Express Scripts Holding Co. shares slipped in the extended session Wednesday after the pharmacy-benefits manager's quarterly revenue and outlook fell below Wall Street estimates. Express Scripts shares declined 1.3% after hours, following a 2.4% decline to close at $74.05 in the regular session. The company reported first-quarter net income of $623.2 million, or $1.10 a share, compared with $546.3 million, or 90 cents a share, in the year-ago period. Adjusted earnings were $1.77 a share. Revenue rose to $24.77 billion from $24.65 billion in the year-ago period. Analysts surveyed by FactSet had estimated $1.76 a share on revenue of $24.81 billion. For the year, Express Scripts estimates earnings of $9 to $9.14 a share, down from a previously estimated range of $9.27 to $9.47 a share, because it suspended its share buyback program owing to its pending merger with Cigna Corp. Analysts had forecast earnings of $9.30 a share.