway in three therapeutic franchise areas : Autoimmune , Neurodegeneration and Ophthalmology . Autoimmune Franchise Annexon is pursuing a range of carefully selected neuromuscular , hematologic and nephritic antibody - mediated autoimmune indications where excess classical complement activity is a key driver of disease . During its July 28th C1q R & D series presentation , Annexon showcased the rationale and potential of its anti - C1 approach in autoimmune disease . Recent highlights and updates in the Autoimmune franchise include : • Progressed enrollment in the Phase 2/3 trial of ANX005 in Guillain - Barré Syndrome ( GBS ) , which remains on track for completion in 2023. Data from the completed drug - drug interaction study and Phase 1b trial were recently presented at the 2021 Peripheral Nerve Society Annual Meeting , demonstrating tolerability and full C1q target engagement of ANX005 in combination with IVIg and reduction of cerebrospinal fluid ( CSF ) complement activity following ANX005 treatment in GBS patients . • Advanced precision medicine approach to treat patients with a complement signature in the Phase 2 trial of ANX005 in warm autoimmune hemolytic anemia ( wAIHA ) . In the ongoing Phase 0 ( patient selection ) component of the trial , several wAIHA patients have demonstrated a classical complement signature , making them potentially eligible for enrollment into the Phase 2 component of the trial . ANX005 was shown to fully inhibit complement activation of WAIHA antibodies in these patient sera . Data from the Phase 0 portion of the Phase 2 trial is expected to be submitted to a peer - reviewed forum in 2021 . • Strategic expansion of ANX005 into a Phase 2 program in Multifocal Motor Neuropathy ( MMN ) , a neuromuscular disorder mechanistically related to GBS . Initiation of the Phase 2 study is anticipated in early 2022 . • Reported Phase 1 first - in - human ( FIH ) data for ANX009 subcutaneous product candidate , Annexon's third clinical stage drug candidate , which is being developed for the treatment of antibody - mediated autoimmune diseases of blood and vascular tissues . ANX009 was shown to be well tolerated with complete and sustained C1q inhibition , supporting twice weekly subcutaneous administration . Data from the FIH study is expected to be submitted to a peer - reviewed forum in 2021 . • Advanced ANX009 into a Phase 1b study in Lupus Nephritis ( LN ) , a nephritic disease characterized by autoantibody - driven activation of C1q and the classical complement pathway . Endogenous pathogenic anti - C1q antibodies ( PACAs ) have been shown to correlate with classical complement activation and disease activity . Initiation of the Phase 1b study is anticipated in early 2022 and will deploy Annexon's precision medicine approach targeting patients with excess classical complement and PACA activity . Complement and PACA data in LN patient samples is expected to be