The FDA's Drugs@FDA database lists a supplement dated 18 September 2026 to NDA208716, Eli Lilly's abemaciclib (Verzenio), the CDK4/6 inhibitor used in hormone receptor-positive, HER2-negative breast cancer. The record gives no detail on what the supplement changes. The preceding three weeks also saw supplements recorded for everolimus (Zortress), toripalimab (Loqtorzi) and abrocitinib (Cibinqo), likewise without detail.
Supplements cover everything from manufacturing and labelling updates to new indications, so nothing about prescribing can be inferred until the revised label is published. For abemaciclib, the clinical-pharmacology points are unchanged: it is a CYP3A4 substrate, strong CYP3A inhibitors require dose reduction and strong inducers should be avoided, and diarrhoea and neutropenia are the common dose-limiting toxicities.
- No change in abemaciclib prescribing follows from this record alone.
- Check for strong CYP3A4 inhibitors (clarithromycin, itraconazole, ritonavir) and reduce the dose if they cannot be avoided.
- Avoid strong CYP3A4 inducers such as rifampicin, carbamazepine and phenytoin.
- Start antidiarrhoeal therapy at the first loose stool and monitor blood counts.
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