Ann Intern Med

Delaying pegfilgrastim to 72 hours cuts bone pain without loss of protection

March 25, 2026

In a prospective, randomized phase 3 trial (NCT05841186) of 159 chemotherapy‑naive patients with stage I–III breast cancer, pegfilgrastim given 72 hours after chemotherapy was associated with substantially lower bone pain during the first cycle compared with 24‑ or 48‑hour dosing. Overall bone pain severity over 5 days was lower (6.05 vs. 12.74 and 14.20), and severe bone pain occurred less often (22.6% vs. ~60%). Rates of neutropenia didn't differ among groups, and no febrile neutropenia occurred.

Clinical takeaway: When feasible, consider administering pegfilgrastim 72 hours post‑chemotherapy to reduce bone pain without apparent compromise in neutropenia prevention.

Source:

Li P, et al. (2026, March 24). Ann Intern Med. Timing of Pegfilgrastim Administration and Pegfilgrastim-Induced Bone Pain : A Prospective, Randomized, Phase 3 Trial. https://pubmed.ncbi.nlm.nih.gov/41871353/