Drug delivery devices having a drug-permeable component and methods of making and using the same are provided. Drug delivery devices include a housing having a first and second wall structures that are adjacent one another and together form a tube defining a drug reservoir lumen. The second wall structure, or both the first wall structure and the second wall structure, are permeable to water, and the first wall structure is impermeable to the drug while the second wall structure is permeable to the drug, such that the drug is releasable in vivo by diffusion through the second wall structure.