There are disclosed novel 5,7-disubstituted [1,3]thiazolo[4,5-d]pyrimidin-2(3H)-one derivatives of formula (I) wherein R1, R2, R3, R4 and n are as defined in the specification, and pharmaceutically acceptable salts thereof, together with processes for their preparation, pharmaceutical compositions comprising them and their use in therapy. The compounds of formula (I) are CX3CR1 receptor antagonists and are thereby particularly useful in the treatment or prophylaxis of neurodegenerative disorders, demyelinating disease, cardio- and cerebrovascular atherosclerotic disorders, peripheral artery disease, rheumatoid arthritis, pulmonary diseases such as COPD, asthma or pain.