The use of darbepoetin alfa for the treatment of chemotherapy-induced anaemia

Chemotherapy-induced anaemia, with its important consequences on quality of life and social function of cancer patients, can be improved with erythropoietic therapy. Darbepoetin alfa is the first of a novel generation of erythropoietic proteins with a unique molecular structure and a circulating half-life that is threefold longer than that of the previous recombinant human erythropoietin. The efficacy and safety of weekly administration have been confirmed in different Phase II and III randomised trials. In order to optimise the efficacy profile of darbepoetin alfa, extended dosing intervals and front-loading regimens are evaluated, as well the optimal haemoglobin level to initiate therapy. Across all trials, darbepoetin alfa was shown to be a well-tolerated and safe therapy. The possible favourable effect on the outcome of cancer patients needs to be further elucidated.     

Darbepoetin alfa: a review of its use in the treatment of anaemia in patients with cancer receiving chemotherapy

Darbepoetin alfa (Aranesp) is an analogue of recombinant human erythropoietin (rHuEPO) produced using recombinant DNA technology. The high number of sialic acid moieties in darbepoetin alfa results in a prolonged half-life and enhanced in vivo biological activity compared with rHuEPO (as demonstrated in animal studies) and permits a reduction in the frequency of administration.Subcutaneous darbepoetin alfa 2.25 microg/kg once weekly or 500 microg once every 3 weeks (with a provision for dose adjustments) is an effective and well tolerated erythropoietic agent in anaemic patients with cancer receiving chemotherapy. In randomised, controlled clinical trials, the drug increased haemoglobin levels and reduced the need for blood transfusions in patients with various types of nonmyeloid malignancies and also ameliorated anaemia-related fatigue, thereby improving their health-related quality of life (HR-QOL) scores. The once-every-3-weeks dosage regimen provides further convenience by offering the possibility of synchronising its administration with most chemotherapy regimens. Direct comparisons between approved dosages of darbepoetin alfa and other erythropoietic agents have not been conducted. Such comparisons would be very helpful in formulating definitive conclusions about their relative efficacy and cost effectiveness. Darbepoetin alfa provides an effective and well tolerated treatment option for the treatment of anaemia in patients with cancer receiving chemotherapy.     

Dose and cost comparison of erythropoietic agents in the inpatient hospital setting.

PURPOSE: The inpatient dosing patterns and treatment costs in cancer and predialysis chronic kidney disease (CKD) patients treated with erythropoietic agents from a hospital pharmacy perspective were studied. METHODS: An analysis of electronic inpatient records from the Premier Perspective comparative hospital database was conducted. Study participants were identified through hospitalizations recorded between July 2002 and March 2005 from over 500 hospitals nationwide. Adult patients with an admitting diagnosis of cancer or predialysis CKD and treated with epoetin alfa or darbepoetin alfa during hospitalization were included. Patients who had received renal dialysis or both agents during a hospitalization were excluded. Wholesale acquisition costs from September 2006 were used to calculate drug costs. RESULTS: A total of 25,645 hospitalized patients with cancer (22,873 received epoetin alfa; 2,772 received darbepoetin alfa) and 66,822 hospitalized patients with CKD (60,079 received epoetin alfa; 6,743 received darbepoetin alfa) were identified. The mean cumulative dose per hospitalization resulted in dose ratios of 245:1 and 242:1 (units epoetin alfa:micrograms darbepoetin alfa) for cancer and CKD patients, respectively. On the basis of the cumulative dose per hospitalization, drug costs for darbepoetin alfa-treated patients were approximately 50% higher than drug costs for epoetin alfa-treated patients for both oncology and CKD patients. CONCLUSION: Epoetin alfa was associated with less cost compared with darbepoetin alfa for treating inpatients with cancer or CKD. Further research including the patients' clinical outcomes is necessary to determine the true pharmacoeconomic differences between the two agents.     

Darbepoetin alfa: new indication/new dosage. No proven advantage in chemotherapy-induced anaemia

(1) Current treatments for anaemia in patients receiving cancer chemotherapy include blood transfusion and epoetin alfa and beta. These epoetins correct anaemia in 40% to 65% of patients and reduce the number of patients who require transfusions during the second and third months of treatment by 12-35% in absolute terms. (2) Darbepoetin alfa is slightly more glycosylated than epoetin alfa and beta. It is no more effective than these two drugs in chronic renal failure. Darbepoetin alfa is now approved for the treatment of anaemia in patients who are receiving chemotherapy for non myeloid malignancies. (3) Two placebo-controlled dose-finding studies and two placebo-controlled trials involving nearly 1000 patients in total have shown that darbepoetin alfa decreases the number of transfused patients by 17-25% in absolute terms, and that it probably reduces fatigue. However, one-quarter of patients receiving darbepoetin were nonetheless transfused. (4) In the absence of reliable comparisons, there is no firm evidence that darbepoetin alfa is more effective than other epoetins. (5) According to relatively imprecise company reports, darbepoetin alfa increased the risk of thromboembolic events during clinical trials (6% versus 3%), including pulmonary embolism (1.3% versus 0%); the company also states that darbepoetin alfa does not increase the risk of arterial hypertension, a classical effect of epoetin that is mentioned in the summary of product characteristics (SPC). Placebo-controlled trials and dose-finding studies show no impact on the outcome of cancer, but follow-up is limited and a negative effect cannot be ruled out. The company states that no cases of erythroblastopenia have occurred among more than 70 000 treated patients. (6) According to the SPC, darbepoetin alfa can be given once a week. However, the optimal epoetin dosing schedule is unknown. Epoetin therapy takes several weeks to correct anaemia, whereas transfusion is immediately effective. (7) In practice, darbepoetin alfa seems a little easier to administer than epoetin alfa or beta, but the advantages and disadvantages of these drugs as compared with blood transfusion are not entirely clear.     

Erythropoietic therapy for the treatment of anemia in patients with cancer: a valuable clinical and economic option

ABSTRACT

Background: Healthcare organizations must evaluate the cost effectiveness of the alternative therapies that are available to treat anemia and improve quality of life (QoL) of patients with cancer, that is, erythropoietic protein therapy and blood transfusion.

Methods: Pharmacoeconomic studies that evaluated the cost of not treating anemia or treating with transfusion or erythropoietic protein therapy were reviewed and compared. Studies of individual erythropoietic proteins (epoetin alfa, epoetin beta or darbepoetin alfa) were also assessed. As no prospective trials have compared the erythropoietic proteins, retrospective studies and the results of separate trials were analyzed. The database searched for this review was PubMed (open date to August 2006). Recent conference abstracts were also searched (2003 – July 2006).

Results: There is a high cost associated with anemia in cancer patients. Treatment of anemia is likely to lead to increased hemoglobin (Hb) levels and improved QoL as principal outcomes. Therefore, in assessing erythropoietic protein versus transfusion, it is more appropriate to use Hb or QoL as endpoint rather than quality adjusted life year. Studies with the former approach showed that erythropoietic protein therapy is more cost effective than transfusion. Also, its cost effectiveness should be improved with the use of evidence-based guidelines for patient selection and more tailored utilization. Increasing evidence suggests there might be differences among the erythropoietic proteins in terms of response rate, speed of response, and need for dose escalation.

Conclusion: Significant costs are incurred when anemia in cancer is not treated. Erythropoietic protein therapy is more cost effective than blood transfusion for the treatment of cancer-related anemia. Transfusion should be reserved for patients with poor responses to erythropoietic protein or for the emergency setting, when rapid improvement in Hb is required.     

Darbepoetin alfa: a novel erythropoiesis-stimulating protein

Darbepoetin alfa is a novel erythropoiesis-stimulating protein developed for the treatment of anemia. It is a hyperglycosylated analog of recombinant human erythropoietin with the same mechanism of action as erythropoietin, but with a three-fold longer terminal half-life after intravenous administration than recombinant human erythropoietin and the native hormone both in animal models and in humans. Clinical studies in patients with chronic renal failure either receiving or not receiving dialysis have shown that darbepoetin alfa is equivalent to recombinant human erythropoietin in terms of increases in hemoglobin concentration, percentage of patients achieving target hemoglobin concentration and average time to reach target hemoglobin concentration, although darbepoetin alfa is administered less frequently (once weekly or every other week). Clinical trials in cancer patients either receiving or not receiving chemotherapy have demonstrated that darbepoetin alfa is safe and effective in alleviating anemia at dose intervals of once every 1, 2 or 3 weeks, and results suggest that it may achieve greater and more rapid responses than recombinant human erythropoietin in cancer patients. Furthermore, an improvement in health-related quality of life has been observed in association with anemia correction using darbepoetin alfa therapy in these patients. Darbepoetin alfa has been approved for intravenous and subcutaneous administration by the European Commission and the FDA for the treatment of anemia in patients with chronic renal failure. Additionally, this product was recently approved by the FDA for the treatment of anemia in patients with nonmyeloid malignancies where anemia is due to the effect of concomitantly administered chemotherapy. The recommended starting dose in chronic renal failure patients is 0.45 microg/kg once weekly for both intravenous and subcutaneous administration, with subsequent titration based on the hemoglobin concentration. In cancer patients, the recommended starting dose is 2.25 microg/kg once weekly by subcutaneous injection and subsequent titration. The adverse event profile of darbepoetin alfa is similar to that of recombinant human erythropoietin in both settings. There are no reports of antibody formation associated with darbepoetin alfa in chronic renal failure patients, and three cases of antibody formation, with neutralizing activity in one of the cases, have been reported in cancer patients. However, no cases of antibody-mediated pure red cell aplasia have been reported. The longer half-life of darbepoetin alfa, together with a similar efficacy and safety profile, confers the clinical advantage over recombinant human erythropoietin of allowing a less frequent dosing (once weekly or every other week versus one to three times weekly in renal patients), thus reducing health-care utilization and probably improving patient compliance.     

Utilization of darbepoetin alfa and epoetin alfa for chemotherapy-induced anemia.

PURPOSE: The patterns of use and effectiveness of therapy with darbepoetin alfa and epoetin alfa for chemotherapy-induced anemia (CIA) in hospital outpatient and community settings were evaluated. METHODS: Data were collected from medical charts at 65 oncology clinics in hospital outpatient and community settings for consecutive patients who received the first dose of either darbepoetin alfa or epoetin alfa between August 1, 2002, and February 15, 2003, and were to have had 12 weeks of follow-up data. RESULTS: Data from the charts of 3123 patients were abstracted. Of these patients, 2785 were treated with only one erythropoietic agent (1444 with darbepoetin alfa and 1341 with epoetin alfa) and were included in the analysis. The most common initial dosage of darbepoetin alfa was 200 microg every two weeks (61% of darbepoetin alfa recipients), and the most common initial dosage of epoetin alfa was 40,000 units weekly (72%). With these regimens, the dosage was escalated for 22% of darbepoetin alfa recipients and 23% of epoetin alfa recipients at a median of six weeks after the initial dose. The mean change from baseline in hemoglobin concentration after 12 weeks of therapy was similar for both groups, as was the percent of patients with red-blood-cell transfusions during treatment. CONCLUSION: The most common initial dosage of darbepoetin alfa for CIA was 200 microg every two weeks, and the most common initial dosage of epoetin alfa was 40,000 units weekly. At these dosages, the two agents appear to have similar clinical effectiveness.     

The advantages of intravenous renal anaemia treatment in an undernourished patient with chronic kidney disease

The subcutaneous (SC) treatment of renal anaemia in undernourished patients has potential limitations. In this case report we demonstrate the value of intravenous (IV) darbepoetin alfa in such a patient who experienced difficulty tolerating SC recombinant human erythropoietin (rHuEPO) therapy due to severe malnutrition. Intravenous treatment of renal anaemia in a malnourished patient is preferred because the absence of SC fat makes SC administration difficult. In such patients, darbepoetin alfa is the treatment of choice as it is administered less frequently than other erythropoietic therapies and is more effective at maintaining target haemoglobin (Hb) concentrations. In contrast to rHuEPO, darbepoetin alfa also has the additional advantage of bioequivalent IV and SC dose requirements.     

The advantages of intravenous renal anaemia treatment in an undernourished patient with chronic kidney disease

SUMMARY

The subcutaneous (SC) treatment of renal anaemia in undernourished patients has potential limitations. In this case report we demonstrate the value of intravenous (IV) darbepoetin alfa in such a patient who experienced difficulty tolerating SC recombinant human erythropoietin (rHuEPO) therapy due to severe malnutrition. Intravenous treatment of renal anaemia in a malnourished patient is preferred because the absence of SC fat makes SC administration difficult. In such patients, darbepoetin alfa is the treatment of choice as it is administered less frequently than other erythropoietic therapies and yis more effective at maintaining target haemoglobin (Hb) concentrations. In contrast to rHuEPO, darbepoetin alfa also has the additional advantage of bioequivalent IV and SC dose requirements.     

Reengineering clinical operations in a medical practice to optimize the management of anemia of chronic kidney disease

OBJECTIVES: To describe the clinic design, clinical evaluations, and treatment approaches used in a multidisciplinary clinic for management of anemia of chronic kidney disease (CKD), and to evaluate several selected clinical outcomes associated with this approach to anemia management. SETTING: University-affiliated, division of nephrology, outpatient multidisciplinary model CKD clinic headed by a clinical pharmacist. PATIENTS: One hundred sixty-six patients with anemia of CKD who were referred by nephrologists and primary care providers to the multidisciplinary clinic from March 1, 2002-July 31, 2004. MEASUREMENTS AND MAIN RESULTS: Patients received darbepoetin alfa dosed on an every-other-week basis. If patients were already receiving once-weekly recombinant human erythropoietin (r-HuEPO), the darbepoetin alfa dose was calculated by using the darbepoetin alfa package insert conversion table. If patients were na?ve to previous erythropoietic therapy, the darbepoetin alfa dose was either 60 microg or 0.7 microg/kg. The dose and frequency of darbepoetin alfa and oral iron supplements were adjusted to achieve the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (K/DOQI) targets for hemoglobin levels and iron measures. The primary outcome analyzed was the proportion of patients with at least 30 days of treatment who achieved a target hemoglobin level of 11.0 g/dl or greater. Of 128 patients who received at least 30 days of treatment, 100 (78%) attained the hemoglobin level (mean +/- SD 11.7 +/- 7 g/dl). Ninety-nine of 128 patients were originally na?ve to erythropoietic therapy; 77 (78%) of these 99 patients achieved the hemoglobin target in a mean +/- SD of 7.9 +/- 7.5 weeks. These data contrast with the data of 29 patients seen in the year previous to the reengineered clinic process, whereby only 12 (41%) of these comparable patients reached hemoglobin target with r-HuEPO therapy. Of the 77 previously erythropoietic-na?ve patients, 82% were receiving darbepoetin alfa every other week, 14% every 3 weeks, and 4% every 4 weeks at the time the hemoglobin target was achieved. Oral iron administration significantly increased the chance of achieving the K/DOQI targets for hemoglobin and iron. CONCLUSION: Redefining roles and practices of members of a clinical practice and reengineering processes for anemia management were effective in achieving and maintaining target hemoglobin and iron levels.     

Darbepoetin alfa: an effective treatment with flexible and simplified dosing for anemia in patients with cancer

Anemia is common in patients with cancer or myelodysplastic syndrome. Erythropoietic therapy offers an effective way to manage anemia by increasing hemoglobin levels, decreasing transfusion requirements, and alleviating symptoms. We reviewed data showing the feasibility and effectiveness of treatment with the erythropoiesis-stimulating protein darbepoetin alfa at extended dosing intervals to treat anemia in patients with cancer receiving multicycle chemotherapy. We also explored the darbepoetin alfa's potential for treating anemia in patients with myelodysplastic syndrome. Data from clinical studies and drug therapy evaluations confirm that darbepoetin alfa administered weekly, every 2 weeks, and every 3 weeks corrects and maintains hemoglobin levels in patients with chemotherapy-induced anemia. In addition, the data demonstrate that both weight-based and fixed dosing with darbepoetin alfa are effective, and that early intervention to treat anemia has clinical benefits. Darbepoetin alfa also is an effective treatment for anemia in patients with cancer not receiving chemotherapy, at extended dosing intervals of at least 3 weeks. Extended dosing for anemia treatment can provide benefits for patients, caregivers, and clinicians because it reduces the number of clinic visits needed and permits synchronizing anemia treatment with chemotherapy cycles. Data from recent studies suggest that darbepoetin alfa is effective for treating anemia in patients with myelodysplastic syndrome; this potential use is being investigated further in ongoing studies. Thus, darbepoetin alfa is an attractive therapy option for patients with chemotherapy or cancer-induced anemia. It allows increased flexibility and simplified dosing and may offer some benefit in the treatment of anemia in patients with myelodysplastic syndrome.     

Clinical and economic comparison of epoetin alfa and darbepoetin alfa

BACKGROUND: The pharmacoeconomics of erythropoietic therapy for the treatment of anemia is receiving renewed attention due to the current availability of two agents. Epoetin alfa has been the standard of therapy for patients with renal disease and cancer-related anemia for more than a decade. Darbepoetin alfa, an alternative agent, is now approved for anemia resulting from renal disease and cancer chemotherapy. METHODOLOGY: Although direct comparative trials have not been performed with these agents, information published in the last several years regarding their clinical efficacy, safety, and dosing is sufficient, in most cases, to compare costs. With the disclaimer that any efficacy comparison of competing products using published reports has certain limitations, a cost-minimization approach from a provider's perspective was conducted. RESULTS: To provide background for the economic evaluation, pharmacokinetic and pharmacodynamic data for these two agents are discussed. Recent clinical trials in the nephrology and oncology therapeutic areas are summarized, highlighting study designs, dosing regimens, patient entry criteria, study endpoints, and published results. Cost data, based on average wholesale prices (AWP) in 2003, are compared and calculated from available clinical data with an emphasis on efficacy. CONCLUSION: These evaluations largely conclude that epoetin alfa is the better pharmacoeconomic value of the two currently available erythropoietic agents.     

An extended terminal half-life for darbepoetin alfa: results from a single-dose pharmacokinetic study in patients with chronic kidney disease not receiving dialysis

BACKGROUND AND OBJECTIVE: Anaemia is a major and persistent manifestation of chronic kidney disease (CKD) caused by the deficient production of erythropoietin in the kidneys, the prevalence of which is proportional to the deterioration in kidney function. Darbepoetin alfa, an erythropoiesis-stimulating protein, exhibits a lower clearance and longer terminal half-life in serum than recombinant human erythropoietin, thereby allowing for a reduced dosing frequency. A recent study in patients with CKD, using a 4-week sampling period, suggested that the terminal half-life of darbepoetin alfa in serum is longer than that reported in previous studies, which were based on a 1-week sampling period. This study was conducted to characterise the pharmacokinetic profile of a single subcutaneous dose of darbepoetin alfa 1 microg/kg in patients with CKD, using a sampling duration of 4 weeks, which was hypothesised to allow better characterisation of the terminal half-life in serum. METHODS: Twenty patients with CKD not on dialysis, with a calculated glomerular filtration rate of 20-60 mL/min and who had not been treated with erythropoietic agents in the previous 12 weeks, were enrolled into this single-dose, open-label study. Patients received a single subcutaneous dose of darbepoetin alfa (Aranesp) 1 microg/kg on day 1, and blood samples were collected for pharmacokinetic analyses predose, 6 and 12 hours postdose and up to 28 days postdose. Seroreactivity sampling and further safety laboratory tests (clinical chemistry and urinalysis) were also performed. Patients were assessed for adverse events at each study visit. The primary endpoint was characterisation of the terminal half-life following a single subcutaneous dose of darbepoetin alfa 1 microg/kg. RESULTS: The mean terminal half-life in serum of darbepoetin alfa was determined to be 69.6 hours. Peak serum concentrations were reached in a median time of 36 hours postdose, and a mean apparent clearance of 3.51 mL/h/kg was comparable to that observed previously in this patient population. CONCLUSION: Based on an extended sampling schedule of 4 weeks, the terminal half-life of darbepoetin alfa was approximately 70 hours. This is longer than the 48.8 hours reported previously in patients with CKD on dialysis. These data suggest that the pharmacokinetic properties of darbepoetin alfa make this erythropoietic agent well suited to an extended dosing regimen.     

Guidelines and recommendations for the management of anaemia in patients with lymphoid malignancies

Patients with lymphoid malignancies frequently require repetitive and intensive anticancer treatments to induce and maintain disease remission. Anaemia (haemoglobin [Hb] <12 g/dL) is a common and debilitating problem associated with both the malignancy itself and its treatment burden. Anaemia negatively impacts on all aspects of patient quality of life (QOL) and treatment outcomes and survival, particularly in this disease setting.Widely acknowledged goals of anaemia treatment include Hb correction to approximately 12 g/dL, reduction in transfusion requirements and optimisation of patient QOL. Since the introduction of recombinant human erythropoietic therapy, transfusion (once the only anaemia treatment option available) is now primarily reserved for non-responders or those with severe or life-threatening anaemia. Data from randomised, double-blind, placebo-controlled studies, and large, non-randomised, open-label, community-based studies, along with almost 15 years of practical experience, support the assertion that epoetin alfa administered at a dosage of 150-300 U/kg three times weekly or 40,000-60,000U once weekly, both of which are US FDA-approved dose administration schedules, can effectively and safely achieve anaemia treatment goals for the majority of patients with lymphoid malignancies. Data and practical experience collected over the last 5 years on another erythropoietic agent with a slightly longer half-life but lower binding affinity, darbepoetin alfa, show that this agent when administered according to the FDA-approved dose administration schedules (2.25-4.5 microg/kg once weekly or 500microg once every 3 weeks) or according to a commonly-administered dose in clinical practice (3.0-5.0 microg/kg once every 2 weeks) can also effectively and safely correct anaemia, reduce transfusion requirements and improve QOL in many patients with lymphoid malignancies. One comparative head-to-head trial suggested that epoetin alfa might be superior to darbepoetin alfa in anaemic cancer patients receiving chemotherapy with respect to timing and magnitude of Hb correction, although further study is necessary, especially concerning optimal dose administration. Alternative dose administration schedules, such as epoetin alfa 80,000U every 2 weeks from initiation or 80,000U every 3 weeks following initiation with once weekly administration and darbepoetin alfa 4.5 microg/kg every 3 weeks following initiation with once weekly administration, are being actively investigated with the goal of increased flexibility for patients and healthcare providers.The treatment of anaemia in patients with lymphoid malignancies is an important part of overall disease management, as evidenced by continuous investigation of existing erythropoietic agents and new agents. Although treatment guidelines issued by organisations such as the National Comprehensive Cancer Network (NCCN) and American Society of Hematology (ASH)/American Society of Clinical Oncology (ASCO) suggest intervention with erythropoietic therapy when Hb falls below 10-11 g/dL or based on clinical symptoms, data suggest that anaemia is vastly under-recognised and under-treated. Clearly, an update on the definition, identification and optimal management of anaemia in patients with lymphoid malignancies is warranted.     

Extended-dosage-interval regimens of erythropoietic agents in chemotherapy-induced anemia.

PURPOSE: The safety and efficacy of extended-dosage-interval regimens of erythropoiesis-stimulating agents (ESAs) for managing chemotherapy-induced anemia (CIA) are reviewed. SUMMARY: Anemia is a frequent complication of chemotherapy. The ESAs epoetin alfa and darbepoetin alfa have been shown to safely and effectively manage CIA; comparable outcomes have been demonstrated between epoetin alfa 40,000 units once weekly and darbepoetin alfa 200 microg every two weeks. These commonly prescribed regimens necessitate extra clinic visits by cancer patients receiving cyclic chemotherapy. ESA administration can now often be synchronized with a three-week chemotherapy cycle because of the recent approval of darbepoetin alfa 500 microg every three weeks for CIA. However, in the Phase III trial providing the basis for this new dosage recommendation, more than 70% of patients required a 40% reduction in the dosage, resulting in an average dose of 375 microg every three weeks. The extended-dosage-interval regimens have not been associated with an increase in cardiovascular or thrombotic adverse events. Extended-dosage-interval regimens of epoetin alfa are under investigation and may provide additional alternatives. Synchronizing ESA therapy with scheduled chemotherapy visits would help minimize disruptions for patients and caregivers and improve the use of health care resources. CONCLUSION: Administration of darbepoetin alfa every three weeks offers the convenience of synchronization of treatment with 21-day-cycle chemotherapy in many patients with CIA. Extended-dosage-interval regimens for epoetin alfa are being investigated and show promise.     

Darbepoetin alfa.

Darbepoetin alfa is a novel erythropoiesis-stimulating protein developed for the treatment of anaemia associated with chronic kidney disease. In single-dose studies in patients undergoing dialysis, the mean terminal half-life for intravenous darbepoetin alfa was approximately 3-fold longer than for intravenous recombinant human erythropoitin (r-HuEPO, epoetin alfa; 25.3 vs 8.5 hours). The mean terminal half-life after subcutaneous administration of darbepoetin alfa was 48.8 hours. In randomised nonblind trials in patients undergoing dialysis, darbepoetin alfa (0.45 pg/kg) given once weekly for the correction of anaemia increased haemoglobin (Hb) levels to a similar extent as darbepoetin alfa three times weekly or r-HuEPO two or three times weekly. A double-blind, randomised clinical trial reported that switching patients from a three-times weekly regimen of r-HuEPO to once weekly darbepoetin alfa with additional placebo twice weekly (all intravenously) maintained Hb levels between 9.0 and 13.0 g/dl to a similar extent as continued treatment with r-HuEPO three times weekly. In a randomised nonblind study, r-HuEPO-naive patients with chronic renal insufficiency received either subcutaneous darbepoetin alfa once weekly or r-HuEPO twice weekly. 93% of patients receiving darbepoetin alfa and 92% of patients receiving r-HuEPO achieved a Hb increase of > or = 1.0 g/dl from baseline and the mean increase in Hb level over the initial 4 weeks was similar for both treatments. The number and frequency of adverse events, withdrawals and deaths reported in clinical trials did not differ between patients receiving darbepoetin alfa and patients receiving r-HuEPO. There have been no reports of immune responses to darbepoetin alfa in 1534 patients receiving treatment for up to 2 years.     

Darbepoetin alfa: in patients with chemotherapy-related anaemia

Darbepoetin alfa, novel erythropoiesis stimulating protein closely related to human erythropoietin, has been developed for the treatment of chemotherapy-related anaemia in patients with non-myeloid malignancies. In three 12-week, phase II studies in patients with cancer and chemotherapy-related anaemia, subcutaneous darbepoetin alfa, administered in once-weekly or 2-, 3- or 4-weekly regimens, dose-dependently increased the mean haemoglobin levels. In a randomised, double-blind, phase III study in 320 patients with lung cancer and chemotherapy-related anaemia, recipients of subcutaneous darbepoetin alfa 2.25 micro g/kg once weekly, received red blood cell (RBC) transfusion approximate, equals 2-fold less frequently than placebo recipients (p < 0.001). In the same study, patients receiving darbepoetin alfa also received fewer standard units of RBC for transfusion and had greater haematopoietic response rate than placebo recipients (both p < 0.001). Subcutaneous darbepoetin alfa 2.25 micro g/kg once weekly also reduced patient-reported fatigue (assessed by a quality-of-life questionnaire) [p = 0.019 vs placebo]. black triangle Darbepoetin alfa was generally well tolerated in clinical trials. The most frequent darbepoetin alfa-related adverse events were: body oedema, arthralgia and skin rash.     

Current and future options for the treatment of chemotherapy-induced anaemia

Chemotherapy-induced anaemia (CIA) is a significant source of morbidity in patients receiving treatment for cancer. There are three products currently available for the treatment of CIA: epoetin alfa, epoetin beta and darbepoetin alfa. Several organisations have published recommendations for the use of these agents. Several randomised, controlled trials have been conducted comparing the most popular dosing regimens of epoetin alfa and darbepoetin alfa, with conflicting results. Information regarding survival and adverse event data related to these agents continues to create debate. This review considers four new agents that are under development for the treatment of CIA.     

Current and future options for the treatment of chemotherapy-induced anaemia

Chemotherapy-induced anaemia (CIA) is a significant source of morbidity in patients receiving treatment for cancer. There are three products currently available for the treatment of CIA: epoetin alfa, epoetin beta and darbepoetin alfa. Several organisations have published recommendations for the use of these agents. Several randomised, controlled trials have been conducted comparing the most popular dosing regimens of epoetin alfa and darbepoetin alfa, with conflicting results. Information regarding survival and adverse event data related to these agents continues to create debate. This review considers four new agents that are under development for the treatment of CIA.     

Clinical and economic comparison of epoetin alfa and darbepoetin alfa

SUMMARY

Background: The pharmacoeconomics of erythropoietic therapy for the treatment of anemia is receiving renewed attention due to the current availability of two agents. Epoetin alfa has been the standard of therapy for patients with renal disease and cancer-related anemia for more than a decade. Darbepoetin alfa, an alternative agent, is now approved for anemia resulting from renal disease and cancer chemotherapy.

Methodology: Although direct comparative trials have not been performed with these agents, information published in the last several years regarding their clinical efficacy, safety, and dosing is sufficient, in most cases, to compare costs. With the disclaimer that any efficacy comparison of competing products using published reports has certain limitations, a cost-minimization approach from a provider's perspective was conducted.

Results:To provide background for the economic evaluation, pharmacokinetic and pharmacodynamic data for these two agents are discussed. Recent clinical trials in the nephrology and oncology therapeutic areas are summarized, highlighting study designs, dosing regimens, patient entry criteria, study endpoints, and published results. Cost data, based on average wholesale prices (AWP) in 2003, are compared and calculated from available clinical data with an emphasis on efficacy.

Conclusion: These evaluations largely conclude that epoetin alfa is the better pharmacoeconomic value of the two currently available erythropoietic agents.