The invention provides azaspiro[4.5]decane derivatives of Formula (A): and pharmaceutically acceptable salts, solvates, hydrates, N-oxides, and diastereomers thereof, wherein A1, X, A2, Rr, R2&prime；, W1, R3&prime；, R4&prime；, a, and b are defined in the disclosure. The invention also provides compounds of Formulae I, and B-G, and pharmaceutically acceptable salts, solvates, hydrates, N-oxides, and diastereomers thereof. Further, the invention provides use of the compounds of Formulae A-G and I, and the pharmaceutically acceptable salts, solvates, hydrates, N-oxides, and diastereomers thereof, to treat pain. In certain embodiments, Compounds of the Disclosure are useful for treating a disorder responsive to blockade of one or more sodium channels.
