Use a CTE. This is roughly what it should look like.

with cteParams as 
(select explode(split(?, ',')) as MyParamValue)
SELECT DISTINCT
       dimpractice.PracticeId,
       dimpractice.PracticeName AS Practice
FROM curated.dimprojectmaster
    INNER JOIN curated.dimorganization
        ON dimprojectmaster.OrganizationID = dimorganization.OrganizationID
    INNER JOIN curated.dimpractice
        ON dimorganization.PracticeID = dimpractice.PracticeID
    INNER JOIN curated.dimprofitcenter
        ON dimorganization.ProfitCenterID = dimprofitcenter.ProfitCenterID
    INNER JOIN curated.dimoffice
        ON dimprofitcenter.OfficeID = dimoffice.OfficeID
      AND dimprojectmaster.ChargeType IN ('Regular', 'Promotional')
    inner join cteParams on dimoffice.OfficeName = cteParams.MyParamValue
ORDER BY Practice