Provided herein are compounds of the Formula I: [INSERT FORMULA I] and tautomers, stereoisomers and pharmaceutically acceptable salts and solvates thereof, wherein R1, R2 and Ry have the meanings given in the specification, which are inhibitors of RET kinase and are useful in the treatment and prevention of diseases which can be treated with a RET kinase inhibitor, including RET-associated diseases and disorders.