May 8 (Reuters) - Tripadvisor shares slumped 38% and were on track for their worst day ever on Wednesday, after the online travel agency ruled out a possible sale at this time and posted a surprise quarterly loss.

Tripadvisor first disclosed in February that Liberty TripAdvisor Holdings, its controlling shareholder, had been approached by at least one bidder for its controlling stake in the travel agency.

A special committee formed to explore options, including a potential sale, has determined there is no transaction with a third party that is in the best interests of the company at this time, Tripadvisor said on Wednesday.

"The special committee will continue to evaluate proposed alternatives as appropriate. There can be no assurance that any transaction will result," CEO Matthew Goldberg said on a post-earnings call with analysts on Wednesday.

Tripadvisor reported a first-quarter loss of 43 cents per share on Wednesday, while analysts on average expected a profit of 2 cents, according to LSEG data.

Liberty TripAdvisor is one of media mogul John Malone's publicly traded vehicles. It holds a 56% stake in Tripadvisor and is controlled by Liberty Media CEO Greg Maffei, who is also Tripadvisor's chairman. (Reporting by Kannaki Deka in Bengaluru; Editing by Shilpi Majumdar)