How do I get base type of a generic class

[calidan-x]

let say I have generic class

class Request<T, K, L> { field1: T field2: K obj: L }

I know I can get <T, K, L> by calling getTypeArguments()

Is there a method to get the class Request without generic args?

For this type I call .isClass() and it returns false. Is there another method to check it's a class?