GlobeNewswire Inc | Oct 9, 2020 10:15AM EDT

October 09, 2020

-- Results demonstrate a greater than 65% mean reduction in proteinuria at week 48 in C3G patients treated with pegcetacoplan -- Sustained improvements were seenacross key clinicalmeasures at 48 weeks -- There are no approved medicines for C3G, a rare disease that often leads to kidney failure

WALTHAM, Mass., Oct. 09, 2020 (GLOBE NEWSWIRE) -- Apellis Pharmaceuticals,Inc. (Nasdaq: APLS), a global biopharmaceutical company and leader in targeted C3 therapies, today announced that positive results from the Phase 2 DISCOVERY study evaluating pegcetacoplan, a targeted C3 therapy, in patients with C3 glomerulopathy (C3G) will be presented at the American Society of Nephrology (ASN) Kidney Week on October 22, 2020. The 48-week results show that patients treated with pegcetacoplan demonstrated sustained improvements across key clinical measures including a greater than 65% mean reduction in proteinuria, which is an important marker of renal damage. C3G is a rare, complement-driven kidney disease with no approved medicines.

In five C3G patients treated with pegcetacoplan, mean (SE) proteinuria decreased from 3.48 (0.82) mg/mg at baseline to 0.93 (0.27) mg/mg at week 48, a decrease of 73.3%, as measured by 24-hour urine protein-to-creatinine ratio (uPCR). Importantly, this reduction in proteinuria was accompanied by a corresponding increase in mean serum albumin. Other biomarkers improved, including an observed increase in mean serum C3 and stabilization of renal function, as measured by mean serum creatinine. No serious or severe adverse events were reported, and pegcetacoplan was well tolerated overall.

There is an urgent need for treatments for C3G, a disease that ultimately leads to kidney failure for about half of people living with the disease. These positive results highlight the potential of pegcetacoplan to make a meaningful difference for the C3G community and further strengthen our confidence in targeting C3 across multiple complement-driven diseases, said Federico Grossi, M.D., Ph.D., Chief Medical Officer of Apellis. We are working quickly to progress a registrational program of our targeted C3 therapy for people living with C3G.

Earlier this week, Apellis announced that it was advancing Phase 2 and Phase 3 studies of pegcetacoplan in patients with C3G or immune complex membranoproliferative glomerulonephritis (IC-MPGN), another rare, complement-driven kidney disease with no approved medicines.

Presentation Details at ASN Kidney Week 2020

C3 Inhibition with Pegcetacoplan Targets the Underlying Disease Process of C3 Glomerulopathy (C3G) and Improves Proteinuria, ePoster # PO1852 Oct. 22at 10:00 a.m. ET.

About the DISCOVERY StudyThe DISCOVERY study is a Phase 2, open-label trial designed to evaluate the preliminary efficacy and safety of pegcetacoplan in patients with complement-driven renal diseases. Eight C3G patients were enrolled into the study. Three patients were excluded from the analysis at 48 weeks due to self-reported non-compliance or study drug interruption.

The primary endpoint in the DISCOVERY study is change from baseline in proteinuria at week 48 as measured by 24-hour urine protein-to-creatinine ratios (uPCR). Secondary endpoints include analysis of serum C3 and estimated glomerular filtration rate (eGFR).

About Pegcetacoplan (APL-2)Pegcetacoplanis an investigational, targeted C3 therapy designed to regulate excessive complement activation, which can lead to the onset and progression of many serious diseases.Pegcetacoplanis a synthetic cyclic peptide conjugated to a polyethylene glycol polymer that binds specifically to C3 and C3b.Apellis is evaluatingpegcetacoplanin several clinical studies across hematology, ophthalmology, nephrology, and neurology.Pegcetacoplanwas granted Fast Track designation by the U.S. Food and Drug Administration (FDA) forthe treatment of paroxysmal nocturnal hemoglobinuria (PNH) and the treatment of geographic atrophy, and received orphan drug designation for the treatment of C3G by the FDA and European Medicines Agency. For additional information regarding our clinical trials,visit https://apellis.com/our-science/clinical-trials.

About C3 Glomerulopathy (C3G) and Immune Complex Membranoproliferative Glomerulonephritis (IC-MPGN)C3G and IC-MPGN are rare, debilitating kidney diseases that affect ~18,000 people in the United States and Europe.1 There are no approved therapies for the diseases, and symptoms include blood in the urine, dark foamy urine due to the presence of protein, swelling and high blood pressure.2 Approximately 50% of people living with C3G and IC-MPGN ultimately suffer kidney failure within five to 10 years of diagnosis.3 Although IC-MPGN is considered a distinct disease from C3G, the underlying cause and progression of the two diseases are remarkably similar and include overactivation of the complement cascade, with excessive accumulation of C3 breakdown products in the kidney causing inflammation and damage to the organ.4,5

About ApellisApellis Pharmaceuticals, Inc. is a global biopharmaceutical company that is committed to leveraging courageous science, creativity, and compassion to deliver life-changing therapies. Leaders in targeted C3 therapies, we aim to develop best-in-class and first-in-class therapies for a broad range of debilitating diseases that are driven by uncontrolled or excessive activation of the complement cascade, including those within hematology, ophthalmology, nephrology, and neurology. For more information, pleasevisit http://apellis.com.

Apellis Forward-Looking StatementStatements in this press release about future expectations, plans and prospects, as well as any other statements regarding matters that are not historical facts, may constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to, statements relating to the implications of preliminary clinical data. The words anticipate, believe, continue, could, estimate, expect, intend, may, plan, potential, predict, project, should, target, will, would and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: whether the companys clinical trials will be fully enrolled and completed when anticipated; whether preliminary or interim results from a clinical trial will be predictive of the final results of the trial; whether results obtained in preclinical studies and clinical trials will be indicative of results that will be generated in future clinical trials; whetherpegcetacoplanwill successfully advance through the clinical trial process on a timely basis, or at all; whether the results of the companys clinical trials will warrant regulatory submissions and whetherpegcetacoplanwill receive approval from the FDA or equivalent foreign regulatory agencies for GA, PNH, CAD, C3G, IC-MPGN, ALS or any other indication when expected or at all; whether, if Apellis products receive approval, they will be successfully distributed and marketed; and other factors discussed in the Risk Factors section of Apellis Quarterly Report on Form 10-Q filed with theSecurities and Exchange Commissionon July 30, 2020and the risks described in other filings that Apellis may make with theSecurities and Exchange Commission. Any forward-looking statements contained in this press release speak only as of the date hereof, and Apellis specifically disclaims any obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise.

Contacts:MediaTracy Vineismedia@apellis.com+1617420 4839

InvestorsSam Martin / Maghan Meyerssam@argotpartners.com / maghan@argotpartners.com +1212600 1902

1 ClearView Analysis using physician and literature consensus.2 Complement 3 Glomerulopathy (C3G). National Kidney Foundation Web site. https://www.kidney.org/atoz/content/complement-3-glomerulopathy-c3g. Accessed November 21, 2019.3 C3 glomerulopathy. National Institute of Health, Genetics Home Reference. https://ghr.nlm.nih.gov/condition/c3-glomerulopathy#resources. Accessed November 21, 2019.4 Noris M, Donadelli R, Remuzzi G. Autoimmune abnormalities of the alternative complement pathway in membranoproliferative glomerulonephritis and C3 glomerulopathy. Pediatr Nephrol. 2019 Aug;34(8):1311-1323.5 Cook HT. Evolving complexity of complement-related diseases: C3 glomerulopathy and atypical haemolytic uremic syndrome. Curr Opin Nephrol Hypertens. 2018 May;27(3):165-170.