Progress, and prospects in the therapeutic armamentarium of persons with congenital hemophilia. Defining the place for liver-directed gene therapy

Intensive FVIII replacement in hemophilia patients with hypertrophic synovium: a randomized study

BACKGROUND

Hypertrophic synovium (HS) is a marker of disease activity in persons with hemophilia (PwH). Although some recommendations suggest intensifying prophylaxis in PwH with HS, no validated schedules are available.

OBJECTIVES

We explored the efficacy of intensive factor VIII (FVIII) replacement treatment in PwH with HS.

METHODS

In a randomized, open-label study, PwH with HS were randomized to receive pharmacokinetics-driven prophylaxis targeting a FVIII trough level of 8% to 12% (intensive treatment arm [ITA]) or 3% to 5% (standard treatment arm [STA]). The primary outcome was HS reduction/resolution in the 2 treatment arms.

RESULTS

A total of 39 PwH were randomized to ITA and 36 to STA. During the study, we found a lower annual bleeding rate and a higher rate of annual bleeding rate zero in the ITA than in the STA. HS reduction/resolution was reported in 35.9% of cases in the ITA and 8.4% in the STA. In detail, in the ITA ,10.3% achieved HS reduction and 25.6% complete HS resolution, as compared to 5.6% and 2.8% in the STA. Cox regression showed that ITA was associated with HS reduction/resolution (hazard ratio: 4.75; 95% CI: 1.36-16.57; P = .014) and HS complete resolution (hazard ratio: 10.79; 95% CI: 1.38-84.45; P = .023). The analysis of the 127 joints with HS (54 elbows, 41 knees, and 32 ankles) consistently confirmed similar results.

CONCLUSION

In this randomized study, we found a ∼5-fold higher rate of HS reduction/resolution and a ∼10-fold higher rate of HS resolution in the ITA than in the STA.

Patient Perspective on Disease Burden and Gene Therapy for Hemophilia A and B: The "Haemvolution for Patients" Italian Survey

Hemophilia is a rare X-linked congenital bleeding disorder due to a deficiency of factor VIII (hemophilia A [HA]) or factor IX (hemophilia B [HB]). Replacement and nonreplacement treatments are available but have limitations. Gene therapy (GT) provides an effective, long-term, single-dose treatment option, now approaching clinical practice. This study aimed to understand patient perspectives on GT for HA and HB in Italy using a qualitative questionnaire distributed through Italian patient associations, addressing patient views on daily life, treatments, unmet needs, quality of life (QoL), and GT for hemophilia. In total, 141 participants had HA, and 14 had HB (severe 78.6%). Daily life was most affected by pain and/or joint function limitations (57.5% of participants), high infusion frequency (42.5%), management of breakthrough bleeding episodes (40.3%), and anxiety/fear of severe or sudden bleeding (38.8%). Despite current treatments, about half of the participants experienced three or more annual bleeding episodes. Most participants knew of GT (87.2%) and expected improvements in QoL (60.5%), reduced frequency of current treatments (53.5%), and a permanent cure (49.1%); 46.4% were unaware of its once-off dosage and 46.4% were not concerned about the costs they anticipated to be associated with GT. Although several fears were reported, 25.0% of participants were willing to undergo GT with the support of a multidisciplinary team. This survey provided valuable insight into patient perspectives on hemophilia and GT in Italy. Overall, relevant proportions of patients still experience limitations affecting their daily life. Most were positive about GT and anticipated improvements in their clinical outcomes and QoL.

Awareness of individual goals, preferences, and priorities of persons with severe congenital haemophilia A for a tailored shared decision-making approach to liver-directed gene therapy. A practical guideline

In clinical medicine, shared decision making (SDM) is a well-recognized strategy to enhance engagement of both patients and clinicians in medical decisions. The success of liver-directed gene therapy (GT) to transform severe congenital haemophilia A (HA) from an incurable to a curable disease has launched a shift beyond current standards of treatment. However, GT acceptance remains low in the community of HA persons. We argue for both persons with haemophilia (PWH) and specialists in HA care including clinicians, as needing SDM-oriented educational programs devoted to GT. Here, we provide an ad hoc outline to implement education to SDM and tailor clinician information on GT to individual PWHs. Based on routine key components of SDM: patient priorities; recommendations based on individual risk reduction; adverse effects; drug-drug interactions; alternatives to GT; and ongoing re-assessment of the objectives as risk factors (and individual priorities) change, this approach is finalized to exploit efficacious communication.

Residual burden of liver disease after HCV clearance in hemophilia: a word of caution in the era of gene therapy

Ruling out advanced fibrosis/cirrhosis is mandatory for persons with hemophilia (PWH) who are candidates for gene therapy. However, clinical evaluation and noninvasive tests (NITs) may be inaccurate after hepatitis C virus (HCV) clearance. We conducted a prospective hepatological screening to detect advanced fibrosis/cirrhosis in PWH after HCV clearance. Any risk factor of chronic liver damage was registered by using biochemical data, liver stiffness measurement (LSM), and ultrasound (US). A pre/post-HCV clearance analysis was conducted prospectively in a subgroup of patients who underwent LSM, US, and NITs for fibrosis. We evaluated 119 patients (median age, 53 years; range, 36-87 years) with a previous HCV infection (hemophilia A, n = 108; hemophilia B, n = 11). Ninety-six (81%) presented at least 1 potential risk factor of chronic liver damage. Metabolic risk factors were the most prevalent, with 51 patients (44%) having US steatosis. In 21 patients (18%), clinical, biochemical, liver morphology, and/or LSM were suggestive of advanced fibrosis/cirrhosis. Furthermore, 10 patients (8%) had esophageal varices and 3 (3%) had hepatocellular carcinoma. In 57 patients included in the prospective analysis, LSM and NITs were reduced after HCV clearance (P < .05), but US signs specific of cirrhosis remained unchanged. Overall, 23 of 80 patients (29%) with LSM <10 KPa had at least 1 US sign suggestive of advanced fibrosis/cirrhosis. A similar proportion (18%) was observed for LSM <8 KPa. Overall, risk factors of chronic liver damage are frequent after HCV clearance, but changes in LSM and NITs after clearance may be inaccurate to rule out advanced fibrosis/cirrhosis. A specific diagnostic workup is warranted to evaluate liver health in PWH in the era of gene therapy.

The Arrival of Gene Therapy for Patients with Hemophilia A

Historically, the standard of care for hemophilia A has been intravenous administration of exogenous factor VIII (FVIII), either as prophylaxis or episodically. The development of emicizumab, a humanized bispecific monoclonal antibody mimicking activated FVIII, was a subsequent advance in treatment. However, both exogenous FVIII and emicizumab require repeated and lifelong administration, negatively impacting patient quality of life. A recent breakthrough has been the development of gene therapy. This allows a single intravenous treatment that could result in long-term expression of FVIII, maintenance of steady-state plasma concentrations, and minimization (or possibly elimination) of bleeding episodes for the recipient's lifetime. Several gene therapies have been assessed in clinical trials, with positive outcomes. Valoctocogene roxaparvovec (an adeno-associated viral 5-based therapy encoding human B domain-deleted FVIII) is expected to be the first approved gene therapy in European countries, including Italy, in 2022. Some novel challenges exist including refining patient selection criteria, managing patient expectations, further elucidation of the durability and variability of transgene expression and long-term safety, and the development of standardized 'hub and spoke' centers to optimize and monitor this innovative treatment. Gene therapy represents a paradigm shift, and may become a new reference standard for treating patients with hemophilia A.