A randomized, double-blind, placebo-controlled trial of recombinant erythropoietin in treatment of the anemia of bronchopulmonary dysplasia

Utilization of Erythropoietin within the United States Neonatal Intensive Care Units from 2008 to 2017

OBJECTIVE

Little data are available regarding erythropoietin (Epo) utilization patterns within neonatal intensive care units (NICUs). We sought to describe the trends in Epo utilization across a large cohort of U.S. NICUs.

STUDY DESIGN

This is a retrospective cohort study of infants discharged from 2008 to 2017 using the Pediatrix Clinical Data Warehouse.

RESULTS

We identified 704,159 eligible infants from 358 sites, of whom 9,749 (1.4%) had Epo exposure. For extremely low gestational age newborns (ELGANs), Epo exposure ranged from 7.6 to 13.5%. We found significant site variability in Epo utilization in ELGANs. Among the 299 NICUs caring for ELGANs during the study period, 184 (61.5%) never used Epo for this population, whereas 21 (7%) utilized Epo in 50% or more of eligible infants. Epo was initiated at a median of 25 days in ELGANs. For infants with hypoxic-ischemic encephalopathy (HIE), Epo exposure remained ≤1% through 2014 then increased fourfold to 3.4% by 2017. The median day of Epo initiation was the day of birth for infants diagnosed with HIE.

CONCLUSION

Epo is utilized in ELGANs more commonly than for other NICU populations. Utilization patterns appear to indicate the treatment of established anemia for ELGANs and more recently for neuroprotection in patients diagnosed with HIE.

Effects of a combined therapy of erythropoietin, iron, folate, and vitamin B12 on the transfusion requirements of extremely low birth weight infants

OBJECTIVES

Erythropoietin is frequently administered to premature infants to stimulate erythropoiesis. The primary goal of erythropoietin therapy is to reduce transfusions, but the efficacy of erythropoietin has not been convincingly demonstrated in this regard. The aim of this trial was to investigate whether combined administration of vitamin B12, folic acid, iron, and erythropoietin could decrease transfusion requirements in extremely low birth weight infants.

PATIENTS AND METHODS

In a randomized, controlled trial, extremely low birth weight infants with a birth weight < or = 800 g and a gestational age < or = 32 weeks were randomly assigned to a group receiving combination treatment or a control arm.

RESULTS

The treatment increased levels of folate in red blood cells, vitamin B12, ferritin, transferrin receptor levels in plasma, and reticulocyte counts. The proportion of infants requiring no transfusions was lower in the treatment group (38%) as compared with controls (5%). The treatment group and the need for mechanical ventilation were independent predictors of the number of transfusions in multiple regression analysis. Cox regression analysis indicated that combined therapy resulted in a 79% risk reduction for any transfusion.

CONCLUSION

Combined treatment with erythropoietin, intravenous iron, folate, and vitamin B12 during the first weeks reduces the need for transfusion in extremely low birth weight infants.

Effect of recombinant erythropoietin on "late" transfusions in the neonatal intensive care unit: a meta-analysis

OBJECTIVES

Using the approach of a meta-analysis, we sought to determine whether the administration of recombinant erythropoietin (rEpo) to very low birth weight (VLBW) infants, after the first week of life, results in fewer "late" transfusions.

STUDY DESIGN AND METHODS

The guidelines set forth by the Cochrane Neonatal Review Group were used to identify all relevant studies. Medline was searched from January 1990 to November of 2000. Studies that used a randomized, placebo-controlled, and double-masked design were deemed acceptable.

RESULTS

Eight studies meet the inclusion criteria. These involved 357 VLBW neonates: 183 rEpo and 174 placebo recipients. The neonates in the rEpo group received fewer erythrocyte transfusions during the study period than did those in the placebo group; the common odds ratio (OR)=0.33; 95% confidence interval (CI) 0.21-0.51. Furthermore, the rEpo effect size was a function of the dose of rEpo administered (p=0.0001).

CONCLUSION

A meta-analysis of the most scientifically rigorous studies on this topic indicates that administration of rEpo to VLBW infants reduces "late" erythrocyte transfusions in a dose-dependent manner.

The use of erythropoietin in neonates

Although much information has been accumulated about the clinical use of Epo in preterm infants, many questions remain unanswered. The evolution of clinical practice in the care of extremely ill, preterm infants continues to affect the number of transfusions required during hospitalization. Decreasing phlebotomy losses and instituting standardized transfusion guidelines have both been shown significantly to decrease the transfusion requirements of preterm infants. The administration of Epo likely decreases transfusion need even further; however, the direct impact of each of these actions has not been studied prospectively. It is likely that the combination of instituting rigorous and standardized transfusion guidelines, decreasing phlebotomy losses, and the appropriate use of Epo will have the greatest impact in decreasing transfusion requirements in all preterm and term neonates, regardless of the cause of their anemia.

Increased hematocrit and decreased transfusion requirements in children given erythropoietin before undergoing craniofacial surgery

OBJECT

This study was undertaken to determine the efficacy of preoperative erythropoietin administration in infants scheduled for craniofacial surgery and, in so doing, to minimize problems associated with blood transfusions.

METHODS

Families were offered the option of having their children receive erythropoietin injections before undergoing craniofacial surgery. The children whose families accepted this option received daily iron and 300 U/kg erythropoietin three times per week for 3 weeks preoperatively. Weekly complete blood counts with reticulocyte counts were measured and transfusion requirements were noted. Blood transfusions were administered depending on the clinical condition of the child. A case-matched control population was also evaluated to compare initial hematocrit levels and transfusion requirements. Thirty patients in the erythropoietin treatment group and 30 control patients were evaluated. The dose of erythropoietin administered was shown to increase hematocrit levels from 35.4 +/- 0.9% to 43.3 +/- 0.9% during the course of therapy. The resulting hematocrit levels in patients treated with erythropoietin at the time of surgery were higher compared with baseline hematocrit levels obtained in control patients at the time of surgery (34.2 +/- 0.5%). Transfusion requirements also differed: all control patients received transfusions, whereas 64% (19 of 30) of erythropoietin-treated patients received transfusions.

CONCLUSIONS

The authors conclude that treatment with erythropoietin in otherwise healthy young children will increase hematocrit levels and modify transfusion requirements. Erythropoietin therapy for elective surgery in children of this age must be individualized according to the clinical situation, family and physician beliefs, and cost effectiveness, as evaluated at the individual center.

The effect of erythropoietin on the transfusion requirements of preterm infants weighing 750 grams or less: a randomized, double-blind, placebo-controlled study

BACKGROUND

Clinical trials of erythropoietin (EPO) administration to preterm infants have not focused on infants weighing 750 gm or less, the population most likely to receive multiple transfusions because of large phlebotomy losses. It is unknown whether preterm infants weighing 750 gm or less will respond to EPO by accelerating erythropoiesis, or whether EPO administered to this population will decrease blood transfusions.

METHODS

We randomly assigned 28 extremely low birth weight preterm infants (mean +/- SEM: 24.7 +/- 0.3 weeks' gestation, 662 +/- 14 gm birth weight), in the first 72 hours of life, to receive either EPO (200 U/kg/day) or placebo for 14 days and administered transfusions only according to protocol over a 21-day study period. All infants received 1 mg/kg/day iron dextran in their total parenteral nutrition solution during the 14-day treatment period.

RESULTS

During the 21-day study period, a lower number and volume of transfusions were received by the EPO recipients (4.7 +/- 0.7 transfusions per patient and 70 +/- 11 ml/kg per patient) than by the placebo recipients (7.5 +/- 1.1 transfusions per patient and 112 +/- 17 ml/kg per patient; p < 0.05, EPO vs placebo), whereas hematocrits remained similar in the two groups. Reticulocyte counts were similar in both groups on day 1 but were greater in the EPO recipients on day 14 (EPO day 1, 351 +/- 53; EPO day 14, 359 +/- 40 x 10(3)/microl; placebo day 1, 334 +/- 64; placebo day 14, 120 +/- 10 x 10(3)/microl; p < 0.01, EPO vs placebo). Serum ferritin concentrations were similar in both groups at the beginning of the study but were greater in the placebo recipients by day 14 (EPO, 262 +/- 44 microg/L; placebo, 593 +/- 92 microg/L; p < 0.01). No adverse effects of EPO or iron were noted.

CONCLUSION

The combination of EPO and parenteral iron stimulates erythropoiesis in preterm infants weighing 750 gm or less and results in fewer transfusions during their first 3 weeks of life.

Use of Hematopoietic Growth Factors in the Neonatal Intensive Care Unit

Recombinant hematopoietic growth factors have emerged as valuable treatments for a variety of medical conditions. Recently, their applications have reached the neonatal intensive care unit, where they offer new therapeutic options for problems as common as anemia of prematurity, or as catastrophic as neonatal sepsis. When facing bacterial infection, it is known that newborn infants are capable of increasing their serum G-CSF concentrations. However, their response does not reach the concentrations that adults are able to achieve, and frequently neutropenia complicates the picture of neonatal sepsis. Although Phase III clinical trials are still in progress, published animal studies, case reports, and Phase I trials suggest that neonates with a variety of neutropenias experience a rapid elevation in their blood neutrophil concentration following administration of rG-CSF, without significant adverse effects. Although many factors contribute to the development of the “anemia of prematurity,” one of the major factors is the inability of preterm infants to generate an erythropoietin (Epo) response appropriate to their degree of anemia. On the basis of this fact, administration of rEpo to preterm neonates to treat or to prevent the anemia of prematurity has been the subject of multiple clinical studies, and it is now clear that rEpo administration to this population can indeed result in lower transfusion requirements, with only occasional and mild adverse effects. Neonatal thrombocytopenia is also a frequent clinical problem, which in most patients develops without a clear underlying cause. Recent studies, quantifying circulating megakaryocyte progenitors in the peripheral blood of thrombocytopenic neonates, suggest that impaired megakaryocytopoiesis may be the main underlying mechanism of many cases of thrombocytopenia. On the basis of this finding, it is tempting to speculate that recombinant thrombopoietin, the newly discovered physiological stimulator of platelet production, will be of clinical relevance in the treatment of thrombocytopenic neonates.

Randomised controlled double blind study of role of recombinant erythropoietin in the prevention of chronic lung disease

AIM

To evaluate the role of recombinant human erythropoietin (R-HuEpo) in reducing iron infusion, which may exacerbate free radical damage, leading to chronic lung disease.

METHODS

A multicentre, randomised, placebo controlled, double blind study was carried out in four neonatal intensive care units in Yorkshire. Infants were randomly allocated and received either R-HuEpo (480 U/kg/wk) or placebo by twice weekly subcutaneous injection. The primary outcome measure was the number of days on respiratory support and a secondary outcome the number of blood transfusions required.

RESULTS

Forty two very low birthweight (VLBW) infants were randomly allocated. There was little difference in the need for respiratory support one month after randomisation, but subsequently there was a trend towards a reduction in the proportion requiring respiratory support in the R-HuEpo group (difference at three months -0.50, 95% confidence interval -1.00, 0.17). During stay in hospital, the median number of blood transfusions was lower for infants in the R-HuEpo group (difference in medians -2, 95% CI -4, 0). The study was stopped early because of failure to recruit babies at the expected rate.

CONCLUSIONS

R-HuEpo seems to reduce the number of days in oxygen for ill VLBW infants. These data could be used to construct a larger multicentre study to evaluate this effect further.

The role of erythropoietin in the anemia of prematurity

Neonatal erythropoiesis is limited by a relatively inadequate production of erythropoietin. This is likely the result of dependence on the hepatic production of erythropoietin and an incomplete switchover to renal production. The present model of neonatal erythropoiesis suggests that the use of exogenous erythropoietin should correct the early anemia of prematurity that is observed at 6 weeks of age in premature newborns. Randomized, controlled trials of erythropoietin use in very low birthweight infants are reviewed. The data support the conclusion that erythropoietin at doses of > or = 750 u/kg/wk started at less than 7 days of age results in improved reticulocyte counts and hemoglobin levels, but does not reduce the number of infants who will be exposed to blood products. Erythropoietin at doses of > or = 600 u/kg/wk started at an average of 21 days of life improves reticulocyte counts and hemoglobin levels, and reduces the number of infants will will require late transfusion, but does nothing for the bulk of infants who are transfused before that age.

Erythropoietin receptors are expressed in the central nervous system of mid-trimester human fetuses

Recombinant erythropoietin (rEpo) is an effective treatment for infants with the anemia of prematurity. rEpo was previously thought to act only on erythroid progenitor cells, but evidence now indicates that certain nonerythroid cells also express functional erythropoietin receptors (Epo-R). Such receptors have been observed on cells in the developing murine brain and spinal cord. The objective of this study was to determine whether Epo-R are expressed in the CNS of mid-trimester human fetuses. For this study, spinal cords were collected from five mid-trimester abortuses. RNA was extracted from the washed specimens, and the presence of Epo-R mRNA was sought by reverse transcription followed by polymerase chain reaction. Immunohistochemistry was then used to determine the anatomic location of the cells expressing Epo-R within the fetal spinal cord. The results showed that all fetal spinal cords tested contained Epo-R mRNA. The cells expressing Epo-R were radiating from the ependymal canal toward the anterior and posterior median sulci. We conclude that Epo-R are expressed on cells in the developing human CNS. Further studies are needed to determine whether they are clinically relevant in the premature infant.

Erythropoietin therapy in neonates at risk of having bronchopulmonary dysplasia and requiring multiple transfusions

OBJECTIVES

To determine whether treatment with recombinant human erythropoietin (r-HuEPO) reduces transfusion requirements in premature neonates at risk of having bronchopulmonary dysplasia and requiring multiple transfusions.

STUDY DESIGN

A double-blind, randomized, controlled trial.

SUBJECTS

Fifty-five infants appropriate in weight for gestational age (less than 1250 gm birth weight) who, at 10 days of age, were predicted to have a greater than 75% probability of having bronchopulmonary dysplasia. This criterion had previously been shown to identify infants requiring multiple transfusions. Twenty-seven infants were randomly assigned to receive r-HuEPO therapy and 28 to a control group. r-HuEPO was administered in a dosage of 20 U/kg body weight, subcutaneously, three times a week for 6 weeks. Control infants received sham treatment.

RESULTS

Infants treated with r-HuEPO required significantly fewer transfusions than control infants during their entire hospital stay (mean 3.48 +/- 1.58 vs 5.68 +/- 2.30; p = 0.0001) and had a higher mean reticulocyte count (p < or = 0.0005) and a higher mean hemoglobin concentration (p < or = 0.005) during the treatment period. At follow-up, 4 months after term, there were no significant differences between the groups in mean reticulocyte count (p = 0.86) or mean hemoglobin concentration (p = 0.56). However, two infants in each group had low serum ferritin values indicative of depleted iron stores.

CONCLUSIONS

Treatment with r-HuEPO effectively stimulated erythropoiesis in premature infants at high risk of having bronchopulmonary dysplasia and requiring multiple transfusions; the result was a reduction in transfusion requirements. This treatment, together with other strategies to reduce the need for transfusions, is appropriate in this population. Unrelated to r-HuEPO treatment, these infants may be at risk of having iron deficiency later in infancy.

Efficacy and cost analysis of treating very low birth weight infants with erythropoietin during their first two weeks of life: a randomized, placebo-controlled trial

OBJECTIVE

We hypothesized that using a higher dose of erythropoietin (Epo) and starting treatment on the first day of life would reduce the transfusion requirements of ventilator-dependent and non-ventilator-dependent very low birth weight (VLBW) infants. Moreover, we hypothesized that this treatment would be cost-effective.

METHODS

We randomly assigned 20 ill newborn VLBW infants to receive either Epo (200 units/kg per day) or placebo during their first 2 weeks of life. The caregivers were unaware of the treatment assignments, and erythrocyte transfusions were administered according to hematocrit and signs of anemia.

RESULTS

On day 1, reticulocyte counts and hematocrits were similar in the two groups. During the subsequent 2 weeks, reticulocyte counts of the placebo recipients fell significantly below those of the Epo recipients, but hematocrits in the two groups did not differ. More transfusions were received by the placebo recipients (mean = 1.4 per patient) than by the Epo recipients (mean = 0.2 per patient; p < 0.01). No adverse effects of Epo were noted, and the costs in the placebo group exceeded those in the Epo group.

CONCLUSIONS

We conclude that administration of Epo to VLBW infants during the first 2 weeks of life results in fewer transfusions and is cost-effective.

Use of erythropoietin in premature neonates: controversies and the future

OBJECTIVE

To review and evaluate current research on the use of recombinant human erythropoietin (rhEPO) for the treatment of anemia of prematurity (AOP).

DATA SOURCES

A MEDLINE search (1985-September 1994) was used to identify and retrieve pertinent data about erythropoietin's use in premature neonates. Bibliographies in the relevant literature and International Pharmacy Abstracts were reviewed as well.

STUDY SELECTION

The authors extrapolated data from trials and other literature in which the entire paper or abstract was published. Because of the paucity of data on the use of rhEPO in neonates, all available literature was reviewed and cited, regardless of study methodology.

DATA SYNTHESIS

Most data support that rhEPO is efficacious in treating AOP. Until recently, the published investigations have included only small numbers of patients. Larger, multicenter, placebo-controlled trials suggest that infants weighing less than 1500 g benefit from rhEPO therapy. Questions remain concerning the rhEPO dose and nutrient requirements for optimal efficacy.

CONCLUSIONS

Published clinical trials that have examined the efficacy of rhEPO in the treatment of AOP vary considerably with regard to methodology, rhEPO dose, nutrient doses, and outcome measurement. At present, many questions remain to be answered including ascertaining rhEPO's long-term benefit versus cost/risk as well as its potential contribution to improving the care of the premature neonate.

Neonatal anemia: pathophysiology and treatment

All neonates experience a decline in circulating red blood cell (RBC) mass due to diminished erythropoietin (EPO) levels. This effect is more pronounced in small, premature infants and can lead to severe anemia and need for RBC transfusions--particularly, if repeated phlebotomy is required to monitor acutely-ill neonates. Although optimal RBC transfusion therapy has been a long-term challenge for neonatologists, the emergence of recombinant EPO as promising therapy for neonatal anemia is the major issue for 1994. Accordingly, this report for the 12th International Convocation on Immunology (Transfusion Immunology and Medicine) will focus on this aspect of neonatal transfusion medicine. Although several controlled trials to evaluate EPO as therapy have been completed, definitive answers to all questions regarding efficacy and possible toxicity have not been provided. However, therapy with EPO plus iron and adequate nutrition is likely to be proven effective for the relatively late anemia of stable prematures. To date, EPO has not been shown, convincingly, to alleviate the anemia present early in the life of acutely-ill, premature infants.

Prospective, randomized trial of the safety and efficacy of a limited donor exposure transfusion program for premature neonates

We investigated the safety and efficacy of using a single unit of packed red blood cells until its expiration date (35 days) to meet the transfusion needs of infants weighting < 1.5 kg. Unit concentration of potassium and infants' hematocrit value, K+ level, pH, and base excess were measured before and after transfusion. Compared with control infants, study infants had similar transfusion needs, but received blood from significantly fewer donors. The age of the blood received by study infants was significantly older and had a higher plasma K+ level. However, the change in infants' serum K+ levels before and after a transfusion was not significantly different in the two groups, and no adverse effects from transfusion of older blood were observed. We conclude that a protocol that allows use of an assigned unit of packed red blood cells preserved with citrate-phosphate-dextrose-adenine anticoagulant until its expiration date is safe, minimizes donor exposures, and meets the transfusion needs of low birth weight neonates.