Does PB2 need to be refrigerated?

Excuse me, I was reading the instructions for the PB2 product and I noticed it didn't explicitly state whether or not it needs to be refrigerated after opening. Could you please clarify for me if PB2 should be stored in the refrigerator or if it's SAFE to keep it at room temperature? I'd like to ensure that I'm handling it properly to maintain its freshness and quality. Thank you for your assistance.