In the case of asymmetric information, if both parties sign a contract and one party goes back on his word, can the contract be terminated?

It is valid until it is revoked.

The rights and obligations of both parties are unequal and the economic interests are unbalanced, which violates the principle of fairness and reasonableness of the contract. This contract is revocable and has no legal effect from the date of revocation.

Legal basis:

Article 15 1 of the Civil Code

If one party takes advantage of the situation that the other party is in a critical state and lacks judgment ability, resulting in obviously unfair when a civil juristic act is established, the injured party has the right to request the people's court or an arbitration institution to cancel it.