Trends in use of primary prophylactic colony stimulating factors and neutropenia-related hospitalization in commercially insured patients receiving myelosuppressive chemotherapy in the United States: 2005-2017

Two decades of pegfilgrastim: what have we learned? Where do we go from here?

Chemotherapy-induced febrile neutropenia (FN) is a medical emergency that may occur in patients with malignancies receiving myelosuppressive chemotherapy. FN requires early therapeutic intervention since it is associated with increased hospitalizations and high mortality risk of 5%-20%. FN-related hospitalizations are higher in patients with myeloid malignancies than in those with solid tumors due to the myelotoxicity of chemotherapy regimens and the compromised bone marrow function. FN increases the burden of cancer by causing chemotherapy dose reductions and delays. The administration of the first granulocyte colony-stimulating factor (G-CSF), filgrastim, reduced the incidence and duration of FN in patients undergoing chemotherapy. Filgrastim later evolved into pegfilgrastim, which has a longer half-life than filgrastim and was associated with a lower rate of severe neutropenia, chemotherapy dose reduction, and treatment delay. Nine million patients have received pegfilgrastim since its approval in early 2002. The pegfilgrastim on-body injector (OBI) is an innovative device facilitating the time-released auto-injection of pegfilgrastim approximately 27 hours after chemotherapy, as clinically recommended for the prevention of FN, thus eliminating the need for a next-day hospital visit. Since its introduction in 2015, one million patients with cancer have received pegfilgrastim using the OBI. Subsequently, the device has been approved in the United States (US), European Union, Latin America, and Japan, with studies and a postmarketing commitment demonstrating device reliability. A recent prospective observational study conducted in the US demonstrated that the OBI substantially improved the adherence to and compliance with clinically recommended pegfilgrastim therapy; patients receiving pegfilgrastim via the OBI experienced a lower incidence of FN than those receiving alternatives for FN prophylaxis. This review discusses the evolution of G-CSFs leading to the development of the OBI, current recommendations for G-CSF prophylaxis in the clinic, continued evidence supporting next-day pegfilgrastim administration, and improvements in patient care made possible with the OBI.

Risk of chemotherapy-induced febrile neutropenia in intermediate-risk regimens: Clinical and economic outcomes of granulocyte colony-stimulating factor prophylaxis

BACKGROUND: Chemotherapy-induced neutropenia increases the risk of febrile neutropenia (FN) and infection with resultant hospitalizations, with substantial health care resource utilization (HCRU) and costs. Granulocyte-colony stimulating factor (GCSF) is recommended as primary prophylaxis for chemotherapy regimens having more than a 20% risk of FN. Yet, for intermediate-risk (10%-20%) regimens, it should be considered only for patients with 1 or more clinical risk factors (RFs) for FN. It is unclear whether FN prophylaxis for intermediate-risk patients is being optimally implemented. OBJECTIVE: To examine RFs, prophylaxis use, HCRU, and costs associated with incident FN during chemotherapy. METHODS: This retrospective study used administrative claims data for commercial and Medicare Advantage enrollees with nonmyeloid cancer treated with intermediate-risk chemotherapy regimens during January 1, 2009, to March 31, 2020. Clinical RFs, GCSF prophylaxis, incident FN, HCRU, and costs were analyzed descriptively by receipt of primary GCSF, secondary GCSF, or no GCSF prophylaxis. Multivariable Cox regression analysis was used to examine the association between number of RFs and cumulative FN risk. RESULTS: The sample comprised 13,937 patients (mean age 67 years, 55% female). Patients had a mean of 2.3 RFs, the most common being recent surgery, were aged 65 years or greater, and had baseline liver or renal dysfunction; 98% had 1 or more RFs. However, only 35% of patients received primary prophylaxis; 12% received secondary prophylaxis. The hazard ratio of incident FN was higher with increasing number of RFs during the first line of therapy, yet more than 54% of patients received no prophylaxis, regardless of RFs. Use of GCSF prophylaxis varied more by chemotherapeutic regimen than by number of RFs. Among patients treated with rituximab, cyclophosphamide, hydroxydaunorubicin hydrochloride (doxorubicin hydrochloride), vincristine, and prednisone, 76% received primary prophylaxis, whereas only 22% of patients treated with carboplatin/paclitaxel received primary prophylaxis. Among patients with a first line of therapy FN event, 78% had an inpatient stay and 42% had an emergency visit. During cycle 1, mean FN-related coordination of benefits-adjusted medical costs per patient per month ($13,886 for patients with primary prophylaxis and $18,233 for those with none) were driven by inpatient hospitalizations, at 91% and 97%, respectively. CONCLUSIONS: Incident FN occurred more often with increasing numbers of RFs, but GCSF prophylaxis use did not rise correspondingly. Variation in prophylaxis use was greater based on regimen than RF number. Lower health care costs were observed among patients with primary prophylaxis use. Improved individual risk identification for intermediate-risk regimens and appropriate prophylaxis may decrease FN events toward the goal of better clinical and health care cost outcomes. DISCLOSURES: This work was funded by Sandoz Inc., which participated in the design of the study, interpretation of the data, writing and revision of the manuscript, and the decision to submit the manuscript for publication. The study was performed by Optum under contract with Sandoz Inc. The author(s) meet criteria for authorship as recommended by the International Committee of Medical Journal Editors. The authors received no direct compensation related to the development of the manuscript. Dr Li is an employee of Sandoz Inc. Drs Bell and Lal and Mr Peterson-Brandt were employees of Optum at the time of the study. Ms Anderson and Dr Aslam are employees of Optum. Dr Lyman has been primary investigator on a research grant from Amgen to their institution and has consulted for Sandoz, G1 Therapeutics, Partners Healthcare, BeyondSpring, ER Squibb, Merck, Jazz Pharm, Kallyope, Teva; Fresenius Kabi, Seattle Genetics, and Samsung.

Real-world cost-effectiveness of primary prophylaxis with G-CSF biosimilars in patients at intermediate/high risk of febrile neutropenia

Background: Real-world data suggests superiority of pegfilgrastim (PEG) over filgrastim (FIL) in reducing the incidence of chemotherapy-induced febrile neutropenia (FN), probably attributable to underdosed FIL in practice. We used real-world data to assess the cost-effectiveness of primary prophylaxis with PEG versus FIL in cancer patients at intermediate-to-high risk of FN from a US payer perspective. Methods: A Markov model with lifetime horizon. Results: For the high-risk group, PEG (vs FIL) biosimilars resulted in 0.43 FN events prevented (FNp), 0.27 quality-adjusted life-years gained (QALYg) and a cost saving of USD$5703. For the intermediate-risk group, PEG biosimilar led to 0.18 FNp and 0.12 QALYg, at USD$9674/FNp and USD$14,502/QALYg. Conclusion: PEG biosimilars may provide opportunities to optimize FN management in patients with intermediate-to-high FN risk.

Risk of chemotherapy-induced febrile neutropenia in patients with metastatic cancer not receiving granulocyte colony-stimulating factor prophylaxis in US clinical practice

Objectives

To evaluate the use of granulocyte colony-stimulating factor (G-CSF) prophylaxis in US patients with selected metastatic cancers and chemotherapy-induced febrile neutropenia (FN) incidence and associated outcomes among the subgroup who did not receive prophylaxis.

Methods

This retrospective cohort study was conducted at four US health systems and included adults with metastatic cancer (breast, colorectal, lung, non-Hodgkin lymphoma [NHL]) who received myelosuppressive chemotherapy (2009–2017). Patients were stratified by FN risk level based on risk factors and chemotherapy (low/unclassified risk, intermediate risk without any risk factors, intermediate risk with ≥ 1 risk factor [IR + 1], high risk [HR]). G-CSF use was evaluated among all patients stratified by FN risk, and FN/FN-related outcomes were evaluated among patients who did not receive first-cycle G-CSF prophylaxis.

Results

Among 1457 metastatic cancer patients, 20.5% and 28.1% were classified as HR and IR + 1, respectively. First-cycle G-CSF prophylaxis use was 48.5% among HR patients and 13.9% among IR + 1 patients. In the subgroup not receiving first-cycle G-CSF prophylaxis, FN incidence in cycle 1 was 7.8% for HR patients and 4.8% for IR + 1 patients; during the course, corresponding values were 16.9% and 15.9%. Most (> 90%) FN episodes required hospitalization, and mortality risk ranged from 7.1 to 26.9% across subgroups.

Conclusion

In this retrospective study, the majority of metastatic cancer chemotherapy patients for whom G-CSF prophylaxis is recommended did not receive it; FN incidence in this subgroup was notably high. Patients with elevated FN risk should be carefully identified and managed to ensure appropriate use of supportive care.

Electronic supplementary material

The online version of this article (10.1007/s00520-020-05715-3) contains supplementary material, which is available to authorized users.