Improvement in health-related quality of life in patients with haemophilia B treated with nonacog beta pegol, a new extended half-life recombinant FIX product

Knowledge gaps in health-related quality of life research performed in children with bleeding disorders - A scoping review

INTRODUCTION

Bleeding disorders (BDs) may influence health-related quality of life (HRQoL) in children and caregivers. Measuring HRQoL gives insight into domains requiring support and provides an opportunity to evaluate the effects of novel therapies.

AIM

To gain insight in the current body of literature on HRQoL in children with BDs in order to identify knowledge gaps for research and further development of this field.

METHODS

Scoping review.

RESULTS

We included 53 articles, describing studies mainly performed in Europe and North-America (60.4%) and mostly within the last ten years. Only 32% studies included children <4 years. Almost all studies (47/53, 88.7%) were performed in boys with haemophilia, pooling haemophilia A and B (n = 21) and different disease severities (n = 20). Thirteen different generic and five disease-specific HRQoL-questionnaires were applied; all questionnaires were validated for haemophilia specifically. Six (11,3%) combined generic and disease-specific questionnaires. Self-reports were most frequently applied (40/53, 75.5%), sometimes combined with proxy and/or parent-reports (17/53, 32.1%). Eleven studies used a reference group (20.8%). Statistical analyses mostly consisted of mean and SD (77.4%).

CONCLUSION

HRQoL-research is mainly performed in school-aged boys with haemophilia, treated in developed countries. Pitfalls encountered are the pooling of various BDs, subtypes and severities, as well as the application of multiple generic questionnaires prohibiting comparison of results. More attention is needed for broader study populations including other BDs, young children, feminine bleeding issues and platelet disorders, as well as the use of HRQoL as an effect-measurement tool for medical interventions, and more thorough statistical analysis.

Efficacy of rFIXFc versus N9-GP Prophylaxis in Patients with Hemophilia B: Matching-Adjusted Indirect Comparison of B-LONG and PARADIGM 2 Trials

Purpose

For patients with hemophilia B, extended half-life factor IX (FIX) products are available for prophylaxis and for treating bleeds. Different methods are used to extend the half-lives of recombinant FIX Fc fusion protein (rFIXFc) and nonacog beta pegol (N9-GP). This affects their biodistribution and plasma FIX levels, although differences do not always correlate with clinical outcomes. A matching-adjusted indirect comparison (MAIC) of prophylaxis with rFIXFc and N9-GP was performed, based on licensed dosing in the European Union.

Patients and Methods

Combined rFIXFc data from the weekly and individualized interval prophylaxis arms of the B-LONG clinical trial, and N9-GP data from the 40 IU/kg once-weekly prophylaxis arm of PARADIGM 2 were used in a MAIC. Individual patient data for rFIXFc (n=87) were matched to aggregated data for N9-GP (n=29). Estimated annualized bleeding rates (ABRs) for rFIXFc were recalculated using a Poisson regression model with adjustment for over-dispersion, and compared with ABRs reported for N9-GP, using incidence rate ratios (IRRs) with 95% confidence interval (CI).

Results

There was no evidence of significant differences in estimated ABRs between prophylaxis with rFIXFc and N9-GP. Analysis of pooled rFIXFc weekly and interval-adjusted dosing compared with N9-GP 40 IU/kg once weekly produced estimated ABRs of 2.59 versus 2.51 (IRR 1.03; 95% CI 0.56-1.89), as well as 1.34 versus 1.22 (IRR 1.10; 95% CI 0.42-2.91) and 1.13 versus 1.29 (IRR 0.88; 95% CI 0.47-1.63) for overall, spontaneous, and traumatic bleeding events, respectively.

Conclusion

The study did not reveal any significant differences in the efficacy of rFIXFc and N9-GP prophylaxis. Given differences in trough levels (rFIXFc dosing was targeted to achieve a trough 1-3 IU/dL above baseline versus a reported estimated N9-GP mean trough of 27.3 IU/dL), interpreting plasma FIX levels as potential surrogate efficacy markers requires consideration of compound-specific pharmacokinetic profiles.

Reclassifying hemophilia to include the definition of outcomes and phenotype as new targets

Hemophilia is classified into mild, moderate, and severe based on coagulation factor activity levels. Factor replacement and prophylaxis regimens in persons with hemophilia have helped to reduce bleeding and its related complications. With several newer treatments, some already approved and others soon to be, there may be a need to consider health-related quality of life in addition to bleed prevention as the goals of providing comprehensive care to persons with hemophilia. In this article, we discussed the reasons why such an approach may be relevant and call for the International Society of Thrombosis and Haemostasis to revisit the current classification of hemophilia.

rFIXFc prophylaxis improves pain and levels of physical activity in haemophilia B: Post hoc analysis of B-LONG using haemophilia-specific quality of life questionnaires

INTRODUCTION

Recurrent bleeding in severe haemophilia B causes painful hemarthroses and reduces capacity for physical activity. Recombinant factor IX Fc fusion protein (rFIXFc) prophylaxis results in low annualised bleeding rates, with the potential to improve patients' health-related quality of life (HRQoL).

AIM

To present a post hoc analysis of data from B-LONG describing change over time in patient-reported outcomes associated with pain and physical activity.

METHODS

Patients (≥12 years) who received weekly dose-adjusted or interval-adjusted rFIXFc prophylaxis and completed the Haemophilia-Specific QoL questionnaire for adolescents (Haemo-QoL) or adults (Haem-A-QoL) at baseline (BL) and end of study (EoS). Individual level changes in items of the 'Physical Health' and 'Sports and Leisure' domains, categorised as 'never/rarely/seldom' or 'sometimes/often/all the time', were analysed using McNemar's test to compare distribution of responses at EoS versus BL.

RESULTS

At EoS versus BL, a significantly greater proportion of patients did not experience painful swellings (64% vs. 44%; P = .004), painful joints (44% vs. 28%; P = .003) or pain when moving (54% vs. 41%; P = .026). Additionally, at EoS versus BL, patients were less likely to avoid participating in sports like football (30% vs. 8%; P = .002), avoid sports due to their haemophilia (47% vs. 27%; P = .007), or experience difficulty walking as far as they wanted (63% vs. 43%; P = .001). The proportion of patients who played sports as much as the general population was numerically increased (52% vs. 37%; P = .033) at EoS versus BL.

CONCLUSION

Results of the analysis suggest that over time, rFIXFc prophylaxis is associated with significant improvements in pain and physical functioning. This contributes to previous evidence of overall HRQoL improvements in patients with haemophilia B treated with rFIXFc.

The impact of extended half-life factor concentrates on patient reported health outcome measures in persons with hemophilia A and hemophilia B

BACKGROUND

Recombinant factors VIII and IX Fc (rFVIIIFc/rFIXFc) were the only available extended half-life (EHL) products in Canada during 2016 to 2018.

OBJECTIVES

To evaluate if patient-reported outcome measures (PROMs) improved in Canadian persons with hemophilia who switched from standard half-life (SHL) to EHL products (rFVIIIFc/rFIXFc).

PATIENTS/METHODS

This prospective cohort study enrolled persons with moderate or severe hemophilia aged ≥6 years who switched to rFVIIIFc/rFIXFc (2016-2018) and those who remained on SHL. Health-related quality of life (HRQoL) was assessed using the Haemophilia-specific Quality of Life (Haem-A-QoL) and 36-item Short-Form Survey (SF-36) at baseline, 3-months, 12 months, and 24 months. Other PROMs included the Work Productivity and Impairment Questionnaire, chronic pain scale, partner/parent ratings of mood, International Physical Activity Questionnaire, and Treatment Satisfaction Questionnaire for Medication. We identified meaningful changes using minimally important difference for SF-36 and responder definition for Haem-A-QoL.

RESULTS

We enrolled 25 switchers (16 rFVIIIFc, 9 rFIXFc) and 33 nonswitchers. Those switched to rFVIIIFc/rFIXFc had improved overall HRQoL, and improved subscale physical activity, mental health, and social functioning at 3 months. The rFIXFc switchers had improved chronic pain and ability to engage in normal activities while the rFVIIIFc switchers had improved treatment satisfaction. There was no change in work impairment after the switch. Observed improvement disappeared by 24 months in most domains.

CONCLUSION

Switching from SHL to rFVIIIFc/rFIXFc resulted in short-term meaningful improvement in overall HRQoL and other PROMs in a small proportion. Longitudinal changes on PROMs are affected by ceiling effects and response shift, warranting further studies in instrument optimization in the era of EHL and nonfactor products.

Recombinant factor IX-Fc fusion protein in severe hemophilia B: Patient-reported outcomes and health-related quality of life

INTRODUCTION

In 2017, all people with severe hemophilia B in Ireland switched to recombinant factor IX Fc fusion protein concentrate (rFIXFc) prophylaxis. Patient-reported outcomes (PROs) and health-related quality of life (HRQoL) are important to evaluate with new treatments.

AIMS

To assess HRQoL in people with severe hemophilia B and their experience after switching to rFIXFc prophylaxis.

METHODS

Participants completed a Patient Reported Outcomes Burden and Experience (PROBE) questionnaire on initiation and following two years of rFIXFc prophylaxis. The PROBE questionnaire has four domains: demographics, general health, haemophilia-specific, and European Quality of Life 5-Dimensions (EQ-5D-5L) questionnaire.

RESULTS

Twenty-three participants completed the questionnaire at both time points. The number of activities where chronic pain occurred and interfered with the activity was reduced by 25% and 33%, respectively (P < .001), following two years of rFIXFc prophylaxis. There was a 9% decrease in chronic pain during the second year of rFIXFc prophylaxis compared to baseline, but the rate remained high, at 74%. A 25% reduction in the number of affected activities of daily living (ADLs) was reported following 2 years of rFIXFc prophylaxis (P = .007). The most common health problems were arthritis, hypertension, anxiety/depression, and gingivitis. The median EQ-5D-5L score was similar following two years of rFIXFc prophylaxis, 0.76 (range, -0.01 to 0.95), compared to 0.77 (range, 0.36-1) at baseline.

CONCLUSION

This study of real-world patient experience using PROs demonstrates a reduction in chronic pain and improvement in ADLs in participants after switching to rFIXFc prophylaxis. It provides important insights into patient-identified health care needs and living with severe hemophilia B.

Clotting factor concentrates for preventing bleeding and bleeding-related complications in previously treated individuals with haemophilia A or B

BACKGROUND

The hallmark of severe hemophilia (A or B) is recurrent bleeding into joints and soft tissues with progressive joint damage, despite on-demand treatment. Prophylaxis has long been used, but not universally adopted, because of medical, psychosocial, and cost controversies.

OBJECTIVES

To determine the effectiveness of clotting factor concentrate prophylaxis in managing previously-treated individuals with hemophilia A or B.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Coagulopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. In addition, we searched MEDLINE and Embase and online trial registries. Most recent search of Group's Coagulopathies Trials Register: 24 February 2021.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs evaluating people with hemophilia A or hemophilia B, who were previously treated with clotting factor concentrates to manage their hemophilia.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed trials for eligibility, assessed risk of bias and extracted data. The authors used the GRADE criteria to assess the certainty of the evidence.

MAIN RESULTS

Ten trials (including 608 participants) were eligible for inclusion. Eight of the trials (477 participants) had arms comparing two or more prophylactic regimens to one another and four of the trials (n = 258) compared prophylaxis to on-demand treatment (two trials had multiple arms and were included in both comparisons). Comparison of two or more prophylactic regimens For trials comparing one prophylaxis regimen to another, given the heterogeneity of the data, none of the data were pooled for this comparison. Considering the individual trials, three trials reported the primary outcome of joint bleeding, and none showed a dfference between dosing regimens (low-certainty evidence). For the secondary outcome of total bleeding events, prophylaxis with a twice-weekly regimen of FIX likely results in reduced total bleeds compared to a once-a-week regimen of the same dose, mean difference (MD) 11.2 (5.81 to 16.59) (one trial, 10 participants, low-certainty evidence). Transient low-titer anti-FVIII inhibitors were reported in one of the trials. Blood-transmitted infections were not identified. Other adverse events reported include hypersensitivity, oedema, and weight gain. These were, however, rare and unrelated to study drugs (very low-certainty evidence). Comparison of prophylactic and on-demand regimens Four of the trials (258 participants) had arms that compared prophylaxis to on-demand treatment. Prophylaxis may result in a large decrease in the number of joint bleeds compared to on-demand treatment, MD -30.34 (95% CI -46.95 to -13.73) (two trials, 164 participants, low-certainty evidence). One of these trials (84 participants) also reported the long-term effects of prophylaxis versus on-demand therapy showing improved joint function, quality of life, and pain; but no differences between groups in joint structure when assessed by magnetic resonance imaging (MRI). In one trial (84 participants) validated measures for joint health and pain assessment showed that prophylaxis likely improves joint health compared to an on-demand regimen with an estimated change difference of 0.94 points (95% CI 0.23 to 1.65) and improves total pain scores, MD -17.20 (95% CI -27.48 to -6.92 (moderate-certainty evidence). Two trials (131 participants) reported that prophylaxis likely results in a slight increase in adverse events, risk ratio 1.71 (1.24 to 2.37) (moderate-certainty evidence). No inhibitor development and blood-transmitted infections were identified. Overall, the certainty of the body of evidence was judged to be low because of different types of bias that could have altered the effect.   AUTHORS' CONCLUSIONS: There is evidence from RCTs that prophylaxis, as compared to on-demand treatment, may reduce bleeding frequency in previously-treated people with hemophilia. Prophylaxis may also improve joint function, pain and quality of life, even though this does not translate into a detectable improvement of articular damage when assessed by MRI.  When comparing two different prophylaxis regimens, no significant differences in terms of protection from bleeding were found. Dose optimization could, however, result in improved efficacy. Given the heterogeneity of the data, pooled estimates were not obtained for most comparisons.  Well-designed RCTs and prospective observational controlled studies with standardised definitions and measurements are needed to establish the optimal and most cost-effective treatment regimens.

Extended half-life recombinant products in haemophilia clinical practice - Expectations, opportunities and challenges

Extended half-life (EHL) products have shown robust efficacy in clinical trials, whilst allowing for less intense treatment regimens when compared with standard half-life products. Regimen optimisation with EHL products could lead to further improvements in bleeding rates, quality of life and reductions in treatment burden. Patients now expect good efficacy, a lower treatment burden and equivalent safety when compared with standard half-life products. As our knowledge base grows these expectations have evolved and targeting an annualised bleeding rate of zero has become a more realistic clinical goal. Personalised prophylaxis can help patients achieve these goals. However, a number of challenges still remain, including cost, challenges in predicting outcomes for patients and differences in patients' and clinicians' expectations. When switching a patient, comprehensive patient care can reduce the impact of these issues. This review presents in brief the protein therapeutics with an extended half-life, including key trial results, challenges of chronic care that impact on patients' outcomes and how the modified proteins might help address some of these issues. In addition, practical steps for managing the switch to EHL products are presented.

Health-related quality of life in paediatric haemophilia B patients treated with rIX-FP

INTRODUCTION

Frequent infusions and bleeds can impact on the health-related quality of life (HRQoL) of paediatric haemophilia B patients. rIX-FP (IDELVION^® ) is a fusion protein linking recombinant factor IX with recombinant albumin, and is associated with low bleeding rates with a weekly regimen, which could improve HRQoL.

AIMS

To measure the effect of rIX-FP prophylaxis on the HRQoL of paediatric patients and treatment satisfaction in their caregivers using the Haemo-QoL and Hemo-SAT_P questionnaires, respectively.

METHODS

At baseline and end-of-study (EOS), patients 4-11 years old participating in the PROLONG-9FP program answered the Haemo-QoL questionnaire and gave information on their socio-demographic data and physical activity. Caregivers completed the Hemo-Sat_P . Minimal important differences (MID) (|Cohen's d| > 0.5) between baseline and EOS and the number of responders (patients with meaningful subject-level improvements over time) at EOS were calculated.

RESULTS

Twenty patients (age group I: 4-7 years old [n = 12]; age group II: 8-12 years old [n = 8]) completed the Haemo-QoL questionnaire at baseline. MIDs were found in age group I representing improvement for "physical health" (d = -0.547) domain; 60% of patients were responders for "physical health." In age group II, MIDs were seen in most domains; 71.4% patients were responders in "total score." In caregivers, improvements were seen for most domains of the Hemo-Sat_P with a small effect size. Fewer patients missed school when treated with rIX-FP and 94.1% patients maintained their physical activity level.

CONCLUSION

Prophylaxis with rIX-FP led to substantial improvements in HRQoL in paediatric patients and treatment satisfaction in caregivers.

Updates in clinical trial data of extended half-life recombinant factor IX products for the treatment of haemophilia B

Whilst the global prevalence of haemophilia B is less than that of haemophilia A, rapid and remarkable innovations have been made in the development of haemophilia B therapies in the last decade. The most recent developments are the evolution of extended half-life haemophilia B replacement therapies which are designed to reduce the treatment burden associated with prophylactic infusion of factor IX (FIX) to prevent bleeding in haemophilia B participants. Clinical development programmes have culminated in the completion of three phase III studies on extended half-life (EHL) recombinant FIX (rFIX) products and subsequent approval and registration of these in many countries around the world. Current data from the three EHL rFIX clinical studies indicate that these products have acceptable safety profiles with no allergic reactions, thromboembolic phenomena or neutralizing antibodies when given to previously treated adolescent and adults for the prevention of bleeds, for the treatment of bleeds and in the perisurgical haemostasis use. Studies in previously untreated paediatric participants are currently ongoing. The EHL rFIX products have the potential impact to reduce the treatment burden associated with prophylactic infusion of replacement FIX, to treat and prevent bleeds in participants with haemophilia B and to improve the participant's health-related quality of life. The impact of EHL rFIX is likely to be modified by current development of other haemophilia B therapy such as antitissue factor pathway inhibitors and haemophilia B gene therapy. In this review, we aim to provide an update on the safety and efficacy data from the three EHL rFIX clinical studies and to consider their roles in the face of novel haemophilia B therapy currently evolving.

GlycoPEGylated recombinant factor IX for hemophilia B in context

Decisions over hemophilia treatment selection and switching involve balancing many clinical and patient-related factors. The current standard of care for patients with hemophilia B is prophylaxis with plasma-derived or recombinant factor IX (rFIX) concentrates. However, several extended half-life (EHL) rFIX products have recently been developed to improve treatment convenience and clinical outcomes for these patients. Nonacog beta pegol, an rFIX product that combines the FIX protein with a 40 kDa polyethylene glycol moiety, has been evaluated in 115 previously treated patients with hemophilia B (including 25 children) in the paradigm clinical trial program. FIX activity levels and pharmacokinetics were monitored throughout these trials and showed that nonacog beta pegol offers significant pharmacological improvements over standard FIX products. Once-weekly prophylaxis with nonacog beta pegol 40 IU/kg resulted in fewer bleeds in all patients (median annualized bleeding rate of 1.0 across all ages), resolved 90% of target joints, and improved health-related quality of life. No patients developed FIX inhibitors, and there were no thromboembolic events or unexpected safety concerns. Nonacog beta pegol was also safe and effective in the perioperative setting. These findings show that nonacog beta pegol is highly effective, while also offering more convenient dosing than standard FIX products. Nonacog beta pegol represents a significant advance in the current context of treatment for hemophilia B, offering effective management across several treatment modalities and settings, and potentially easing the treatment burden for patients of all ages. Meanwhile, the development of novel treatment strategies, such as gene therapy, anti-tissue factor pathway inhibitor antibodies, and RNA interference therapy, may provide patients with additional therapeutic options, which would require reassessment of the role of EHL products in the future.

The benefits of prophylaxis in patients with hemophilia B

INTRODUCTION

The health benefits of prophylactic dosing regimens for clotting factor therapy in patients with hemophilia include reduced joint damage and improved quality of life; as such, prophylaxis is recommended in treatment guidelines. However, many patients with hemophilia B are treated on demand, and prophylaxis has been utilized less frequently than in hemophilia A. Areas covered: This review discusses the opportunities and evidence for prophylaxis in hemophilia B, in the context of treatment guidelines and with regard to factor IX (FIX) replacement therapies, including long-acting recombinant FIX (rFIX). Expert commentary: Long-acting rFIX concentrates may increase uptake of and adherence to prophylaxis regimens through attainment of higher trough levels with longer dosing intervals. In this new era of hemophilia B treatment, physicians may be able to achieve better clinical outcomes for their patients and reconsider treatment goals. Maintaining higher FIX trough levels will undoubtedly have long-term benefits for patients, such as preserving joint function. The long-acting rFIX concentrates support robust prophylaxis regimens and offer physician's flexibility in treating patients to best suit their needs, whether to enable an active lifestyle, to achieve higher trough levels for better bleed protection, or simply to decrease the burden of treatment by reducing injection frequency.

Assessing patients' acceptance of their medication to reveal unmet needs: results from a large multi-diseases study using a patient online community

Background

Patients with chronic conditions are required to take long-term treatments for their disease itself or to prevent any potential health risks. Measuring patient acceptance of their medication should help to better understand and predict patients’ behavior toward treatment. This study aimed to describe the level of patient acceptance toward various long-term treatments in real life using an online patient community.

Methods

This was an observational, cross-sectional study conducted through the French Carenity platform. All Carenity patient members were invited to complete an online questionnaire including the 25-item ACCEptance by the Patients of their Treatment (ACCEPT©) questionnaire. ACCEPT© measures patient acceptance toward their medication and includes one general acceptance dimension (Acceptance/General) and six treatment-attribute specific dimensions (scores 0–100; lowest to highest acceptance): Acceptance/Medication Inconvenience, Acceptance/Long-term Treatment, Acceptance/Regimen Constraints, Acceptance/Side effects, Acceptance/Effectiveness, and Acceptance/Numerous Medications. Patients included in the analysis were treated adults experiencing any chronic diseases and who responded to at least one ACCEPT© item.

Results

Among the 4193 patients included in the analysis, more than 270 chronic diseases were represented, amidst which 19 included more than 30 patients. Mean ACCEPT© Acceptance/General score for those 19 diseases were 61.2 (SD = 31.9) for type 1 diabetes, 59.8 (SD = 32.3) for asthma, 56.3 (SD = 34.3) for hypertension, 52.0 (SD = 32.2) for chronic obstructive pulmonary disease, 51.7 (SD = 27.0) for epilepsy, 50.1 (SD = 33.1) for bipolar disorder, 49.9 (SD = 33.1) for type 2 diabetes, 48.6 (SD = 31.6) for multiple sclerosis, 46.1 (SD = 34.5) for Crohn’s disease/ulcerative colitis, 44.3 (SD = 31.5) for depression, 42.8 (SD = 31.5) for lupus, 42.3 (SD = 33.0) for arthrosis, 41.8 (SD = 32.6) for Parkinson’s disease, 40.5 (SD = 32.2) for rheumatoid arthritis, 38.6 (SD = 31.7) for breast cancer, 36.4 (SD = 36.4) for myocardial infarction, 35.8 (SD = 32.0) for ankylosing spondylitis, 34.1 (SD = 32.3) for psoriasis, and 33.7 (SD = 31.7) for fibromyalgia.

Conclusions

This first of its kind study enabled ACCEPT© data to be collected in real life for a variety of chronic diseases. These data may help in evaluating and interpreting levels of acceptance in future studies and provide valuable insights about patient priorities and current unmet needs.

Health-Related Quality of Life and Psychological Aspects of Adults With Hemophilia in Iran

Hemophilia causes bleeding that may affect patients’ psychological aspects and quality of life. This study aims to evaluate the impact of psychological aspects and pain on health-related quality of life (HRQoL) in adult patients with hemophilia. This cross-sectional study was conducted on 103 patients with hemophilia. Data were collected using hemophilia-specific quality of life, Depression Anxiety Stress Scales, and pain visual analogue scales. Data were analyzed using correlation coefficients, analysis of covariance, and regression analysis. The results showed that 71.7% of patients with hemophilia experienced pain on the study day. The mean score of HRQoL of patients with hemophilia was 51.09 (standard deviation = 19.37). Moreover, 57.4%, 64.6%, and 44.6% of the patients had mild to severe depression, anxiety, and stress, respectively. In addition, a significant association was observed between HRQoL and depression, anxiety, and severity of pain. In the regression model, 48% of changes in HRQOL were explained by the study variables, with the severity of pain and depression being significant predictors. Therefore, attention should be paid to these aspects to improve patients’ quality of life and psychosocial health.

Nonacog Beta Pegol: A Review in Haemophilia B

Nonacog beta pegol [Refixia® (EU)] is an intravenously-administered, glycoPEGylated recombinant factor IX (FIX), with an extended terminal half-life. It is approved in the EU for the treatment and prophylaxis of bleeding in patients aged ≥ 12 years with haemophilia B. The therapeutic efficacy and safety of nonacog beta pegol was demonstrated in the phase 3 Paradigm trials in previously treated adolescents and adults with haemophilia B. In Paradigm 2, nonacog beta pegol showed good haemostatic effects when treating bleeds on-demand, and reduced annualized bleeding rates when used as a once-weekly prophylaxis. It also improved some health-related quality of life measures in adult patients. The longer-term efficacy of nonacog beta pegol was demonstrated in the open-label extension Paradigm 4 trial. In Paradigm 3, nonacog beta pegol effectively maintained intraoperative and postoperative haemostasis. Nonacog beta pegol was well tolerated in phase 3 clinical trials in patients with haemophilia B, with no evidence of FIX inhibitor formation, allergic reactions or thromboembolic complications. In conclusion, nonacog beta pegol is effective and well tolerated in the on-demand, prophylaxis and perioperative settings in adolescent and adults with haemophilia B. Its extended half-life allows for once-weekly prophylaxis. Therefore, nonacog beta pegol is a useful additional treatment option for patients with haemophilia B.