Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compounds of the Formula I: and tautomers and pharmaceutically acceptable salts and solvates thereof, wherein R1, R2 and R3 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.

Abstract: 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.

Abstract: Provided herein are compound of Formula I-IV and pharmaceutically acceptable salts thereof which exhibit rearranged during transfection (RET) kinase inhibition. In particular, provided herein are novel crystalline forms of 4-(6-(4-((6-methoxypyridin-3-yl)methyl)piperazin-1-yl)pyridin-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (Formula I), 6-(2-hydroxy-2-methylpropoxy)-4-(6-(6-((6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (Formula II), 6-(2-hydroxy-2-methylpropoxy)-4-(6-(6-(6-methoxynicotinoyl)-3,6-diazabicyclo[3.1.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.

Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compound of Formula I-IV and pharmaceutically acceptable salts thereof which exhibit rearranged during transfection (RET) kinase inhibition. In particular, provided herein are novel crystalline forms of 4-(6-(4-((6-methoxypyridin-3-yl)methyl)piperazin-1-yl)pyridin-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (Formula I), 6-(2-hydroxy-2-methylpropoxy)-4-(6-(6-((6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (Formula II), 6-(2-hydroxy-2-methylpropoxy)-4-(6-(6-(6-methoxynicotinoyl)-3,6-diazabicyclo[3.1.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.

Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.

Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.

Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.

Abstract: Provided herein are compounds of the Formula I: or pharmaceutically acceptable salt or solvate thereof, wherein A, B, X1, X2, X3, X4, Ring D, E, Ra, Rb, n and m 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.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.

Abstract: Provided herein are compounds of the Formula I: and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X1, X2, X3, X4, Ring D, and E 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.