Shares of Pinduoduo Inc. /zigman2/quotes/208876581/composite PDD +4.58% jumped 7.1% in premarket trading Tuesday, after the China-based mobile marketplace connecting agricultural producers and consumers reported a surprise second-quarter profit although revenue nearly doubled but missed forecasts. The company swung to net income of RMB2.41 billion ($373.97 million), or RMB1.69 per American depositary share, from a loss of RMB899.35 million, or RMB0.75 per ADS, in the year-ago period. Excluding nonrecurring items, adjusted earnings per share came to RMB2.85, beating the FactSet consensus for a per-share loss of RMB1.88. Revenue grew 89.0% to RMB23.05 billion ($3.57 billion), but missed the FactSet consensus of RMB26.63 billion. Average monthly active users rose 30% to 738.5 million, and active buyers in the 12-month period ended June 30 increased 24% to 849.9 million. The stock has tumbled 37.8% over the past three months through Monday, while the iShares MSCI China ETF /zigman2/quotes/206267952/composite MCHI +0.49% has dropped 15.1% and the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.97% has gained 6.7%.