Keep crème fraîche refrigerated. Once your order arrives, remove it from the shipping package promptly and place it in the coldest appropriate section of your refrigerator. Caviar Express packages perishable products with Gel-Ice to help maintain freshness during transit.
The current Caviar Express source does not provide a product-specific opened shelf life for this crème fraîche, so I would not add one to the PDP unless Caviar Express confirms it.