Risk evaluation and mitigation strategy (REMS) programs help ensure that the benefits of certain high-risk medications outweigh their risks. With the routine use of REMS programs, however, concerns have emerged that they may delay the approval of generic alternatives. Using a data set of novel small-molecule drugs approved during the period 2000-13, linked to generic approvals through 2024, we assessed the impact of REMS programs on generic approval. We found that the existence of a REMS program was associated with a 25 percent delay in generic approvals after patent length, approval timing, approved indication, boxed warning status, orphan drug status, and drug use were controlled for. Our findings provide insight into future regulatory efforts that can facilitate timely access to safe, effective, and affordable generic drugs.