Hereditary angioedema outcomes in US patients switched from injectable long-term prophylactic medication to oral berotralstat

BACKGROUND

Berotralstat, a first-line, once-daily, oral plasma kallikrein inhibitor for long-term prophylaxis of hereditary angioedema (HAE), is an effective and well-tolerated treatment option.

OBJECTIVE

To summarize the safety, effectiveness, and impact on treatment satisfaction in patients who switched from injectable long-term prophylactics to oral berotralstat monotherapy (150 mg daily) at US sites in the international open-label APeX-S study.

METHODS

APeX-S was an open-label, Phase II study of berotralstat conducted in 22 countries. Here, we focus on APeX-S patients enrolled at US sites who switched from injectable long-term prophylactics to berotralstat 150 mg once-daily monotherapy.

RESULTS

A total of 34 patients discontinued lanadelumab (n = 21), subcutaneous C1 esterase inhibitor (n = 11), or intravenous C1 esterase inhibitor (n = 2) and switched to berotralstat 150 mg monotherapy. Vomiting, diarrhea, and upper respiratory tract infection were the most common adverse events (each 11.8%). Mean monthly attack rates were consistently low after the switch to berotralstat. The mean (SEM) monthly attack rate was 0.29 (0.11) at Month 1, 0.48 (0.15) at Month 6, and 0.58 (0.23) at Month 12. The median attack rate was 0 attack/mo throughout 12 months of treatment. Improvements were observed in the Treatment Satisfaction Questionnaire for Medication from baseline to Month 12 after the switch to berotralstat monotherapy, with the greatest improvements in convenience.

CONCLUSION

The transition from injectable prophylactic medication to berotralstat was generally well tolerated. Patients switching to berotralstat monotherapy maintained good control of their HAE symptoms and reported improved treatment satisfaction.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03472040.

Once-Daily Oral Berotralstat for Long-Term Prophylaxis of Hereditary Angioedema: The Open-Label Extension of the APeX-2 Randomized Trial

BACKGROUND

Berotralstat is a first-line, once-daily oral plasma kallikrein inhibitor approved for prophylaxis of hereditary angioedema (HAE) attacks in patients 12 years or older.

OBJECTIVE

This analysis examined the safety and effectiveness of long-term prophylaxis with berotralstat.

METHODS

APeX-2 was a phase 3, parallel-group, multicenter trial in patients with HAE caused by C1-inhibitor deficiency (NCT03485911). Part 1 was a randomized, double-blind, placebo-controlled evaluation of 150 and 110 mg of berotralstat over 24 weeks. In part 2, berotralstat-treated patients continued the same treatment, and placebo-treated patients were re-randomized to 150 or 110 mg of berotralstat for 24 weeks. In part 3, all patients were treated with open-label berotralstat at 150 mg, which could be continued for up to an additional 4 years. In part 3, the primary endpoint was long-term safety and tolerability. Secondary endpoints included HAE attack rates and quality of life (QoL).

RESULTS

Eighty-one patients entered part 3. Treatment-emergent adverse events (TEAEs) occurred in 82.7% of patients, with most being mild or moderate in severity. The most common TEAEs were nasopharyngitis, urinary tract infection, abdominal pain, arthralgia, coronavirus infection, and diarrhea. Drug-related TEAEs occurred in 14.8% of patients, but none were serious. For patients who completed 96 weeks of berotralstat treatment (n = 70), the mean (standard error) change in attack rate from baseline was -2.21 (0.20) attacks/mo. Clinically meaningful improvements in QoL were also observed, with the largest improvements in the functioning domain.

CONCLUSION

Berotralstat was generally well tolerated, provided rapid and sustained reductions in HAE attacks and improved QoL over 96 weeks.

Berotralstat for long-term prophylaxis of hereditary angioedema in Japan: Parts 2 and 3 of the randomized APeX-J Phase III trial

Background

Berotralstat is a once-daily oral inhibitor of plasma kallikrein for the prophylaxis of hereditary angioedema (HAE) in patients ≥12 years. APeX-J aimed to evaluate the efficacy and safety of berotralstat in Japan.

Methods

APeX-J was a Phase III trial comprising 3 parts (NCT03873116). Part 1 was a randomized, placebo-controlled evaluation of berotralstat 150 or 110 mg over 24 weeks. Part 2 was a 28-week dose-blinded phase in which berotralstat-treated patients continued the same dose and placebo patients were re-randomized to berotralstat 150 or 110 mg. In Part 3, all patients remaining on study received berotralstat 150 mg in an open-label manner for up to an additional 52 weeks. The primary endpoint of Parts 2 and 3 was long-term safety and tolerability, and secondary endpoints examined effectiveness.

Results

Seventeen patients entered Part 2, and 11 continued into Part 3. Treatment-emergent adverse events (TEAEs) were reported by 14/17 patients (82.4%) in Parts 2 or 3; the most common were nasopharyngitis, abdominal pain, cystitis, influenza, and vertigo. One patient (5.9%) experienced a drug-related TEAE (Grade 4 increased hepatic enzyme). No drug-related serious TEAEs were reported. For patients who completed 26 months of treatment with berotralstat 150 mg (n = 5), mean (standard error of the mean) monthly HAE attack rates and on-demand medication use decreased from baseline by 1.15 (0.09) attacks/month and 2.8 (0.64) doses/month, respectively. Sustained improvements were also observed in patient quality of life and treatment satisfaction.

Conclusions

Long-term prophylaxis with berotralstat raised no new safety signals and was effective at reducing attacks and improving patient-reported outcomes.

Trial registration

ClinicalTrials.gov NCT03873116. Registered March 13, 2019. Retrospectively registered.

Assessment of HAE prophylaxis transition from androgen therapy to berotralstat: A subset analysis of the APeX-S trial

Background

Given the recent approval of oral berotralstat in several countries for hereditary angioedema (HAE) prophylaxis, transition from long-term androgens to berotralstat may occur in clinical practice. The open-label, Phase II APeX-S trial provided an opportunity to assess the safety and effectiveness of berotralstat in patients previously treated with differing durations of androgens and shorter transition periods. Therefore, we examined the safety, effectiveness, and impact on quality of life of berotralstat after prior androgen use in patients from the APeX-S trial. Alanine aminotransferase (ALT) elevations were also examined because of the association with androgen exposure and hepatic function impairment.

Methods

We conducted an analysis of a subset of 39 patients from the APeX-S trial aged ≥12 years with HAE due to C1 inhibitor deficiency (HAE-C1-INH) with prior androgen use who discontinued androgen therapy within <60 days of receiving berotralstat. Patients received daily berotralstat (150 mg) and were divided into subgroups for this analysis based on time between androgen discontinuation and berotralstat commencement (<14 days versus 14 to <60 days).

Results

Berotralstat was generally well tolerated, with nasopharyngitis (21%), upper respiratory tract infection (15%), nausea (15%), diarrhea (15%), and abdominal pain (10%) being the most common adverse events occurring in ≥10% of the total subset. Only 7/145 (5%) of all APeX-S study patients with a prior history of androgen therapy experienced ALT elevations, 6 of which were grade 3 or 4 toxicities. All 7 patients recovered without sequelae and belonged to the subgroup of patients who transitioned <14 days after discontinuing androgens (n = 18). A reduction in monthly attack rate versus Month 1 was observed over 12 months for all patients who transitioned from prior androgen therapy to berotralstat prophylaxis in under 60 days, irrespective of duration of prior androgen therapy or timing of transition (N = 39). Similarly, meaningful patient-reported improvements from both Angioedema Quality of Life Questionnaire and Treatment Satisfaction Questionnaire for Medication scores were achieved, with a sustained benefit shown over the berotralstat treatment period.

Conclusions

Berotralstat treatment led to sustained HAE symptom control irrespective of duration of prior androgen therapy or timing of transition. Most patients safely transitioned from long-term androgens to berotralstat. Although occurring in a small group of patients, liver-related adverse events following berotralstat treatment may be associated with a shorter androgen washout period, but further research is required to confirm this.

Clinical trial registration

NCT03472040. Retrospectively registered March 21, 2018.

Erythropoiesis stimulating agents and reno-protection: a meta-analysis

Background

Erythropoiesis stimulating agents (ESAs) were proposed to enhance survival of renal tissues through direct effects via activation of EPO receptors on renal cells resulting in reduced cell apoptosis, or indirect effects via increased oxygen delivery due to increased numbers of Hb containing red blood cells. Thus through several mechanisms there may be benefit of ESA administration on kidney disease progression and kidney function in renal patients. However conflicting ESA reno-protection outcomes have been reported in both pre-clinical animal studies and human clinical trials. To better understand the potential beneficial effects of ESAs on renal-patients, meta-analyses of clinical trials is needed.

Methods

Literature searches and manual searches of references lists from published studies were performed. Controlled trials that included ESA treatment on renal patients with relevant renal endpoints were selected.

Results

Thirty two ESA controlled trials in 3 categories of intervention were identified. These included 7 trials with patients who had a high likelihood of AKI, 7 trials with kidney transplant patients and 18 anemia correction trials with chronic kidney disease (predialysis) patients. There was a trend toward improvement in renal outcomes in the ESA treated arm of AKI and transplant trials, but none reached statistical significance. In 12 of the anemia correction trials, meta-analyses showed no difference in renal outcomes with the anemia correction but both arms received some ESA treatment making it difficult to assess effects of ESA treatment alone. However, in 6 trials the low Hb arm received no ESAs and meta-analysis also showed no difference in renal outcomes, consistent with no benefit of ESA/ Hb increase.

Conclusions

Most ESA trials were small with modest event rates. While trends tended to favor the ESA treatment arm, these meta-analyses showed no reduction of incidence of AKI, no reduction in DGF or improvement in 1-year graft survival after renal transplantation and no significant delay in progression of CKD. These results do not support significant clinical reno-protection by ESAs.

Efficacy and safety of darbepoetin alpha in patients with myelodysplastic syndromes: a systematic review and meta-analysis

We conducted a systematic review and meta‐analysis to estimate the efficacy of darbepoetin alpha (DA) for treatment of myelodysplastic syndrome (MDS)‐related anaemia. Eligible studies were prospective, interventional, and reported World Health Organization, French‐American‐British, or International Prognostic Scoring System (IPSS) criteria. Outcomes included erythroid response rate (primary); haemoglobin response; change in haemoglobin, transfusion status, and quality‐of‐life (QoL); and safety. Ten studies (N = 647) were analysed. Erythroid response rate range was 38–72%; median response duration range was 12–51+ months. Patients with erythropoietin (EPO) <100 iu/l had 35% [95% confidence interval (CI): 22–48%; P < 0·001) better response than patients with EPO >100 iu/l. Erythropoesis‐stimulating agent (ESA)‐naïve patients had 17% (95% CI: 3–32%; P = 0·022) greater response rate than those previously treated with ESA. Nonetheless, previously treated patients had response rates of 25–75%. Higher baseline haemoglobin levels, higher dose, transfusion‐independence and low‐risk IPSS status were reported by several studies to be associated with better response. QoL, transfusion rates and haemoglobin levels improved with treatment. Hypertension, thromboembolism and progression to acute myeloid leukaemia were reported in 2%, 1% and 1% of patients, respectively. This meta‐analysis suggests that DA treatment can be useful for improving erythroid response in MDS patients with anaemia, even among patients previously treated with ESA.

Changing patterns of chemotherapy relative dose intensity and supportive care for aggressive B-cell non-Hodgkin lymphoma

Maintaining high relative dose intensity (RDI) is associated with improved outcomes, especially in patients with aggressive B-cell non-Hodgkin lymphoma (NHL). To evaluate changes in practice, we examined RDI, chemotherapy treatment patterns, dose delays and reductions, neutropenia and related consequences, and supportive care in 500 patients with aggressive B-cell NHL treated between 2006-2009. We then compared the results to a previous study of patients treated between 1993-2001. Relative to the previous study, rituximab was a common addition to CHOP-21 (91% vs. 3%), more patients received an RDI ≥ 85% (68% vs. 52%), and fewer patients experienced dose reductions (21% vs. 35%), though incidences of dose delays were similar (26% vs. 23%). Incidences of febrile neutropenia (FN; 12% vs. 21%) and FN-related hospitalizations (10% vs. 16%) were lower. Finally, more patients received primary prophylaxis with colony-stimulating factors (75% vs. 12%). Together, these results illustrate evolving practice patterns for patients with aggressive B-cell NHL.

Survival effects of erythropoiesis-stimulating agents (ESAs) in patients with breast cancer: A meta-analysis

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Background: New data are available from two trials of ESA use in patients with breast cancer receiving chemotherapy. We conducted a meta-analysis of trials of ESA use in this population. Methods: A literature search identified reports from 1997-2012 that included mortality data from controlled ESA trials (epoetin alfa, epoetin beta, darbepoetin alfa, biosimilars) in patients with breast cancer receiving chemotherapy. We used data from company databases for Amgen Inc. or Janssen Products LP studies and published data for other studies. Random-effects odds ratios (OR) were calculated to compare results for patients randomized to ESA to patients randomized to control. Analyses were stratified by metastatic stage; mixed stage or treatment; and adjuvant/neoadjuvant treatment. Results: We analyzed 9 studies (N = 4,713; ESA n = 2,346, control n = 2367) (Table).The overall stratified random-effects OR for death was 1.17 (95% confidence interval, 0.99-1.39). Details are presented in the Table. Conclusions: Overall survival OR remains consistent with prior data after including recent results. [Table: see text]

Survival effects of erythropoiesis-stimulating agents (ESAs) in patients with breast cancer: A meta-analysis

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Background: New data are available from two trials of ESA use in patients with breast cancer receiving chemotherapy. We conducted a meta-analysis of trials of ESA use in this population. Methods: A literature search identified reports from 1997-2012 that included mortality data from controlled ESA trials (epoetin alfa, epoetin beta, darbepoetin alfa, biosimilars) in patients with breast cancer receiving chemotherapy. We used data from company databases for Amgen Inc. or Janssen Products LP studies and published data for other studies. Random-effects odds ratios (OR) were calculated to compare results for patients randomized to ESA to patients randomized to control. Analyses were stratified by metastatic stage; mixed stage or treatment; and adjuvant/neoadjuvant treatment. Results: We analyzed 9 studies (N = 4713; ESA n = 2346, control n = 2367) (Table).The overall stratified random-effects OR for death was 1.17 (95% confidence interval, 0.99-1.39). Details are presented in the Table. Conclusions: Overall survival OR remains consistent with prior data after including recent results. [Table: see text]

Effects of erythropoiesis-stimulating agents on survival and other outcomes in patients with lymphoproliferative malignancies: a study-level meta-analysis

Erythropoiesis-stimulating agents (ESAs) are approved to treat anemia in patients with non-myeloid malignancies receiving myelosuppressive chemotherapy. ESAs reduce transfusion rates, but some clinical studies suggest that ESAs may reduce survival or increase disease progression. This study-level meta-analysis examined the effects of darbepoetin alfa, epoetin alfa or epoetin beta on mortality, disease progression and transfusion incidence in patients with lymphoproliferative malignancies, using randomized, controlled trials of patients receiving chemotherapy and ESAs or standard of care. The odds ratio (OR) for mortality was 1.04 (95% confidence interval [CI], 0.81-1.34, random-effects model, 10 studies); the risk difference was - 0.01 (95% CI, - 0.03-0.02). The OR for disease progression was 1.02 (95% CI 0.81-1.30, random-effects model, five studies). A lower proportion of ESA-treated patients than controls received transfusions (seven studies). In this meta-analysis, ESAs reduced transfusions with no clear effect on mortality or disease progression in patients with lymphoproliferative malignancies receiving chemotherapy.

Current patterns of chemotherapy and supportive care for early-stage breast cancer (ESBC)

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Background: ESBC is commonly treated with myelosuppressive chemotherapy, and high relative dose intensity (RDI) correlates with improved overall survival. A retrospective analysis of patients with ESBC treated from 1997–2000 showed that 56% received an RDI < 85% (Lyman et al. JCO. 2003;21:4524-4531). To determine current practice, we evaluated ESBC treatment patterns at 24 US community- and hospital-based oncology practices. Methods: Data were abstracted from medical records of 532 patients with ESBC treated from January 2007–December 2009. Inclusion criteria included surgically resected ESBC (stage I-IIIA); ≥ 18 years old; and completion of at least 1 standard chemotherapy cycle on an every 2 or 3 week schedule. The primary endpoint was RDI over planned cycles. Other endpoints were incidence of dose delays ≥ 7 days, dose reductions ≥ 15% from standard, grade 3/4 neutropenia (SN), febrile neutropenia (FN), FN-related hospitalization, granulocyte-colony stimulating factor (G-CSF) use, and antimicrobial therapy. Descriptive statistics were generated for all endpoints. Results: In this study, mean (range) age was 55 (29–85) years. Relative to previously published results, chemotherapy regimens have shifted from mainly doxorubicin + cyclophosphamide (AC) (previously 35%) to docetaxel + cyclophosphamide (TC; n = 221; 42%) and AC followed by paclitaxel (AC-T; n = 163; 31%). Mean RDI is now higher (93% for both TC and the most common AC-T schedule [dose dense AC-T; n = 84] vs 79% previously); the incidence of dose delays (16% vs 25% previously) and dose reductions (21% vs 37% previously) have decreased; and primary prophylactic use of G-CSF has increased (76% vs 3% previously). In this study, 40% of patients had SN, 3% had FN, 2% had an FN-related hospitalization, and 30% received antimicrobial therapy. These measures were not available in the previously published results. Conclusions: The observed changes between the two studies are noteworthy though inferential comparisons are limited by changes in treatments and other factors. RDI has improved over time, but 16% of patients in this study received an RDI < 85%. Further evaluation is needed to identify factors associated with lower RDI and determine outcomes for these patients.

Meta-analysis of the effects on safety of front-loading (FL), every-2-week (Q2W), and Q3W dosing of darbepoetin alfa (DA) in patients (pts) with chemotherapy-induced anemia (CIA)

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Background: Several studies evaluated if alternate dosing could decrease the time to hemoglobin (Hb) response. With recent safety concerns, this is now of limited interest; however, these studies may contribute to the understanding of safety risks. This study-level meta-analysis examined effects of FL, Q2W, and Q3W dosing of DA vs epoetin alfa (EA) and weekly DA dosing on safety in pts with CIA. Methods: Data from 11 studies (4 FL, 5 Q2W, 1 Q3W, 1 Q2W/Q3W) conducted between 1999 and 2006 in which the comparison group received 3-times-per-week (TIW) or once-weekly (QW) EA or QW DA were included in the meta-analysis. FL dosing differed between the studies and was defined as DA 4.5 mcg/kg or 300 mg QW for 4 or 5 weeks or until Hb > 12 g/dL followed by either DA 4.5 mcg/kg Q3W or a lower QW dose. Endpoints included deaths on study; disease progression (PD); embolic, thrombotic, and thromboembolic events; and rapid Hb rise (1 g/dL within 14 days). Random effects odds ratios (ORs) are provided comparing FL, Q2W, or Q3W arms to either TIW or QW active control arms. Heterogeneity was assessed using I2 statistic. Results: No differences in ORs for death, PD, embolic, thrombotic, and thromboembolic events or evidence of a more rapid rate of Hb rise were observed in FL, Q2W, and Q3W arms compared with controls (table). Conclusions: Results of this meta-analysis suggested that these adverse events were not related to FL, Q2W, or Q3W dosing of DA. [Table: see text]

Assessing the effect of darbepoetin alfa on patient-reported fatigue in chemotherapy-induced anemia in four randomized, placebo-controlled clinical trials

PURPOSE

This analysis examined the effects of darbepoetin alfa on hemoglobin and fatigue outcomes in patients with cancer using latent growth curve modeling (LGM).

METHODS

Data from 4 clinical trials of darbepoetin alfa in lung cancer (2 studies; n = 547; n = 288), lymphoproliferative malignancies (n = 339), and non-myeloid malignancies (n = 320) were analyzed separately. Fatigue was assessed using the FACT-Fatigue (FACT-F) scale. Effects of darbepoetin alfa on changes in hemoglobin and FACT-F scores were evaluated using LGM, controlling for age, gender, Eastern Cooperative Oncology Group performance status, health status, and total transfusions.

RESULTS

Patients receiving darbepoetin alfa had higher rates of change in hemoglobin (standardized regression coefficient [[Formula: see text]] = 0.30 to 0.53, all P < 0.05) than placebo. Patients with greater rates of change in hemoglobin reported improvements in fatigue outcomes ([Formula: see text] = 0.28 to 0.59, all P < 0.05). The total standardized effect of darbepoetin alfa on fatigue outcomes corresponded to a mean change of 0.9 to 3.5 points in FACT-F scores, with one trial demonstrating changes exceeding the minimal important difference of 3 points.

CONCLUSIONS

Darbepoetin alfa improved hemoglobin which was associated with improved fatigue across the 4 trials. Clinically, meaningful improvement in fatigue was seen in 2 trials. More complex statistical analysis models of treatment may assist in understanding the effects of erythropoiesis-stimulating agents on patient-reported outcomes.

Erythropoiesis-stimulating agents in oncology: a study-level meta-analysis of survival and other safety outcomes

BACKGROUND: Cancer patients often develop the potentially debilitating condition of anaemia. Numerous controlled studies indicate that erythropoiesis-stimulating agents (ESAs) can raise haemoglobin levels and reduce transfusion requirements in anaemic cancer patients receiving chemotherapy. To evaluate recent safety concerns regarding ESAs, we carried out a meta-analysis of controlled ESA oncology trials to examine whether ESA use affects survival, disease progression and risk of venous-thromboembolic events.

METHODS: This meta-analysis included studies from the 2006 Cochrane meta-analysis, studies published/updated since the 2006 Cochrane report, and unpublished trial data from Amgen and Centocor Ortho Biotech. The 60 studies analysed (15 323 patients) were conducted in the settings of chemotherapy/radiochemotherapy, radiotherapy only treatment or anaemia of cancer. Data were summarised using odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS: Results indicated that ESA use did not significantly affect mortality (60 studies: OR=1.06; 95% CI: 0.97–1.15) or disease progression (26 studies: OR=1.01; 95% CI: 0.90–1.14), but increased the risk for venous-thromoboembolic events (44 studies: OR=1.48; 95% CI: 1.28–1.72).

CONCLUSION: Though this meta-analysis showed no significant effect of ESAs on survival or disease progression, prospectively designed, future randomised clinical trials will further examine the safety and efficacy of ESAs when used according to the revised labelling information.

Randomized, double-blind, placebo-controlled trial of every-3-week darbepoetin alfa 300 micrograms for treatment of chemotherapy-induced anemia

OBJECTIVE

Darbepoetin alfa is effective in treating chemotherapy-induced anemia (CIA). Administration of subcutaneous darbepoetin alfa every 3 weeks (Q3W) could simplify treatment through synchronization with common Q3W chemotherapy regimens. We report results from a multicenter, randomized, double-blind, placebo-controlled, phase 3 trial evaluating the efficacy and safety of fixed-dose Q3W darbepoetin alfa in patients with a wide variety of tumor types who experienced CIA.

RESEARCH DESIGN AND METHODS

Patients aged > or = 18 years with anemia (hemoglobin <11 g/dL) being treated for nonmyeloid malignancy were randomized 1:1 to receive darbepoetin alfa 300 microg (n = 193) or placebo (n = 193) subcutaneously Q3W from weeks 1 to 13 in this 16-week study. Doses could be adjusted per prespecified rules.

MAIN OUTCOME MEASURES

The primary endpoint was the proportion of patients who received > or =1 red blood cell (RBC) transfusion between week 5 and the end of the treatment period (EOTP). The study also analyzed the proportions of patients achieving a hemoglobin concentration > or =11 g/dL and subsequently maintaining hemoglobin levels above 11 g/dL, and the change in hemoglobin concentration over time.

RESULTS

The proportion of patients requiring RBC transfusions between week 5 and EOTP was significantly lower in the darbepoetin alfa-treated group than in the placebo-treated group (24 vs. 41% of patients, a 16.3% difference, p < 0.001). There were no differences between the two treatment arms in quality-of-life measures. Cardiovascular/thromboembolic adverse events were uncommon and were not associated with increases in hemoglobin levels. Study limitations suggest caution in the interpretation of these results: transfusions, the primary endpoint, were recommended but not required if hemoglobin concentrations were < or =8.0 g/dL, and protocol deviations (primarily dosing errors) occurred in approximately one-half of the patients in both treatment groups.

CONCLUSIONS

In this study, fixed-dose Q3W darbepoetin alfa appeared to be well-tolerated and effective for the treatment of CIA.

TRIAL REGISTRATION

Study 20030232; ClinicalTrials.Gov Identifier: NCT00110955.

Treating anemia of cancer with every-4-week darbepoetin alfa: final efficacy and safety results from a phase II, randomized, double-blind, placebo-controlled study

Darbepoetin alfa is an erythropoiesis-stimulating agent (ESA) approved for treating chemotherapy-induced anemia. This phase II, double-blind, placebo-controlled study examined the efficacy of darbepoetin alfa for treating anemia of cancer (AoC) in patients not receiving chemotherapy or radiotherapy. Patients were randomized 3:1 to receive darbepoetin alfa (6.75 microg/kg) or placebo every 4 weeks; the end of the study was at week 17. The primary endpoint was the percentage of patients with a hematopoietic response. Secondary endpoints included transfusion incidence and safety parameters. Efficacy analyses were performed on 162 patients in the darbepoetin alfa group and 56 patients in the placebo group. The Kaplan-Meier percentages of patients who achieved a hematopoietic response (darbepoetin alfa, 69%; placebo, 24%) or achieved the target hemoglobin (darbepoetin alfa, 85%; placebo, 50%) differed significantly between treatment groups. The transfusion incidence did not differ between treatment groups probably because of the low baseline transfusion rates in AoC patients. The incidence of adverse events (including on-study deaths) was similar in both groups. In conclusion, darbepoetin alfa appeared to be well tolerated and significantly increased hemoglobin levels in these AoC study patients.

Phase 2, single-arm trial to evaluate the effectiveness of darbepoetin alfa for correcting anaemia in patients with myelodysplastic syndromes

Patients with myelodysplastic syndromes (MDS) often develop anaemia resulting in frequent transfusions and fatigue. Darbepoetin alfa is an erythropoiesis-stimulating agent (ESA) approved for treating chemotherapy-induced anaemia. This single-arm, phase 2 study examined the efficacy of darbepoetin alfa 500 μg every 3 weeks (Q3W) for treating anaemia in low-risk MDS patients (after 6 weeks, poor responders received darbepoetin alfa 500 μg every 2 weeks). The primary end-point was the incidence of erythroid responses (International Working Group criteria) after 13 weeks of therapy. Secondary end-points included the incidence of erythroid responses at weeks 28 and 55, [or weeks 27 and 53 for dose escalations to every two weeks (Q2W)], and safety parameters. Analyses were stratified by the patient's previous ESA therapy status [ESA-naïve (n = 144) vs. prior ESA-treated (n = 62)]. After 13 weeks of therapy, 49% of ESA-naïve patients and 26% of prior ESA-treated patients achieved a major erythroid response. After 53/55 weeks, 59% of ESA-naïve patients and 34% of prior ESA-treated patients achieved a major erythroid response; 82% of ESA-naïve patients and 55% of prior ESA-treated patients achieved target haemoglobin of 110 g/l. Thromboembolic or related adverse events occurred in 2% of patients; no pulmonary embolisms were reported. In conclusion, darbepoetin alfa, 500 μg Q3W appeared well tolerated and increased haemoglobin levels in low-risk MDS patients.

A randomized, open-label, multicenter trial of immediate versus delayed intervention with darbepoetin alfa for chemotherapy-induced anemia

The optimal hemoglobin concentration at which to initiate erythropoietic therapy for chemotherapy-induced anemia (CIA) is not well defined. This randomized, open-label, multicenter study evaluated the ability of darbepoetin alfa (300 microg every 3 weeks) to maintain hemoglobin levels > or =10 g/dl in patients with CIA (hemoglobin > or =10.5 g/dl and < or =12.0 g/dl) randomized 1:1 to an immediate-intervention group (received darbepoetin alfa immediately) or observation group (received darbepoetin alfa if hemoglobin fell to <10 g/dl). In 201 evaluable patients, there was a significant difference between the two groups in the Kaplan-Meier proportion of patients with a hemoglobin decrease to <10 g/dl during weeks 1-13 (test period) (primary endpoint): 29% for immediate-intervention patients versus 65% for observation patients. Sixty-four patients in the observation group received darbepoetin alfa (delayed-intervention subgroup). The Kaplan-Meier proportion of patients who received transfusions was lower in the immediate-intervention group than in the delayed-intervention subgroup (14% versus 31% for the test period; 17% versus 36% over the whole study). The target hemoglobin level (> or =11 g/dl) was achieved by a higher percentage of patients (crude percentage) in less time in the immediate-intervention group (94% in 2 weeks) than in the delayed-intervention subgroup (73% in 6 weeks); hemoglobin endpoints for the delayed-intervention subgroup were calculated from recalibrated study week 1 (the date patients first received darbepoetin alfa). For both groups, a higher mean change in hemoglobin from baseline led to a greater improvement in Functional Assessment of Cancer Therapy-Fatigue scores. In conclusion, immediate intervention resulted in a significantly lower proportion of patients who experienced a decline in hemoglobin, lower requirement for transfusions, and greater proportion of patients achieving and maintaining the target hemoglobin level.

Baseline predictors of response to treatment with darbepoetin-alpha (DA) in anemic patients with low-risk myelodysplastic syndrome (MDS)

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Background: Patients (pts) with MDS often develop anemia, resulting in fatigue and an increased requirement for transfusions. The erythropoiesis-stimulating agent (ESA) DA can raise hemoglobin (Hb) levels in low-risk MDS pts. Previous analyses suggest that baseline (BL) endogenous erythropoietin (eEPO) levels and French-American-British (FAB) disease category are predictors of response to ESAs. Methods: This was a phase 2, open-label, 52-week (wk) study of DA administered 500 mcg every 3 wks (Q3W) to anemic (Hb=11g/dL), low- or intermediate-risk MDS pts. Pts received 500 mcg DA Q2W if they did not respond by wk 7. The last DA dose was at wk 52; end of study was wk 53 or 55 for pts receiving DA Q2W or Q3W, respectively. The primary endpoint was % pts with an erythroid response (International Working Group criteria) by wk 13. Other endpoints included change from BL in Hb and FACT-F score. Exploratory analyses examined the incidence of erythroid responses adjusted by FAB category (refractory anemia [RA], RA with ringed sideroblasts [RARS], or RA with excess blasts [RAEB]). Results: Final 53/55 wk data will be presented. Results were stratified by whether pts received an ESA before enrollment (ESA-naive [ESA-N] vs ESA-treated [ESA-T]). ESA-T pts are a heterogeneous group and their data are difficult to interpret; thus, predictors of response will be presented for ESA-N pts only. Of 144 ESA-N pts, 56% had RA, 37% had RARS, and 7% had RAEB. Most ESA-N pts achieved the target Hb and had a major erythroid response ( Table ). Pts with RA were more likely to achieve a major erythroid response than pts with RARS or RAEB. For ESA-T pts, demographics and type/length of ESA treatment will be presented. Of all pts, serious adverse events (SAEs) were reported in 62 (30%) pts and treatment-related SAEs in 2 (1%) pts. Conclusions: FAB category may affect response to DA in MDS pts. Additional data will be presented on the effect of BL eEPO, transfusion needs, and previous ESA treatment on response and duration of response.

[Table: see text]

Efficacy and Safety of Every‐2‐Week Darbepoetin Alfa in Patients with Anemia of Cancer: A Controlled, Randomized, Open‐Label Phase II Trial

This randomized, controlled trial evaluated the effect of darbepoetin alfa on hospitalization days, transfusion requirements, hemoglobin levels, and fatigue in patients with anemia of cancer (AOC). Eligible patients were anemic (hemoglobin <or=11 g/dl) due to cancer, >or=18 years old, and had not received chemotherapy or radiotherapy within 4 weeks of study screening. Patients were randomized 4:1 to receive darbepoetin alfa, 3.0 microg/kg every 2 weeks (Q2W) (n = 226), or observation only for 12 weeks (n = 59), followed by an optional 9 weeks of darbepoetin alfa, 3.0 microg/kg Q2W. Endpoints were compared between the two treatment arms at week 13. A planned interim analysis indicated that assumptions regarding hospitalization in the study design were incorrect, so the study was terminated early. Therefore, results for the primary endpoint should be interpreted cautiously. The hospitalization rate was similar (0.5 days) for both the darbepoetin alfa and observation groups (p = .73). Transfusion incidence (weeks 5-12) was significantly lower for darbepoetin alfa patients (8%) than for observation patients (22%) (p = .0092). By week 13, hemoglobin increased by 2.1 g/dl in patients receiving darbepoetin alfa, compared with 0.1 g/dl in the observation group p < .0001. Hemoglobin improvements were paralleled by an increase in Functional Assessment of Cancer Therapy-Fatigue score (mean change in score at week 13: darbepoetin alfa, 6.0; observation, 2.2; p < .05). Darbepoetin alfa Q2W can significantly improve hemoglobin levels and reduce transfusion requirements in patients with AOC, resulting in significant improvements in health-related quality of life.

The Effectiveness of Darbepoetin Alfa Administered Every 3 Weeks on Hematologic Outcomes and Quality of Life in Older Patients With Chemotherapy‐Induced Anemia

Chemotherapy-induced anemia (CIA) may substantially impact the health-related quality of life (HRQoL) of older cancer patients. This exploratory analysis evaluated the effect of darbepoetin alfa administered as a fixed dose (300 microg) every 3 weeks (Q3W) on hematologic outcomes, HRQoL, and safety in older (> or =65 years old) versus younger (<65 years old) patients with CIA (hemoglobin <11 g/dl). Patients were categorized by age at screening: <65, > or =65 to <70, > or =70 to <75, > or =75 to <80, and > or =80 years old. Patients who received at least one dose of darbepoetin alfa were included in the analysis; of 1,493 patients, 724 were > or =65 years old. Age did not appear to influence hematologic outcomes after treatment with darbepoetin alfa; in all age categories, similar percentages of patients (78%-80%) achieved the target hemoglobin in approximately the same time (4-5 weeks). Also, the percentage of patients in each age category who received RBC transfusions was reduced from 10%-13% in month 1 to 2%-4% in month 4. Although younger patients reported the greatest improvement in HRQoL scores, approximately one half in each older age category reported clinically significant improvement in fatigue, and improvement in the Energy and Overall Health Assessment and Work Productivity and Activity Impairment scales. There were no treatment-related deaths. Treatment-related thromboembolic events were reported by <1% of patients <65 years old and <1% of patients > or =65 to <70 and > or =70 to <75 years old. Darbepoetin alfa Q3W appeared well tolerated and effective for treating older patients with CIA.

The effectiveness of darbepoetin alfa administered at 300 mcg every 3 weeks on clinical outcomes in elderly patients with chemotherapy-induced anemia

18511

Background: Chemotherapy-induced anemia (CIA) is common in patients (pts) receiving chemotherapy, and reduces health-related quality of life. The primary objective of this exploratory analysis was to describe the effectiveness of darbepoetin alfa administered at 300 mcg every 3 weeks (Q3W) in elderly (≥ 65 years old) and younger pts (< 65 years old) with CIA. Methods: We analyzed data on 1493 pts, enrolled in a multicenter, open-label, 16-week study and who received ≥ 1 dose of darbepoetin alfa. Eligible pts were ≥ 18 years old, had a non-myeloid malignancy, and were anemic (hemoglobin [Hb] < 11 g/dL). Pts were analyzed stratified by age (≥ 65 and < 65 years old) and baseline (BL) Hb (< 10 or ≥ 10 g/dL). Hb-based endpoints were analyzed using 2 approaches: the last value carried forward (LVCF) method, where missing Hb values or values within 28 days of a red blood cell (RBC) transfusion were imputed, or an available data approach, where missing Hb values were not imputed. Pt-reported outcomes were assessed using the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) scale. Results: Pt demographics and disease characteristics varied between the age strata: in the ≥ 65-stratum (mean age = 73.7, n = 724), 52% of pts were women and the most common cancer was gastrointestinal (27%); in the < 65-stratum (mean age = 52.1, n = 769), 69% of pts were women and the most common cancer was breast (41%). Mean (SD) BL FACT-F scores for pts ≥ 65 and < 65 were 27.5 (12.8) vs 27.2 (12.1) for the < 10-g/dL strata and 29.0 (12.5) vs 27.5 (12.0) for the ≥ 10-g/dL strata. Study endpoints are shown in the table. The safety profile was as expected for each age group. Conclusions: Darbepoetin alfa 300 mcg Q3W appears to be as effective in achieving and maintaining Hb between 11 to 13 g/dL in elderly pts as in younger pts with CIA. Since chemotherapy is often administered Q3W, synchronizing darbepoetin alfa treatment with pts’ chemotherapy schedules may simplify the treatment of CIA in this pt population.

[Table: see text]

[Table: see text]

Effectiveness of darbepoetin alfa 300 mcg every 3 weeks in patients with chemotherapy-induced anemia

18545

Background: Patients (pts) receiving chemotherapy (CTX) often experience anemia resulting in decreased quality of life. We performed a post hoc combined analysis of 2 clinical studies of darbepoetin alfa (DA) 300 mcg every 3 weeks (Q3W), allowing for comparison of larger treatment groups. Methods: Eligibility criteria of the 2 studies were similar: pts ≥ 18 yrs old with nonmyeloid malignancy, anemia (hemoglobin [Hb] < 11 g/dL), and receiving CTX. Study 1 (20030232) was a phase 3, randomized, placebo-controlled, double-blind, study involving 16 wks of treatment with end of treatment phase (EOTP) visit at wk 19. Study 2 (20030206) was a single-arm, open-label, phase 4 study involving 13-wks of treatment with EOTP visit at wk 16. Efficacy endpoints included: percentage of pts achieving target Hb (≥ 11 g/dL without RBC transfusion [TFN] within 28 days), pts requiring TFNs between wk 1 and EOTP, pts requiring TFNs between wk 5 and EOTP, pts with a ≥ 3-point change in FACT-F score, and pts achieving ≥ 1-g/dL increase in Hb after 4 wks of therapy. Results: In both studies, 61% of pts were women and 79% were white. The mean (SD) age was 64.5 years (12.1) for Study 1 and 62.6 years (13.3) for Study 2. The most common tumor type was breast (26% in Study 1; 29% in Study 2). Mean (SD) baseline (BL) Hb values were 10.1 (0.9) and 10.1 (0.7) g/dL for Study 1 and Study 2 respectively, and mean (SD) baseline FACT-F scores were 27.3 (12.8) and 27.9 (12.3) respectively. See Table for endpoints. Combined analysis showed that increasing Hb by ≥ 1 g/dL after 4 wks of therapy was a poor predictor of clinical outcomes (avoidance of TFN, sensitivity = 56.2%; achievement of Hb target, sensitivity = 57.8%). Safety outcomes were similar and expected for this population. DA appeared to be well-tolerated. No pts exhibited neutralizing antibodies to DA. Conclusions: This combined analysis provides further evidence of the effectiveness of DA Q3W dosing in this pt population. This dosing interval may facilitate the administration of DA in synchronization with Q3W CTX regimens.

[Table: see text]

[Table: see text]

Evaluating if darbepoetin alfa efficacy and safety in patients with chemotherapy-induced anemia is affected by the disease stage of the patient

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Background: Cancer patients (pts) often develop chemotherapy-induced anemia (CIA), resulting in increased transfusion incidence and fatigue. Darbepoetin alfa (DA) is an erythropoiesis-stimulating agent that can reduce the incidence of transfusions, increase hemoglobin (Hb) levels to a range of 11 to 13 g/dL (as recommended by evidence-based guidelines), and decrease fatigue in pts with CIA. The 74-hour half-life of DA allows it to be effectively administered weekly (QW), every 2 weeks (Q2W), or every 3 weeks (Q3W). DA treatment can also be synchronized with chemotherapy (Glaspy et al., 2005). Here we examined if the efficacy and safety of DA for treating CIA is affected by the disease stage of the pt. Methods: Eight clinical trials (including single-arm, active-controlled, and placebo-controlled studies) were analyzed that described the administration of DA QW (2 studies), Q2W (3 studies), or Q3W (3 studies) to pts with CIA. Tumor-Nodes-Metastases (TNM) classification was used to define disease stage of I, II, III, or IV. A clinically meaningful endpoint evaluated was the proportion of pts achieving a target Hb of ≥ 11 g/dL. Other endpoints included incidence of transfusions, change in FACT-F score at end of study from baseline, and incidence of adverse events. Results: A high percentage of pts in all disease stages achieved a target Hb of ≥ 11 g/dL in response to DA treatment (see Table ). Early stage pts were seen to benefit at least as much as later stage pts. A similar trend was seen for the other efficacy and safety endpoints (data will be presented). Conclusions: The present analysis suggests that DA administered QW, Q2W, or Q3W can effectively correct anemia when administered to pts in either early or late disease stages. The potential to synchronize DA treatment and chemotherapy regardless of disease stage may increase pt convenience by reducing the number of clinic visits.

[Table: see text]

[Table: see text]

Randomized comparison of every-2-week darbepoetin alfa and weekly epoetin alfa for the treatment of chemotherapy-induced anemia: the 20030125 Study Group Trial

PURPOSE

Chemotherapy-induced anemia is widely treated in the United States with darbepoetin alfa (DA) or epoetin alfa (EA). This noninferiority study systematically compares efficacy and safety of DA and EA using common doses and schedules used in clinical practice.

METHODS

Patients had a diagnosis of nonmyeloid malignancy with > or = 8 weeks of planned chemotherapy, age >or = 18 years, and anemia (hemoglobin < or = 11 g/dL). Patients were randomly assigned 1:1 to DA 200 microg every two weeks (Q2W) or EA 40,000 units every week (QW) for up to 16 weeks with identical dose adjustment rules. Efficacy was assessed by the incidence of RBC transfusion (Kaplan-Meier estimate). The definition of noninferiority was that the upper 95% CI limit of the observed difference in RBC transfusions between groups was less than 11.5%; this noninferiority margin was based on the treatment effect observed in placebo-controlled EA studies.

RESULTS

Of 1,220 patients randomly assigned, 1,209 received > or = one dose of the study drug. Common tumor types were lung (26%), breast (21%), and gastrointestinal (18%). Transfusion incidence from week 5 to the end of the treatment phase (the primary end point) was 21% in the DA group and 16% in the EA group; noninferiority was concluded because the upper 95% CI limit of the difference between groups (10.8%) was below the prespecified noninferiority margin. Sensitivity analyses using alternate statistical methods and analysis sets yielded similar results. Hemoglobin, quality of life, and safety end points further support equivalency of the erythropoietic therapies.

CONCLUSION

This large, phase III study demonstrates comparable efficacy of DA Q2W and EA QW. Less frequent dosing offers potential benefits for patients, caregivers and health care providers.

Darbepoetin Alfa Administered Every Three Weeks Is Effective for the Treatment of Chemotherapy‐Induced Anemia

Patients with cancer receiving chemotherapy often have chemotherapy-induced anemia (CIA) and reduced quality of life. Darbepoetin alfa can effectively treat CIA when administered at an extended dosing interval of once every 3 weeks (Q3W). Darbepoetin alfa administered Q3W may allow synchronization of darbepoetin alfa therapy with chemotherapy administered Q3W. This multicenter, open-label, 16-week study evaluated the effectiveness and safety of darbepoetin alfa administered as a fixed dose (300 mug) Q3W in patients with CIA. Eligible patients (> or =18 years) were anemic (hemoglobin <11g/dl), had a nonmyeloid malignancy, and were receiving multicycle chemotherapy. This analysis includes 1,493 patients who received at least one dose of darbepoetin alfa. The effect of baseline hemoglobin (<10 or > or =10 g/dl) on clinical outcomes was evaluated. Patients in the > or =10-g/dl stratum achieved the hemoglobin target range (11-13 g/dl)in less time than patients in the <10-g/dlstratum (3 weeks vs. 9 weeks). More patients in the > or =10-g/dl stratum achieved the hemoglobin target range (87% vs. 66%); however, similar proportions of patients in both strata maintained hemoglobin within the target range (73% vs. 71%). Fewer patients in the > or =10-g/dl stratum received RBC transfusions from week 5 to the end of the study (12% vs. 28%). Over 50% of patients in both strata reported clinically significant improvements (> or =3-point increase) in Functional Assessment of Cancer Therapy-Fatigue score. Twenty-eight percent of patients reported serious adverse events; 3% of all patients had a venous or arterial thrombotic event. This study demonstrates that darbepoetin alfa Q3W is well tolerated and effective for treating CIA.

Treatment of Chemotherapy-Induced Anemia in Breast Cancer: Results of a Randomized Controlled Trial of Darbepoetin Alfa 200 μg Every 2 Weeks Versus Epoetin Alfa 40,000 U Weekly

BACKGROUND

Current chemotherapy regimens for breast cancer result in high incidences of anemia, which can be treated with erythropoietic agents. The relative efficacy of darbepoetin alfa and epoetin alfa was explored in this phase II, open-label, randomized, multicenter trial in anemic patients with breast cancer receiving chemotherapy.

PATIENTS AND METHODS

Patients were randomized at a 1:1 ratio to receive darbepoetin alfa 200 microg every 2 weeks (n = 72) or epoetin alfa 40,000 U weekly (n = 69) for < or = 16 weeks. Clinical and hematologic endpoints and validation of a novel patient satisfaction questionnaire for anemia treatment were evaluated for all patients randomized to receive > or = 1 dose of study drug.

RESULTS

Baseline characteristics were generally similar between treatment groups. Mean changes in hemoglobin (Hb) level from baseline were similar at 1.9 g/dL for darbepoetin alfa and 1.7 g/dL for epoetin alfa. Hematopoietic responses (> or = 2 g/dL increase in Hb level from baseline or Hb level > or = 12 g/dL) were also similar between groups (88% for darbepoetin alfa and 81% for epoetin alfa). The proportions of patients who received a transfusion during treatment were 6% (95% CI, 0-11%) for darbepoetin alfa and 16% (95% CI, 7%-25%) for epoetin alfa. Most patients (67 patients receiving darbepoetin alfa [93%]; 61 patients receiving epoetin alfa [90%]) exhibited a clinically meaningful target Hb level > or = 11 g/dL. No differences in safety were observed.

CONCLUSION

These results suggest that, in patients with breast cancer, darbepoetin alfa 200 microg every 2 weeks and epoetin alfa 40,000 U weekly result in comparable clinical outcomes for the treatment of chemotherapy-induced anemia.

A randomized comparison of every-2-week darbepoetin alfa and weekly epoetin alfa for the treatment of chemotherapy-induced anemia in patients with breast, lung, or gynecologic cancer

An important clinical question is the relative efficacy of the most common dosages of darbepoetin alfa (Aranesp; Amgen Inc.; Thousand Oaks, CA) 200 microg every 2 weeks (Q2W) and epoetin alfa (Procrit; Ortho Biotech Products, LP; Raritan, NJ) 40,000 U weekly (QW) for the treatment of chemotherapy-induced anemia. We designed three concurrent randomized, open-label, multicenter, identical trials (with the exception of tumor type criteria of breast, gynecologic, or lung cancer) of darbepoetin alfa and epoetin alfa in patients with chemotherapy-induced anemia to validate the Patient Satisfaction Questionnaire for Anemia (PSQ-An) treatment tool and to compare the efficacies and safety profiles of these two agents. In each trial, patients were randomized 1:1 to receive either darbepoetin alfa at a dose of 200 microg Q2W or epoetin alfa at a dose of 40,000 U QW for up to 16 weeks. The PSQ-An was assessed for validity, feasibility, and reliability. Secondary clinical endpoints were analyzed using the primary analysis set. Both individual trial analyses and a protocol-specified combined analysis of data from all three trials were conducted. Overall, 312 patients (157 darbepoetin alfa; 155 epoetin alfa) were randomized and received study drug. Baseline characteristics were similar in both treatment groups in each trial and overall. The PSQ-An was valid, feasible, and reliable. In general, no difference between treatment groups was observed for hemoglobin- and transfusion-based endpoints in each individual trial or in the combined analysis. From exploratory analyses, achievement and maintenance of a hemoglobin target range (11-13 g/dl) were similar in both groups. No differences in safety were observed. With the PSQ-An, formal comparisons of the impact of anemia therapies on patients and caregivers can be made in future prospective studies. Further, darbepoetin alfa (200 microg Q2W) and epoetin alfa (40,000 U QW) appear to achieve comparable clinical and hematologic outcomes.