Tertiary prophylaxis in adults: is there a rationale?

Cost-effectiveness analysis of low-dose prophylaxis versus on-demand treatment for moderate-to-severe hemophilia A in India

AIM

Hemophilia A (HA) is an inherited bleeding disorder caused by a deficiency of clotting factor VIII in the blood. In resource-limited settings like India, affordability is a significant challenge in managing patients with severe HA. This study aims to assess the cost-effectiveness of intermediate-dose prophylaxis versus on-demand factor therapy in adult and pediatric populations with moderate-to-severe congenital HA without inhibitors in India.

METHOD

We conducted a prospective cost-effectiveness analysis from a societal perspective, categorizing patients into a base state and a joint disease state (patients with Hemophilia suffering extensive bleeds leading to chronic joint disease). Using targeted literature search and primary market research, we developed a Markov model measuring the total cost of Hemophilia treatment and health outcomes, including life-years (LYs), quality-adjusted life-years (QALYs), incremental cost-utility ratio (ICUR), and incremental cost-effectiveness ratio (ICER). The model extended over a lifetime horizon of 70 years with a one-year cycle length. Sensitivity analyses assessed study robustness.

RESULTS

Low-dose prophylactic therapy was cost-effective for adults (>18 years) and pediatric populations (<18 years), yielding better health outcomes (adults: 0.15 LYs and 2.43 QALYs gained; pediatric: 0.40 LYs and 3.12 QALYs gained). Intermediate-dose prophylaxis showed positive net monetary benefits in terms of Quality-Adjusted Life Years (QALYs) for both adult and pediatric populations, with dominant ICER and ICUR values in both cases.

CONCLUSION

Using intermediate-dose prophylactic factor VIII therapy is a cost-effective approach that improves clinical outcomes compared to on-demand therapy in the Indian adult and pediatric HA populations without inhibitors.

Trends of outcomes and healthcare utilization following orthopaedic procedures in adults with haemophilia: A 3-decade retrospective review

INTRODUCTION

Haemophilic arthropathy is a serious complication of haemophilia often requiring surgical intervention. It is unclear whether advances in comprehensive care are associated with a reduction in orthopaedic interventions and peri-procedural resource utilization.

AIM

To determine temporal patterns of orthopaedic interventions in persons with haemophilia (PWH), and evaluate changes in healthcare utilization and outcomes.

METHODS

In this Canadian multicentre retrospective cohort study, adult PWH from Northern Alberta and British Columbia who underwent orthopaedic procedures (1990-2018) were included. Temporal changes in the type of procedures, length of stay (LOS), factor utilization and outcomes were examined.

RESULTS

Sixty-five patients (78% haemophilia A) underwent 102 surgeries at a median age of 46.3. Of the 46 severe PWH, 28 (61%) were on prophylaxis at time of surgery. The proportion of total knee arthroplasties (TKA) declined over time (56% 1990-1999, 51% 2000-2009, 27% 2010-2018), with a concomitant rise in ankle arthrodesis (0% 1990-1999, 18% 2000-2009, 27% 2010-2018). Over time, PWH underwent orthopaedic procedures at an older age (P = .02). There was a significant reduction in perioperative factor VIII utilization (P = .003) and median LOS (P < .0001). Major bleeds, prosthetic joint infections and thrombosis were not observed in the last decade.

CONCLUSION

In the last three decades, there was a decline in the proportion of TKA, likely reflecting the impact of widespread use of tertiary prophylaxis. However, ankle arthrodesis rates increased, suggesting that higher trough levels may be required to prevent ankle arthropathy. We observed a significant reduction in LOS and factor utilization, reflecting improvements in perioperative management.

Current therapeutic approaches in the management of hemophilia-a consensus view by the Romanian Society of Hematology

Hemophilia A (HA) and hemophilia B (HB) are rare disorders, being caused by the total lack or under-expression of two factors from the coagulation cascade coded by genes of the X chromosome. Thus, in hemophilic patients, the blood does not clot properly. This results in spontaneous bleeding episodes after an injury or surgical intervention. A patient-centered regimen is considered optimal. Age, pharmacokinetics, bleeding phenotype, joint status, adherence, physical activity, personal goals are all factors that should be considered when individualizing therapy. In the past 10 years, many innovations in the diagnostic and treatment options were presented as being either approved or in development, thus helping clinicians to improve the standard-of-care for patients with hemophilia. Recombinant factors still remain the standard of care in hemophilia, however they pose a challenge to treatment adherence because they have short half-life, which where the extended half-life (EHL) factors come with the solution, increasing the half-life to 96 hours. Gene therapies have a promising future with proven beneficial effects in clinical trials. We present and critically analyze in the current manuscript the pros and cons of all the major discoveries in the diagnosis and treatment of HA and HB, as well as identify key areas of hemophilia research where improvements are needed.

Clinical phenotype of severe and moderate haemophilia: Who should receive prophylaxis and what is the target trough level?

INTRODUCTION

One of the most often stated tenets of haemophilia care is that prophylaxis converts a person from a severe to a moderate phenotype. In this review, we argue that this is not an accurate assumption and that people on prophylaxis predominantly have factor VIII/IX levels in the mild range.

MODERATE HAEMOPHILIA AND PROPHYLAXIS

People with moderate haemophilia, who are treating with on-demand regimens, experience joint bleeds and often develop significant arthropathy. This is especially true for people with a baseline level of 1-3 IU/dl, as first reported 55 years ago, and confirmed in more recent studies. Evidence is emerging suggesting that people with severe haemophilia who are using prophylaxis have better musculoskeletal outcomes than people with moderate haemophilia treated episodically.

TROUGH LEVELS

The debate around the optimum trough level whilst on prophylaxis is ongoing. It is not appropriate to extrapolate information about baseline levels to recommendations about target trough levels on prophylaxis because these are different situations. Studies are emerging that support higher target trough levels than previously used, but in spite of this, the aim of achieving zero bleeds remains elusive with both factor replacement and non-replacement therapies.

CONCLUSIONS

We recommend that people with moderate haemophilia, especially those with a baseline of 1-3 IU/dl, should be offered prophylaxis based on the same criteria as people with severe haemophilia. Trough levels should be maintained above 3 IU/dl or higher if a level of 3 IU/dl does not control breakthrough bleeding and prophylaxis should be tailored to the bleeding phenotype. This advice is in line with recently published guidelines from the World Federation of Haemophilia and the UK Haemophilia Centre Doctors' Organisation.

Long-term analysis of the benefit of prophylaxis for adult patients with severe or moderate haemophilia A

INTRODUCTION

Prophylaxis with factor VIII (FVIII) concentrates in children with haemophilia A (HA) is current standard of care. The benefit of prophylactic treatment for adult HA patients is not commonly accepted.

AIM

To investigate the benefit of prophylaxis over on-demand treatment in adult and elderly patients with severe or non-severe HA in a real-life setting.

METHODS

Data from 163 patients comprising 1202 patient-years were evaluated for 7.5 (±5.3) years. The effects on the annual bleeding rate (ABR, including spontaneous and traumatic bleeds) of treatment with a plasma-derived FVIII concentrate, the patient's age and disease severity were investigated. The effect of changing the treatment from on demand to continuous prophylaxis on the patients' ABRs was further analysed.

RESULTS

Prophylaxis had the greatest effect on the ABRs of patients of any age with severe or non-severe HA. The difference in ABR of all patients treated on demand (median 31.4; interquartile range (IQR) 27.6; N = 83) compared with those treated prophylactically (median 1.3; IQR 3.6; N = 122) was statistically significant (P < .05), even for patients with non-severe HA (median 8.4; IQR 15.5; N = 11) vs median 1.5; IQR 4.2 (N = 17), P < .05). Patients, aged up to 88 years, switching from on demand to continuous prophylaxis showed the lowest median ABR (1.1; N = 51) after their regimen change.

CONCLUSION

Any (even low-frequency) prophylaxis results in lower ABR than on-demand treatment. Patients switching to prophylaxis benefitted the most, irrespective of age or HA severity. Prophylactic treatment-even tertiary-is the regimen of choice for patients of any age, including elderly patients, with severe or non-severe HA.

Patient powered prophylaxis: A 12-month study of individualized prophylaxis in adults with severe haemophilia A

INTRODUCTION

Adults with severe haemophilia A (SHA) may experience breakthrough bleeds despite standard weight-based FVIII prophylaxis three times weekly. Individualized prophylaxis has evolved to optimize patient outcomes.

AIMS

This study aimed to evaluate the impact of a standardized approach to individualized prophylaxis on annualized bleeding rates (ABR), factor utilization, physical activity and quality of life in adults with SHA.

METHODS

In this prospective cohort study, patients with baseline FVIII:C <2% and ABR >3 on weight-based prophylaxis received a standardized approach to individualized prophylaxis. Changes in ABR, annualized FVIII consumption and adherence from the 12-month prestudy and 12-month intervention period were compared. Changes in Haemo-QoL-A total score, Physical Functioning (PF) subscale and physical activity level measured by accelerometry were also examined.

RESULTS

Eighteen patients participated (median age 26 years). Individualized prophylaxis decreased total bleeds in the population by 69% and traumatic bleeds by 73%. The median ABR decreased from 7.5 to 2 (P<.001). Annualized factor consumption increased by 7.3%, as a result of 66% reduction in factor utilization for treatment of bleeds and 25% increase in factor utilization for prophylaxis. Adherence scores for frequency and dosing did not change. There was a significant increase in the Haemo-QoL-A total score (P=.02) and PF score (P=.01) from baseline to 4 months but no change in physical activity.

CONCLUSION

Patients with SHA who switched from standard to individualized prophylaxis show reduced ABR and increased FVIII consumption, and also improved their health-related quality of life. The mechanism is independent of adherence to prescribed prophylactic regimen.

Treatment and Prevention of Bleeds in Haemophilia Patients with Inhibitors to Factor VIII/IX

The development of alloantibodies neutralising therapeutically administered factor (F) VIII/IX (inhibitors) is currently the most severe complication of the treatment of haemophilia. When persistent and at a high titre, inhibitors preclude the standard replacement treatment with FVIII/FIX concentrates, making patients’ management challenging. Indeed, the efficacy of bypassing agents, i.e., activated prothrombin complex concentrates (aPCC) and recombinant activated factor VII (rFVIIa), needed to overcome the haemostatic interference of the inhibitor, is not comparable to that of factor concentrates. In addition, the therapeutical response is unpredictable, with a relevant inter-individual and even intra-individual variability, and no laboratory assay is validated to monitor the efficacy and safety of the treatment. As a result, inhibitor patients have a worse joint status and quality of life compared to inhibitor-free subjects and the eradication of the inhibitor by immune tolerance induction is the preeminent therapeutic goal, particularly in children. However, over the last decades, treatment with bypassing agents has been optimised, allowing home treatment and the individualisation of regimens aimed at improving clinical outcomes. In this respect, a growing body of evidence supports the efficacy of prophylaxis with both bypassing agents in reducing bleeding rates and improving the quality of life, although the impact on long-term outcomes (in particular on preventing/reducing joint deterioration) is still unknown. This review offers an update on the current knowledge and practice of the use of bypassing agents in haemophiliacs with inhibitors, as well as on debated issues and unmet needs in this challenging setting.

Adult severe haemophilia A patients under long-term prophylaxis with factor VIII in routine clinical practice

There is no clear consensus on the best practice for long-term prophylaxis in adults with severe haemophilia A. This is a single-centre prospective case series study. We describe here the demographic data, type and reason of prophylaxis in adult patients (>18 years old) with severe (<1%) haemophilia A, treated in our centre from 2006 to 2013. Prophylaxis was tailored according to pharmacokinetic studies and posterior factor VIII (FVIII) trough level adjustment. We analysed FVIII consumption, bleeding rate, adherence and adverse events in this group of patients. In adult patients who initiated long-term prophylaxis during this period, we compared FVIII consumption and bleeding rate with the previous on-demand period. We analysed data from 18 patients. Median annual FVIII consumption was 2374.2 IU/kg/year. Among the patients receiving tertiary prophylaxis, initiated from 2006 onwards, the annual FVIII consumption was 2557.8 vs. 1696.8 IU/kg per year during the on-demand period (P = 0.312). In this group of patients, there was a decrease in annual bleeding events of 88.3% during prophylaxis compared with the on-demand therapy (P < 0.0001). A high adherence to prophylaxis was observed (84%). No cases of anaphylaxis or symptomatic thromboembolic events were recorded. In adult severe haemophilia A patients, the type of and reason to indicate long-term prophylaxis are diverse nowadays. FVIII consumption varies depending on the justification of prophylaxis. The observations reported provide further support for the efficacy of long-term prophylaxis in adult haemophilia A patients.

How I use bypassing therapy for prophylaxis in patients with hemophilia A and inhibitors

Inhibitor development poses a significant challenge in the management of hemophilia because once an inhibitor is present, bleeding episodes can no longer be treated with standard clotting factor replacement therapy. Consequently, patients with inhibitors are at increased risk for difficult-to-control bleeding and complications, particularly arthropathy and physical disability. Three clinical trials in patients with inhibitors have demonstrated that prophylaxis with a bypassing agent reduces joint and other types of bleeding and improves health-related quality of life compared with on-demand bypassing therapy. In hemophilia patients without inhibitors, the initiation of prophylaxis with factor (F) VIII or FIX prior to the onset of recurrent hemarthroses can prevent the development of joint disease. Whether this is also true for bypassing agent prophylaxis remains to be determined.

Benefits of prophylaxis versus on-demand treatment in adolescents and adults with severe haemophilia A: the POTTER study

Rigorous evidence is lacking on long-term outcomes of factor VIII (FVIII) prophylaxis initiated in adolescent or adult patients with severe haemophilia A. The prospective, open-label Prophylaxis versus On-demand Therapy Through Economic Report (POTTER) study (ClinicalTrials.gov NCT01159587) compared long-term late secondary prophylaxis (recombinant FVIII-FS 20-30 IU/kg thrice weekly) with on-demand treatment in patients aged 12 to 55 years with severe haemophilia A. The annual number of joint bleeding episodes (primary endpoint), total bleeding episodes, orthopaedic and radiologic (Pettersson) scores, health-related quality of life (HRQoL), pharmacoeconomic impact, and safety were evaluated over a > 5-year period (2004-2010). Fifty-eight patients were enrolled at 11 centres in Italy; 53 (27 prophylaxis, 26 on demand) were evaluated and stratified into 2 age subgroups (12-25 and 26-55 years). Patients receiving prophylaxis experienced a significantly lower number of joint bleeding episodes vs the on-demand group (annualised bleeding rate, 1.97 vs 16.80 and 2.46 vs 16.71 in younger and older patients, respectively; p=0.0043). Results were similar for total bleeding episodes. Prophylaxis was associated with significantly fewer target joints (p< 0.001), better orthopaedic (p=0.0019) and Pettersson (p=0.0177) scores, better HRQoL, and fewer days of everyday activities lost (p< 0.0001) but required significantly higher FVIII product consumption. The POTTER study is the first prospective, controlled trial documenting long-term benefits of late secondary prophylaxis in adolescents and adults with severe haemophilia A. The benefits of reduced bleeding frequency, improved joint status, and HRQoL may offset the higher FVIII consumption and costs.

A new recombinant factor VIII: from genetics to clinical use

Advances in recombinant technology and knowledge about coagulation factor VIII (FVIII) are building a platform for new therapeutic options in patients with hemophilia A. The development of turoctocog alfa, a novel, high-purity, third-generation, B-domain truncated recombinant FVIII, has been produced and formulated without the use of animal-derived or human serum-derived components, in the wake of understanding of the new biochemical characteristics of FVIII, namely its protein structure, and glycosylation and sulfating patterns. Culture conditions and a five-step purification process have been developed to optimize the safety of turoctocog alfa. The results of two pilot clinical trials using turoctocog alfa confirmed high safety levels, with no patient developing inhibitors during the period of observation. The purpose of this review is to describe briefly the molecular and biological properties of turoctocog alfa, together with details of its clinical development, with emphasis on the needs of patients with hemophilia A.

Factor VIII therapy for hemophilia A: current and future issues

Hemophilia A is a congenital, recessive, X-linked bleeding disorder that is managed with infusions of plasma-derived or recombinant factor (F) VIII. The primary considerations in FVIII replacement therapy today are the: 1) immunogenicity of FVIII concentrates, 2) role of longer-acting FVIII products, 3) prophylactic use of FVIII in children and adults with severe hemophilia A, and 4) affordability and availability of FVIII products. Improving patient outcomes by increasing the use of FVIII prophylaxis, preventing or eliminating FVIII inhibitors, and expanding access to FVIII concentrates in developing countries are the major challenges confronting clinicians who care for patients with hemophilia A.