Clinical efficacy of adjunctive G-CSF on solid tumor and lymphoma patients with established febrile neutropenia

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.

Cost-effectiveness analysis of pegfilgrastim in patients with non-small cell lung cancer receiving ramucirumab plus docetaxel in Japan

PURPOSE

The dose-limiting factor of ramucirumab plus docetaxel (RAM + DTX) in patients with non-small cell lung cancer (NSCLC) is febrile neutropenia (FN), which has a high incidence in Asians. This study aimed to evaluate the cost-effectiveness of pegfilgrastim (Peg-G) in patients with NSCLC receiving RAM + DTX in Japan.

METHODS

We simulated model patients treated with RAM + DTX in Japan and developed a decision-analytical model for patients receiving Peg-G prophylaxis or no primary prophylaxis. The expected cost, quality-adjusted life-year (QALY), and incremental cost-effectiveness ratio (ICER) of each treatment were calculated from the perspective of a Japanese healthcare payer. The willingness-to-pay (WTP) threshold was set at 45,867 United States dollars (USD) (5 million Japanese yen) per QALY gained. The probabilities, utility values, and other costs were obtained from published sources. Deterministic sensitivity analysis (DSA) and probabilistic analysis were conducted to evaluate the effect of each parameter and robustness of the base-case results.

RESULTS

The expected cost and QALYs were 20,275 USD and 0.701 for Peg-G prophylaxis and 17,493 USD and 0.672 for no primary prophylaxis, respectively. The ICER was calculated to be 97,519 USD per QALY gained. The results were most sensitive to FN risk with Peg-G. When FN risk with no primary prophylaxis exceeded 51% or the cost of Peg-G was less than 649 USD per injection, the ICER was below the WTP threshold. The probabilistic analysis revealed a 9.1% probability that the ICER was below the WTP threshold.

CONCLUSION

Peg-G is not cost-effective in patients with NSCLC receiving RAM + DTX in Japan.

Association between Breast Cancer Polygenic Risk Score and Chemotherapy-Induced Febrile Neutropenia: Null Results

BACKGROUND

The hypothesis that breast cancer (BC) susceptibility variants are linked to chemotherapy-induced toxicity has been previously explored. Here, we investigated the association between a validated 313-marker-based BC polygenic risk score (PRS) and chemotherapy-induced neutropenia without fever and febrile neutropenia (FNc) in Asian BC patients.

METHODS

This observational case-control study of Asian BC patients treated with chemotherapy included 161 FNc patients, 219 neutropenia patients, and 936 patients who did not develop neutropenia. A continuous PRS was calculated by summing weighted risk alleles associated with overall, estrogen receptor- (ER-) positive, and ER-negative BC risk. PRS distributions neutropenia or FNc cases were compared to controls who did not develop neutropenia using two-sample t-tests. Odds ratios (OR) and corresponding 95% confidence intervals were estimated for the associations between PRS (quartiles and per standard deviation (SD) increase) and neutropenia-related outcomes compared to controls.

RESULTS

PRS distributions were not significantly different in any of the comparisons. Higher PRS_overall quartiles were negatively correlated with neutropenia or FNc. However, the associations were not statistically significant (PRS per SD increase OR neutropenia: 0.91 [0.79-1.06]; FNc: 0.87 [0.73-1.03]). No dose-dependent trend was observed for the ER-positive weighted PRS (PRS_ER-pos) and ER-negative weighted PRS (PRS_ER-neg).

CONCLUSION

BC PRS was not strongly associated with chemotherapy-induced neutropenia or FNc.

Appropriateness of using granulocyte colony-stimulating factor (G-CSF) for primary prophylaxis of febrile neutropenia in solid tumors

INTRODUCTION

Febrile neutropenia (FN) is one of the dose-limiting adverse effects of chemotherapy. Granulocyte-Colony Stimulating Factors (G-CSFs) minimize the incidence of FN and reduce the risk of neutropenia complications. This study was conducted to address the prescription pattern of G-CSF for primary prophylaxis of FN during the first cycle of chemotherapy in solid tumors.

METHOD

This prospective observational study was done to investigate the G-CSF prescription pattern in patients receiving the first cycle of chemotherapy for solid tumors and compare it with the NCCN guideline recommendations.

RESULT

Based on the guideline, prophylactic G-CSF administration was indicated in 26 of the 96 patients (27.1%) and all of them received G-CSF. On the other hand, 70 patients (72.9%) did not meet the guideline criteria for prophylaxis, but 60 (62.5%) of them received G-CSF. Seven doses of pegfilgrastim and 165 doses of filgrastim were used inappropriately in the study population, which was associated with an economic burden of about 224.7 million IRR (5350 USD).

CONCLUSION

Taken together, inconsistencies with the guideline were observed in this prospective evaluation, suggesting that submitting rationalized policies to decrease G-CSF prescription, especially in patients with a lower or intermediate FN risk, yields substantial cost savings.

Routine Primary Prophylaxis for Febrile Neutropenia with Biosimilar Granulocyte Colony-Stimulating Factor (Nivestim) or Pegfilgrastim Is Cost Effective in Non-Hodgkin Lymphoma Patients undergoing Curative-Intent R-CHOP Chemotherapy

OBJECTIVE

This study aims to compare the cost-effectiveness of various strategies of myeloid growth factor prophylaxis for reducing the risk of febrile neutropenia (FN) in patients with non-Hodgkin lymphoma in Singapore who are undergoing R-CHOP chemotherapy with curative intent.

METHODS

A Markov model was created to compare seven prophylaxis strategies: 1) primary prophylaxis (PP) with nivestim (biosimilar filgrastim) throughout all cycles of chemotherapy; 2) PP with nivestim during the first two cycles of chemotherapy; 3) secondary prophylaxis (SP) with nivestim; 4) PP with pegfilgrastim throughout all cycles of chemotherapy; 5) PP with pegfilgrastim during the first two cycles of chemotherapy; 6) SP with pegfilgrastim; and 7) no prophylaxis (NP). The perspective of a hospital was taken and cost-effectiveness was expressed as the cost per episode of FN avoided over six cycles of chemotherapy. A probabilistic sensitivity analysis was conducted.

RESULTS

Strategies 3, 6, and 7 were dominated in the base case analysis by strategy 5. The costs associated with strategies 2, 5, 1, and 4 were US$3,813, US$4,056, US$4,545, and US$5,331, respectively. The incremental cost-effectiveness ratios for strategy 5 vs. strategy 2, strategy 1 vs. strategy 5, and strategy 4 vs. strategy 1 were US$13,532, US$22,565, and US$30,452, respectively, per episode of FN avoided. Strategy 2 has the highest probability to be cost-effective (ranged from 48% to 60%) when the willingness to pay (WTP) threshold is lower than US$10,000 per FN episode prevented.

CONCLUSION

In Singapore, routine PP with granulocyte colony-stimulating factor (nivestim or pegfilgrastim) is cost-effective for reducing the risk of FN in patients receiving R-CHOP.

Risk Factors for Predicting Severe Neutropenia Induced by Pemetrexed Plus Carboplatin Therapy in Patients with Advanced Non-small Cell Lung Cancer

Pemetrexed plus carboplatin therapy is widely administered to patients with non-squamous non-small cell lung cancer. Although severe neutropenia is often observed during this combination therapy, its predictive factors are unknown. Therefore, we investigated the predictive factors for severe neutropenia in 77 patients treated with this combination therapy at the Department of Respiratory Medicine, Kyushu University Hospital, between September 2009 and September 2013. All data were retrospectively collected from the electronic medical record system, and univariate and multivariate logistic regression analyses were performed to identify risk factors for grade 3 or 4 neutropenia. Among the 77 patients, 34 (44%) developed grade 3 or 4 neutropenia. Multivariate analysis revealed that lower baseline hemoglobin values (odds ratio [OR], 1.97 per 1 g/dL decrease; 95% confidence interval [CI], 1.39-2.99, p<0.01) and lower baseline neutrophil counts (OR, 1.71 per 1000/mm(3) decrease; 95% CI, 1.14-2.71, p=0.01) were significantly associated with grade 3 or 4 neutropenia. During 4 courses of pemetrexed plus carboplatin therapy, the incidence of grade 3 or 4 neutropenia in patients with baseline hemoglobin values of <11.6 g/dL was significantly higher than that in patients with values of ≥11.6 g/dL [84% (16/19) vs. 31% (18/58), p<0.001]. In conclusion, patients with lower baseline neutrophil counts or lower baseline hemoglobin values, especially those with baseline hemoglobin values of <11.6 g/dL, should be monitored more carefully during pemetrexed plus carboplatin therapy.

Economic burden of chemotherapy-induced febrile neutropenia in patients with lymphoma: a systematic review

The primary objective of this review was to identify the cost components that were most frequently associated with the economic burden of febrile neutropenia (FN) among patients with lymphoma. The secondary objective was to identify any parameter associated with higher FN cost. Ten cost of illness (COI) studies were identified. General characteristics on study design, country, perspective, and patient population were extracted and systematically reported. It was observed that majority (70%) of the studies employed the perspective of healthcare provider. 20% of the studies considered long-term costs. Estimated costs were adjusted to 2013 US dollars and ranged from US$5819 to US$34,756. The cost components that were most frequently associated with economic burden were ward and medication costs. Inpatient management, male gender, discharged dead, and comorbidity were positively associated with higher FN costs. Future COI studies on FN should focus on the accurate estimation on ward and medication costs.

Costs associated with febrile neutropenia in solid tumor and lymphoma patients - an observational study in Singapore

Background

The primary objective was to describe the total direct inpatient costs among solid tumor and lymphoma patients with chemotherapy-induced febrile neutropenia (FN) and the factors that were associated with higher direct cost. The secondary objective was to describe the out-of-pocket patient payments and the factors that were associated with higher out-of-pocket patient payments.

Methods

This was a single-center observational study conducted at the largest cancer center in Singapore. All of the adult cancer patients hospitalized due to FN from 2009 to 2012 were studied. The primary outcomes were the total hospital cost and the out-of-pocket patient payments (adjusted by government subsidy) per FN episode. Univariate analysis and multiple linear regression were conducted to identify the factors associated with higher FN costs.

Results

Three hundred and sixty seven adult cancer patients were documented with FN-related hospitalizations. The mean total hospital cost was US$4,193 (95% CI: US$3,779-4,607) and the mean out-of-pocket patient payment was US$2,230 (95% CI: US$1,976-2,484), per FN episode. The factors associated with a higher total hospital cost were longer length of stay, severe sepsis, and lymphoma as underlying cancer. The out-of-pocket patient payment was positively associated with longer length of stay, severe sepsis, lymphoma diagnosed as underlying cancer, the therapeutic use of granulocyte colony-stimulating factor (GCSF), the private ward class, and younger patients.

Conclusions

The total hospital cost and out-of-pocket patient payments of FN management in lymphoma cases were substantial compared with other solid tumors. Factors associated with a higher FN management cost may be useful for developing appropriate strategies to reduce the cost of FN for cancer patients.