The US Food and Drug Administration (FDA) is currently reviewing a petition to revoke the approval of Roche's ocrelizumab (Ocrevus) for treating primary progressive multiple sclerosis (PPMS), a condition affecting approximately 15% of MS patients. The petition, initiated by patient advocate Kaylin Bower, alleges that the drug was approved despite internal FDA concerns regarding its effectiveness in women and a potential increased risk of breast cancer. An investigation published by The BMJ highlights that several FDA scientists had recommended against the drug's approval, citing findings of 'near zero efficacy' for certain patients and an 'unusual imbalance' in breast cancer cases. Despite these warnings, the drug was approved in 2017 by Billy Dunn, the FDA's top neuroscience official at that time, who did not consult the external advisory committee. Critics argue that the approval process for Ocrevus, along with other drugs like aducanumab and lecanemab, raises questions about the FDA's approach to drugs intended for unmet medical needs. Roche maintains that it monitors malignancy cases closely and claims that its data does not indicate new safety concerns, although it has not released interim breast cancer data due to a publication embargo. The ongoing safety study on breast cancer risk is not scheduled to report until late 2030, leaving many questions unanswered regarding the long-term implications of Ocrevus's use in women.