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SELLAS LIFE SCIENCES GROUP NEWS RELEASE SELLAS Life Sciences Reports First Quarter 2021 Financial Results and Provides Business Update 5/13/2021 Received $ 1.0 Million Milestone Payment and Recognized $ 5.7 Million of License Revenue Under Exclusive License Agreement with 3D Medicines for Development and Commercialization of Galinpepimut - S ( GPS ) in Greater China National Ethics Committee Approval for GPS Phase 3 REGAL Study Received in Greece Preparations Underway to Activate Clinical Trial Sites and Enroll Patients in the REGAL Study in France , Germany and Greece by End of Second Quarter 2021 NEW YORK , May 13 , 2021 ( GLOBE NEWSWIRE ) -- SELLAS Life Sciences Group , Inc. ( Nasdaq : SLS ) ( " SELLAS " or the " Company " ) , a late - stage clinical biopharmaceutical company focused on developing novel cancer immunotherapies for a broad range of indications , today reported its financial results for the quarter ended March 31 , 2021 and provided a business update . " Under our exclusive license agreement with 3D Medicines for the development and commercialization of galinpepimut - S ( GPS ) in Greater China , we advanced the technology transfer to 3D Medicines during the first quarter of 2021. In February , our progress triggered a milestone payment of $ 1.0 million . This achieved milestone is the first of milestone payments that have the potential to total $ 194.5 million over the life of the agreement . In addition to the $ 1.0 million payment , we further strengthened our balance sheet during the first quarter with approximately $ 3.0 million in net proceeds from warrant exercises , " said Angelos Stergiou , MD , SCD . h.c. , President and Chief Executive Officer of SELLAS . " During the quarter , we continued to progress our GPS clinical program with the activation of additional clinical sites in the United States , and also preparations for opening clinical sites and enrolling patients in European countries , for our Phase 3 REGAL study of GPS in patients with acute myeloid leukemia ( AML ) . Screening and enrollment of patients for the REGAL study is ongoing in the United States . " 1