Shares of Peloton Interactive Inc. PTON, +8.23% rallied 2.7% in premarket trading Wednesday, after the at-home fitness company announced an expanded collaboration with Amazon.com Inc. AMZN, +0.46% in the U.K. and Germany. The company said the Peloton Bike, Guide and certain accessories are now available in Amazon's U.K. store for in-home delivery, and will be available in Amazon's German store in the coming weeks.