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Halozyme Exhibit 99.1 HALOZYME REPORTS FIRST QUARTER 2021 RESULTS - First Quarter Revenue of $ 89.0 million , Up from $ 25.4 million in First Quarter of 2020 - Record Quarterly Royalties in the First Quarter of $ 36.9 million Representing 119 % Growth over First Quarter 2020- - Reiterate 2021 Revenue Guidance of $ 375 Million to $ 395 Million Representing 40 % to 48 % Growth over 2020 Revenue - - Reiterate 2021 GAAP Operating Income Guidance of $ 215 million to $ 235 million , Representing 49 % -63 % Growth over 2020 GAAP Operating Income - SAN DIEGO , May 10 , 2021 - Halozyme Therapeutics , Inc. ( NASDAQ : HALO ) today reported financial results for the first quarter ended March 31 , 2021 and provided an update on its recent corporate activities and outlook . " The first quarter marked a strong start to 2021 highlighted by record quarterly royalty revenue driven by the continued successful launch of subcutaneous DARZALEX® worldwide , " said Dr. Helen Torley , president and chief executive officer . " Our pipeline of partnered product candidates using ENHANZEⓇ technology continues to build momentum with four new clinical study starts in the first quarter . Additionally , we were able to strengthen our balance sheet on highly attractive terms reflective of the strong anticipated cash flow generation and growth prospects for Halozyme . " Recent Partner Highlights : • Janssen achieved several important successes related to the subcutaneous formulation of DARZALEX® ( daratumumab ) using ENHANZEⓇ technology during the first quarter and since including : ° о Janssen Pharmaceutical K.K. announced approval from Japan's Ministry of Health , Labour and Welfare ( MHLW ) in March for the subcutaneous formulation of DARZALEX® ( known as DALACUROⓇ in Japan ) for the treatment of multiple myeloma . Accordingly , Halozyme recognized $ 5 million in milestone revenues . The Janssen Pharmaceutical Companies of Johnson & Johnson announced Health Canada approved DARZALEX® SC ( daratumumab injection ) , a subcutaneous ( SC ) formulation of daratumumab , in combination with bortezomib , cyclophosphamide and dexamethasone ( D - VCd , also known as DCyBorD ) in April for the treatment of adult patients with newly diagnosed light chain ( AL ) amyloidosis . There were previously no approved therapies for the disease . Janssen Biotech , Inc. received U.S. Food and Drug Administration accelerated approval in January for DARZALEX FASPRO® ( daratumumab and hyaluronidase - fihj ) in combination with bortezomib , cyclophosphamide and dexamethasone ( D - VCd ) for the