After-Hours Movers Wednesday: Shake Shack Inc., JC Penney Co.

Shake Shack Inc. SHAK gained 7 percent to $73.16 in late trading Wednesday after the restaurant chain said first-quarter same-store sales increased 11.7 percent and total revenue grew 56.3 percent. Roundy's Inc. RNDY rose 3 percent to $4.73 in after-hours trading. The midwest grocer said first-quarter sales grew more than 13 percent and its net loss narrowed. Same-store sales fell 1.6 percent. Vipshop Holdings Ltd. VIPS gained 3 percent to $27.50 in the late session. The online discount retailer in China said first-quarter revenue doubled to $1.4 billion. Calithera Biosciences Inc. CALA picked up about 3 percent, trading at $13.40 in Wednesday's extended session. The company, which issued no news Wednesday, has seen its shares fall more than 30 percent during the most recent five trading days. J C Penney Company Inc. JCP rose 1.5 percent to $8.84. The retailer posted a narrower-than-expected loss and said first-quarter same-store sales grew 3.4 percent. Sphere 3D Corp. ANY fell 5 percent to $3.52 in late trading. The company announced a $4.1 million private placement after the bell at $3.20 for one common share and one warrant to purchase one common share. VOXX International Corp. VOXX declined 4 percent to $7.94 in after-hours trading Wednesday. The automotive and electronics accessories maker said fiscal fourth-quarter sales fell 9 percent although its loss narrowed. Camtek Ltd. CAMT dropped 7 percent in late trading to $3.15. The semiconductor equipment maker didn't issue news Wednesday. MasTec Inc. MTZ fell 4 percent to $16.24 in late trading. The company released first-quarter results Monday and said it had a "difficult start" to 2015. ONEOK Inc. OKE declined nearly 3 percent to $43.25. The company's shares closed up more than 2 percent earlier.