Abemaciclib extends survival in metastatic breast cancer

Treatment with abemaciclib, either alone or in combination with fulvestrant, results in improved overall (OS) and progression-free survival (PFS) in patients with HR+/HER2– advanced or metastatic breast cancer, as shown in a recent study.

Investigators conducted a systematic review and meta-analysis using the PRISMA guidelines. They searched the databases of PubMed, Embase, Cochrane Library, and ClinicalTrials.gov through December 2023 and identified randomized controlled trials and retrospective cohort studies that reported on abemaciclib in approved doses, either as monotherapy or combination therapy.

PFS, OS, overall response rate (ORR), and side effects/adverse effects (SE/AE) were assessed. Study quality was evaluated using Cochrane’s revised risk of bias tool and the Newcastle-Ottawa scale.

Twenty-two studies, involving a total of 14,010 patients, met the inclusion criteria. Pooled results revealed significant improvements with abemaciclib in PFS (hazard ratio, 0.53, 95 percent confidence interval [CI], 0.48–0.59; p=0.00; I², 0 percent), ORR (risk ratio [RR], 2.31, 95 percent CI, 1.93–2.75; p=0.00; I², 0 percent), and OS (RR, 0.76, 95 percent CI, 0.65–0.87; p=0.001; I², 0 percent).

On the other hand, the use of abemaciclib elevated the risk of AEs in the fulvestrant and nonsteroidal aromatase inhibitor combinations.

“The higher toxicity profile warrants cautious use, especially in treatment-naive patients,” the investigators said. 

Abemaciclib is a CDK4/6 inhibitor that has shown promising results in treating advanced cases.