Why Is Vaxcyte ($PCVX) Stock Up +37.38% Today? (Find out why any stock moved today on Tickeron.) PCVX shares surged roughly 37% in Monday's session after the company reported positive topline results from its pivotal Phase 3 trial of the VAX-31 pneumococcal vaccine candidate. The primary catalyst was clinical data: VAX-31 met all co-primary immunogenicity endpoints in adults aged 50 and older in the OPUS-1 trial. Secondary drivers included a wave of bullish analyst commentary, with several firms raising price targets and reaffirming Buy ratings. The move reflects renewed confidence in the company's franchise within a large and growing pneumococcal conjugate vaccine (PCV) market. Traders are now watching for the regulatory path forward, upcoming additional Phase 3 readouts, and how shares consolidate after the gap higher. $BCYC $SRRK $DNLI $VIR $MIRM