Economic analysis of prophylactic pegfilgrastim in adult cancer patients receiving chemotherapy

Health economics of market access for biopharmaceuticals and biosimilars

BACKGROUND AND SCOPE

This article discusses health economic challenges of research and development, registration, pricing and reimbursement of biopharmaceuticals and biosimilars. A literature search was carried out of PubMed, Centre for Reviews and Dissemination databases, Cochrane Database of Systematic Reviews and EconLit up to March 2009.

FINDINGS

The development process of biopharmaceuticals is risky, lengthy, complex and expensive. Registration is complicated by the inherent variation between biopharmaceuticals. Also, as biopharmaceuticals are likely to be efficacious in a subgroup of the patient population, there is a need to select the most responsive target population and to identify biomarkers. To inform pricing and reimbursement decisions, the development process needs to collect comparative data to calculate the incremental cost effectiveness and budget impact of biopharmaceuticals. There is a role for innovative mechanisms such as risk-sharing arrangements to reimburse biopharmaceuticals.

CONCLUSIONS

Given that biosimilars are similar, but not identical to the reference biopharmaceutical, the development process needs to generate clinical trial data in order to gain marketing authorisation. From a health economic perspective, the question arises whether inherent differences between biopharmaceuticals and biosimilars produce differences in safety, effectiveness and costs: to date, this question is unresolved. The early inclusion of health economics in the process of developing biopharmaceuticals and biosimilars is imperative with a view to demonstrating their relative (cost) effectiveness and informing registration, pricing and reimbursement decisions.

Cost-effectiveness of pegfilgrastim versus filgrastim primary prophylaxis in women with early-stage breast cancer receiving chemotherapy in the United States

BACKGROUND

Prophylaxis with granulocyte colony-stimulating factor reduces the risk for febrile neutropenia (FN) in patients receiving myelosuppressive chemotherapy.

OBJECTIVE

We estimated the incremental cost-effectiveness of primary prophylaxis (starting in cycle 1 of chemotherapy) with pegfilgrastim versus filgrastim in women with early-stage breast cancer receiving myelosuppressive chemotherapy in the United States.

METHODS

A decision-analytic model was constructed from a health payer's perspective with a lifetime study horizon. The model considered direct medical costs and outcomes related to reduced FN and potential survival benefits due to reduced FN-related mortality and on-time receipt of full-dose chemotherapy. Sensitivity analyses were conducted.

RESULTS

Pegfilgrastim was cost-saving and more effective (ie, dominant strategy) than 11-day filgrastim. The incremental cost-effectiveness ratio (ICER) for pegfilgrastim versus 6-day filgrastim was $12,904 per FN episode avoided. Adding the survival benefit due to reduced FN mortality and receipt of optimal chemotherapy dose yielded an ICER of $31,511 per quality-adjusted life year (QALY) gained and $14,415 per QALY gained, respectively. The most influential factors included inpatient FN case-fatality rate, cost of pegfilgrastim and filgrastim, baseline probability of FN, relative risk for FN between filgrastim and pegfil-grastim, and cost of administration of filgrastim.

CONCLUSION

Pegfilgrastim was cost-saving compared with 11-day filgrastim and cost-effective compared with 6-day filgrastim from a health payer's perspective for the primary prophylaxis of FN in these women with early-stage breast cancer receiving myelosuppressive chemotherapy.

Emerging PEGylated drugs

PEGylation is a pharmaceutical technology that involves the covalent attachment of polyethylene glycol (PEG) to a drug to improve its pharmacokinetic, pharmacodynamic, and immunological profiles, and thus, enhance its therapeutic effect. Currently, PEGylation is used to modify proteins, peptides, oligonucleotides, antibody fragments, and small organic molecules. Research groups are striving to improve the consistencies of PEGylated drugs and to PEGylate commercialized proteins and small organic molecules. Furthermore, the PEGylations of novel medications, like oligonucleotides and antibody fragments, are being pursued to improve their bioavailabilities. This active research in the PEGylation field and the continued growth of the biopharmaceutical market predicts that PEGylated drugs have a bright future.

XM02, the first granulocyte colony-stimulating factor biosimilar, is safe and effective in reducing the duration of severe neutropenia and incidence of febrile neutropenia in patients with non-Hodgkin lymphoma receiving chemotherapy

Recombinant granulocyte colony-stimulating factors (G-CSFs) such as filgrastim or lenograstim are being used to treat chemotherapy-induced neutropenia. The aim of the present study was to investigate a new G-CSF, XM02, in comparison to filgrastim in terms of safety and efficacy in the prevention of chemotherapy-induced neutropenia in non-Hodgkin-lymphoma (NHL). A total of 92 patients receiving chemotherapy were randomised in cycle 1 to treatment with daily injections (subcutaneous 5 microg/kg/day) of XM02 (n = 63) or filgrastim (n = 29) for at least 5 days and a maximum of 14 days. In subsequent cycles, all patients received XM02. The mean duration of severe neutropenia (DSN) was 0.5 and 0.9 days in cycle 1 for XM02 and filgrastim, respectively (p = 0.1055). In cycle 1, the incidence of febrile neutropenia (FN) was 11.1% for XM02 and 20.7% for filgrastim (p = 0.1232). The adverse event profile was similar between XM02 and filgrastim. XM02 demonstrated equivalent efficacy and similar safety profile as the reference medication filgrastim. Treatment with XM02 is as beneficial as filgrastim in ameliorating severe neutropenia and FN in patients with NHL receiving chemotherapy. XM02 is safe and well tolerated in the doses applied in this study.

Enhanced circulation half-life of site-specific PEGylated rhG-CSF: optimization of PEG molecular weight

Recombinant human granulocyte colony stimulating factor (rhG-CSF) and its PEGylated product "mono-PEG20-GCSF" have already been widely used for treatment of all kinds of neutropenia. However, the high required dosage of mono-PEG20-GCSF made it relatively expensive in clinical use. We postulated that an N-terminal site-specific PEGylated rhG-CSF with higher PEG Mw (PEG30 kDa) might be able to achieve longer circulation half-life while retaining its bioactivity, allowing the reduction of dosage for clinical use. rhG-CSF was PEGylated at the N-terminus by 5 kDa, 10 kDa, 20 kDa and 30 kDa methoxy-poly(ethylene glycol)-propionaldehyde (mPEG-ALD), and the four PEGylates were compared with respect to reaction, separation, characterization and also in vivo/in vitro activity, results showed that the mPEG-ALD of higher Mw demonstrated better N-terminal site-specific selectivity, separation purity and yield. The production cost and in vitro activity of mono-PEG30-GCSF and mono-PEG20-GCSF were almost the same, while mono-PEG30-GCSF showed longer in vivo circulation half-life and 60% higher drug bioavailability than mono-PEG20-GCSF. Consequently, mono-PEG30-GCSF shall be administered at a lower dosage than mono-PEG20-GCSF while retaining the same therapeutic efficacy.

Cost-effectiveness of primary versus secondary prophylaxis with pegfilgrastim in women with early-stage breast cancer receiving chemotherapy

OBJECTIVE

Prophylaxis with granulocyte colony-stimulating factor (G-CSF) reduces the risk of febrile neutropenia (FN) in patients receiving myelosuppressive chemotherapy. We estimated the incremental cost-effectiveness of G-CSF pegfilgrastim primary (starting in cycle 1 and continuing in subsequent cycles of chemotherapy) versus secondary (only after an FN event) prophylaxis in women with early-stage breast cancer receiving myelosuppressive chemotherapy with a >or=20% FN risk.

METHODS

A decision-analytic model was constructed from a health insurer's perspective with a lifetime study horizon. The model considers direct medical costs and outcomes related to reduced FN and potential survival benefits because of reduced FN-related mortality. Inputs for the model were obtained from the medical literature. Sensitivity analyses were conducted across plausible ranges in parameter values.

RESULTS

The incremental cost-effectiveness ratio (ICER) of pegfilgrastim as primary versus secondary prophylaxis was $48,000/FN episode avoided. Adding survival benefit from avoiding FN mortality yielded an ICER of $110,000/life-year gained (LYG) or $116,000/quality-adjusted life-year (QALY) gained. The most influential factors included FN case-fatality, FN relative risk reduction from primary prophylaxis, and age at diagnosis.

CONCLUSIONS

Compared with secondary prophylaxis, the cost-effectiveness of pegfilgrastim as primary prophylaxis may be equivalent or superior to other commonly used supportive care interventions for women with breast cancer. Further assessment of the direct impact of G-CSF on short- and long-term survival is needed to substantiate these findings.

Cost-effectiveness of pegfilgrastim versus 6-day filgrastim primary prophylaxis in patients with non-Hodgkin's lymphoma receiving CHOP-21 in United States

OBJECTIVES

Prophylaxis with granulocyte-colony stimulating factor (G-CSF) reduces the risk of febrile neutropenia (FN) in patients receiving myelosuppressive chemotherapy. Randomized clinical trials have shown that pegfilgrastim, a 2nd-generation G-CSF, is at least as effective as the 1st-generation G-CSF filgrastim. In the meta-analysis of trials pegfilgrastim performed better than filgrastim with respect to FN risk. The incremental cost-effectiveness of primary prophylaxis (starting in cycle 1 and continuing in subsequent cycles of chemotherapy) with pegfilgrastim versus filgrastim used for 6 days (as is often used in clinical practice) was estimated in patients with aggressive non-Hodgkin's lymphoma (NHL) receiving myelosuppressive chemotherapy in the United States.

METHODS

A decision-analytic model was constructed from a health insurer's perspective with a life-time study horizon. The model considered direct medical costs and outcomes related to reduced FN and potential survival benefits due to reduced FN-related mortality. Inputs for the model were obtained from the medical literature. Sensitivity analyses were conducted across plausible ranges in parameter values.

RESULTS

The incremental cost-effectiveness (ICER) of pegfilgrastim versus 6-day filgrastim primary prophylaxis was $2167/FN episode avoided. Adding survival benefit from avoiding FN mortality yielded an ICER of $5532/LY gained or $6190/QALY gained. When the potential benefit of optimized chemotherapy was included, the ICER was $1494/LY gained or $1677/QALY gained. The most influential factors included cost of pegfilgrastim, relative risk of FN between pegfilgrastim and filgrastim, FN case-fatality rate, cost of filgrastim and baseline FN risk.

CONCLUSIONS

Pegfilgrastim is cost-effective in primary prophylaxis of FN compared to 6 days per cycle of filgrastim, in patients with NHL receiving myelosuppressive chemotherapy (e.g., cyclophosphamide + doxorubicin + vincristine + prednisolone [CHOP-21]) chemotherapy. Study limitations included lack of direct evidence linking G-CSF use with a reduction in FN-related mortality and limited data that show a relationship between relative dose intensity (RDI) and cancer-specific patient survival.