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ALPINEImmuneSciences ™ NEWS RELEASE Alpine Immune Sciences Announces ALPN - 202 Clinical Data Presented at the 2021 ASCO Virtual Annual Meeting 6/4/2021 Alpine to hold an ALPN - 202 Investor Event on Friday , June 4 at 7:00 pm EDT SEATTLE -- ( BUSINESS WIRE ) -- Jun . 4 , 2021-- Alpine Immune Sciences , Inc. ( NASDAQ : ALPN ) , a leading clinical - stage immunotherapy company focused on developing innovative treatments for cancer and autoimmune / inflammatory diseases , announced presentation of initial data from NEON - 1 , the company's Phase 1 clinical trial of ALPN - 202 , a conditional CD28 costimulator and dual checkpoint inhibitor , at the American Society of Clinical Oncology ( ASCO ) Virtual Annual Meeting . NEON - 1 is a first - in - human , dose escalation and expansion study of ALPN - 202 monotherapy in advanced malignancies . Presentation highlights include : • ALPN - 202 has been generally well - tolerated as of the data cutoff date . The most common treatment - related adverse events have included immune - related toxicities , particularly cutaneous reactions . • Although most enrolled participants have had tumors considered classically non - responsive to immunotherapies , 61 % ( 14 of 23 evaluable ) appeared to derive clinical benefit as defined as a best outcome of stable disease or better , as of the data cutoff date . One of these participants , with metastatic colorectal cancer , achieved an unconfirmed partial response . • Dose - dependent pharmacokinetics and pharmacodynamics have been observed , accompanied by expansion of circulating CD4 + T cells with upregulation of the ICOS activation and Ki - 67 proliferation markers . An expansion of central memory T cells , and a downregulation of regulatory T cells , were also observed . 1