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VAXCYTE protect humankind ™ Vaxcyte Reports Second Quarter 2026 Financial Results and Provides Business Update Exhibit 99.1 Topline Safety , Tolerability and Immunogenicity Data from VAX - 31 Adult Phase 3 OPUS - 1 Trial Expected in Fourth Quarter of 2026 ; OPUS - 2 and OPUS - 3 Phase 3 Results Expected in First Half of 2027 Topline Safety , Tolerability and Immunogenicity Data from Primary Immunization Series and Booster Dose of VAX - 31 Infant Phase 2 Dose - Finding Study Expected Either Sequentially or Together by End of First Half of 2027 Company Initiated Phase 1 Study Evaluating VAX - A1 for the Prevention of Disease Caused by Group A Streptococcus in Healthy Adults ; Topline Data Expected in Second Half of 2027 Approximately $ 2.5 Billion in Cash , Cash Equivalents and Investments as of June 30 , 2026 SAN CARLOS , Calif . , August 5 , 2026 - Va cyte , Inc. ( Nasdaq PCVX ) , a clinical - stage vaccine innovation company , today announced financial results for the second quarter ended June 30 , 202 , and provided a business update . " With the VAX - 31 OPUS - 1 , OPUS - 2 and OPUS - 3 Phase 3 trials and the VAX - 31 Phase 2 infant study fully enrolled , we e pect a series of meaningful clinical study readouts across our adult and infant pneumococcal conjugate vaccines ( PCV ) franchise over the ne t 12 months , " said Grant Pickering , Chief E ecutive Officer and Co - Founder of Va cyte . " We are on track to deliver the topline data from the OPUS - 1 noninferiority trial in the fourth quarter of this year . Following , we e pect to announce the results of the OPUS - 2 and OPUS - 3 trials in the first half of 2027 , which along with a manufacturing consistency study , would enable our planned Biologics License Application ( BLA ) submission and potential U.S. commercial launch . " " With $ 2.5 billion in cash , cash equivalents and investments as of June 30 , 202 , we maintain a strong balance sheet and are well positioned to e ecute on our planned clinical , manufacturing and commercial - readiness milestones across our PCV development programs , " said Andrew Guggenhime , President and Chief Financial Officer of Va cyte . " As we prepare for the Company's ne t phase of growth , we continue to advance our early- stage pipeline , including VAX - A1 , a prophylactic vaccine candidate designed to prevent disease caused by Group A Strep , now in a Phase 1 adult study , and VAX - XL , our preclinical , ne t - generation PCV candidate designed to provide the broadest coverage of any PCV currently in development . " Key Second Quarter and Recent Highlights PCV Franchise Adult Indication :