Vaxcyte's (PCVX) results for vaccine candidate VAX-24 came in below some Wall Street expectations but were still fundamentally positive, Mizuho Securities said in a research note Monday.

The clinical-stage company released this morning post-dose 3 and interim post-dose 4 data from a mid-stage trial of VAX-24, which was designed to prevent invasive pneumococcal disease in children.

The same four serotypes missed the post-dose 3 greater than or equal to 15% lower bound confidence interval of the difference of seroconversion rates across all doses, Mizuho said, adding that a fifth serotype missed when considering the more conservative greater than or equal to 10% lower bound confidence interval.

"While the Street was looking for [less than or equal to] 3 serotype misses (thus slightly missing this bogey, albeit somewhat arbitrary), the data still would likely represent the broadest [pneumococcal conjugate vaccine] in infants (and would seem approvable/marketable)," the note said.

Vaxcyte shares were down 53% in recent trading.

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