Abstract OT1-05-01: The incidence of febrile neutropenia (FN) for chemotherapy patients receiving pegfilgrastim by an on-body injector (pegfilgrastim OBI) versus other FN prophylaxis strategies
Authors: Mahtani Reshma , Crawford Jeffrey , Rifkin Robert , Dale David , Brookhart Alan , Gawade Prasad , Lawrence Tatiana , Balani Rejesh , Lyman Gary H 
Published: March 2020

For safety reasons, pegfilgrastim should be administered the day after chemotherapy for prophylaxis of chemotherapy-induced FN (Lyman et al, Cancer. 2017;25:2619-2629). Because this is inconvenient, the pegfilgrastim OBI was developed to reliably deliver pegfilgrastim at 27 hours after its application. There are limited real-world data on whether this strategy improves patient persistence, compliance, and outcomes, and there are no published real-world data on FN risk among high-risk patients receiving other approaches to FN prophylaxis. For this reason, we are conducting a multicenter, prospective, observational cohort study at ~150 sites in the US to determine the risk of FN over the first 4 cycles of myelosuppressive chemotherapy among patients receiving pegfilgrastim OBI or alternative choices for FN prophylaxis.

Eligible patients are stratified into 2 groups, curative or palliative intent, and classified into subgroups of FN prophylaxis based on the first chemotherapy cycle: receiving pegfilgrastim OBI vs other physician choice (ie, pegfilgrastim prefilled syringe [PFS], pegfilgrastim biosimilar PFS, daily filgrastim, or no G-CSF). Patients will be followed from screening/enrollment through completion of the 4th cycle of chemotherapy. Patients receiving pegfilgrastim OBI with every chemotherapy cycle (≤ 4 cycles) are defined as “on-label pegfilgrastim OBI”, a subset of the pegfilgrastim OBI subgroup. Two interim analyses will be conducted after 1,000 and 2,000 patients have been enrolled and received study treatment; a steering committee will review the results.

Eligible patients are ≥ 18 years old with non-Hodgkin lymphoma or breast, lung, or prostate cancer who are starting or have recently started (within 7 days) myelosuppressive chemotherapy in the neoadjuvant/adjuvant or first-line advanced/metastatic setting. Chemotherapy must be high (&gt; 20%) or intermediate (10–20%) FN risk and administered once every 3 or 4 weeks with ≥ 4 cycles planned. Patients receiving intermediate risk regimens must also have ≥1 risk factor for FN.

The primary endpoint is the overall incidence of FN (ANC &lt; 1000 x 106/L and temperature &gt;38°C, use of specific oral antibiotics, or use of IV antibiotics within 24 h of decreased ANC) over 4 cycles. Additional endpoints include incidence of FN among patients receiving chemotherapy with curative or palliative intent; persistence with G-CSF therapy; discontinuation, delay, or reduction in chemotherapy administration; incidence of adverse events; compliance with pegfilgrastim therapy; and health-related quality of life (HRQoL).

This is an estimation study. The planned sample size is 2,220 patients in each subgroup (pegfilgrastim OBI and other physician choice) of the curative intent group; the final sample size is ≤5,440 patients (4,440 curative intent and ≤1,000 palliative intent). Expected FN incidence is 7.5% in the pegfilgrastim OBI group and 10% in the other physician choice group. Standardized log binomial regression will be used to estimate the adjusted incidence of FN, and depending on the sample size, the adjusted relative risk of FN for pegfilgrastim OBI vs other physician choice and for on-label pegfilgrastim OBI vs other physician choice. G-CSF persistence and compliance as well as HRQoL (measured using the 12-item Short Form Health Survey [SF-12] HRQoL instrument) will be determined for the pegfilgrastim OBI vs other physician choice groups. AEs will be graded according to NCI CTCAE Version 4.0.

As of 25 June 2019, 1,048 patients have been enrolled. For study information, contact Tatiana Lawrence at tlawrenc@amgen.com.

Citation Format: Reshma Mahtani, Jeffrey Crawford, Robert Rifkin, David Dale, Alan Brookhart, Prasad Gawade, Tatiana Lawrence, Rejesh Balani, Gary H Lyman. The incidence of febrile neutropenia (FN) for chemotherapy patients receiving pegfilgrastim by an on-body injector (pegfilgrastim OBI) versus other FN prophylaxis strategies [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT1-05-01.