SURPASS-ET: phase III study of ropeginterferon alfa-2b versus anagrelide as second-line therapy in essential thrombocythemia

A Phase 3, Randomized, Controlled Trial Evaluating the Efficacy and Safety of Ropeginterferon Alfa-2b in Patients with Moderate COVID-19

INTRODUCTION

Ropeginterferon alfa-2b is a novel mono-pegylated proline-interferon. This clinical study aimed to evaluate its antiviral efficacy of ropeginterferon alfa-2b against SARS-CoV-2 infection.

METHODS

This is a multicenter, randomized, open-label study. Adult patients with confirmed SARS-CoV-2 infection with initial cycle threshold (Ct) value < 30 and symptom onset within 4 days were enrolled. Eligible patients were randomized in a 2:1 ratio to receive a single 250-µg dose of ropeginterferon alfa-2b subcutaneously plus standard of care (SOC) or to receive SOC alone. The primary endpoint was the proportion of patients with a negative RT-PCR result for SARS-CoV-2 or discharged from the hospital before Day 8. Change in clinical status based on the World Health Organization (WHO) clinical progression scale and pulmonary infiltrations through chest radiograph were also evaluated.

RESULTS

A total of 132 patients were enrolled and treated with study medication. Higher percentages of patients who achieved Ct ≥ 30 or were discharged from the hospital were observed on Day 8 and every other time point of assessment, i.e., Days 5, 11, 15, and 22, in the ropeginterferon alfa-2b group compared to the SOC alone group. However, the difference was statistically significant on Day 11 but not on Day 8. The primary endpoint was not met. The ropeginterferon alfa-2b group showed a higher improvement rate in lung infiltration on Day 5 (27.6% vs. 0.0%, p = 0.0087) and a higher improvement rate in WHO clinical progression scores on Day 8 (69.4% vs. 35.3%, p = 0.03) than those in the SOC group. No ropeginterferon alfa-2b-related serious adverse event was observed.

CONCLUSION

Our data show that ropeginterferon alfa-2b with SOC shortened the duration of SARS-CoV-2 shedding compared with SOC alone. In addition, ropeginterferon alfa-2b as an additional therapy could be beneficial by improving lung infiltration.

ROP-ET: a prospective phase III trial investigating the efficacy and safety of ropeginterferon alfa-2b in essential thrombocythemia patients with limited treatment options

Interferon-based therapies, such as ropeginterferon alfa-2b have emerged as promising disease-modifying agents for myeloproliferative neoplasms (MPNs), including essential thrombocythemia (ET). Current ET treatments aim to normalize hematological parameters and reduce the thrombotic risk, but they do not modify the natural history of the disease and hence, have no impact on disease progression. Ropeginterferon alfa-2b (trade name BESREMi®), a novel, monopegylated interferon alfa-2b with an extended administration interval, has demonstrated a robust and sustained efficacy in polycythemia vera (PV) patients. Given the similarities in disease pathophysiology and treatment goals, ropeginterferon alfa-2b holds promise as a treatment option for ET. The ROP-ET trial is a prospective, multicenter, single-arm phase III study that includes patients with ET who are intolerant or resistant to, and/or are ineligible for current therapies, such as hydroxyurea (HU), anagrelide (ANA), busulfan (BUS) and pipobroman, leaving these patients with limited treatment options. The primary endpoint is a composite response of hematologic parameters and disease-related symptoms, according to modified European LeukemiaNet (ELN) criteria. Secondary endpoints include improvements in symptoms and quality of life, molecular response and the safety profile of ropeginterferon alfa-2b. Over a 3-year period the trial assesses longer term outcomes, particularly the effects on allele burden and clinical outcomes, such as disease-related symptoms, vascular events and disease progression. No prospective clinical trial data exist for ropeginterferon alfa-2b in the planned ET study population and this study will provide new findings that may contribute to advancing the treatment landscape for ET patients with limited alternatives. TRIAL REGISTRATION: EU Clinical Trials Register; EudraCT, 2023-505160-12-00; Registered on October 30, 2023.

Essential thrombocythaemia: A contemporary approach with new drugs on the horizon

Essential thrombocythaemia (ET) is a myeloproliferative neoplasm characterized by an increased risk of vascular complications and a tendency to progress to myelofibrosis and acute leukaemia. ET patients have traditionally been stratified into two thrombosis risk categories based on age older than 60 years and a history of thrombosis. More recently, the revised IPSET-thrombosis scoring system, which accounts for the increased risk linked to the JAK2 mutation, has been incorporated into most expert recommendations. However, there is increasing evidence that the term ET encompasses different genomic entities, each with a distinct clinical course and prognosis. Moreover, the effectiveness and toxicity of cytoreductive and anti-platelet treatments differ depending on the molecular genotype. While anti-platelets and conventional cytoreductive agents, mainly hydroxycarbamide (hydroxyurea), anagrelide and pegylated interferon, remain the cornerstone of treatment, recent research has shed light on the effectiveness of novel therapies that may help improve outcomes. This comprehensive review focuses on the evolving landscape of treatment strategies in ET, with an emphasis on the role of molecular profiling in guiding therapeutic decisions. Besides evidence-based management according to revised IPSET-thrombosis stratification, we also provide specific observations for those patients with CALR-, MPL-mutated and triple-negative ET, as well as cases with high-risk mutations.

Effective Management of Polycythemia Vera With Ropeginterferon Alfa-2b Treatment

Background

Polycythemia vera (PV) is a myeloproliferative neoplasm. Ropeginterferon alfa-2b is a new-generation polyethylene glycol-conjugated proline-interferon. It is approved for the treatment of PV at a starting dose of 100 µg (50 µg for patients receiving hydroxyurea (HU)) and dose titrations up to 500 µg by 50 µg increments. The study was aimed at assessing its efficacy and safety at a higher starting dose and simpler intra-patient dose escalation.

Methods

Forty-nine patients with PV having HU intolerance from major hospitals in China were treated biweekly with an initial dose of 250 µg, followed by 350 µg and 500 µg thereafter if tolerated. Complete hematological response (CHR) was assessed every 12 weeks based on the European LeukemiaNet criteria. The primary endpoint was the CHR rate at week 24. The secondary endpoints included CHR rates at weeks 12, 36 and 52, changes of JAK2V617F allelic burden, time to first CHR, and safety assessments.

Results

The CHR rates were 61.2%, 69.4% and 71.4% at weeks 24, 36, and 52, respectively. Mean allele burden of the driver mutation JAK2V617F declined from 58.5% at baseline to 30.1% at 52 weeks. Both CHR and JAK2V617F allele burden reduction showed consistent increases over the 52 weeks of the treatment. Twenty-nine patients (63.0%) achieved partial molecular response (PMR) and two achieved complete molecular response (CMR). The time to CHR was rapid and median time was 5.6 months according to central lab results. The CHRs were durable and median CHR duration time was not reached at week 52. Mean spleen index reduced from 55.6 cm2 at baseline to 50.2 cm2 at week 52. Adverse events (AEs) were mostly mild or moderate. Most common AEs were reversible alanine aminotransferase and aspartate aminotransferase increases, which were not associated with significant elevations in bilirubin levels or jaundice. There were no grade 4 or 5 AEs. Grade 3 AEs were reversible and manageable. Only one AE led to discontinuation. No incidence of thromboembolic events was observed.

Conclusion

The 250-350-500 µg dosing regimen was well tolerated and effectively induced CHR and MR and managed spleen size increase. Our findings demonstrate that ropeginterferon alfa-2b at this dosing regimen can provide an effective management of PV and support using this dosing regimen as a treatment option.

Research progress on the PEGylation of therapeutic proteins and peptides (TPPs)

With the rapid advancement of genetic and protein engineering, proteins and peptides have emerged as promising drug molecules for therapeutic applications. Consequently, there has been a growing interest in the field of chemical modification technology to address challenges associated with their clinical use, including rapid clearance from circulation, immunogenicity, physical and chemical instabilities (such as aggregation, adsorption, deamination, clipping, oxidation, etc.), and enzymatic degradation. Polyethylene glycol (PEG) modification offers an effective solution to these issues due to its favorable properties. This review presents recent progress in the development and application of PEGylated therapeutic proteins and peptides (TPPs). For this purpose, firstly, the physical and chemical properties as well as classification of PEG and its derivatives are described. Subsequently, a detailed summary is provided on the main sites of PEGylated TPPs and the factors that influence their PEGylation. Furthermore, notable instances of PEG-modified TPPs (including antimicrobial peptides (AMPs), interferon, asparaginase and antibodies) are highlighted. Finally, we propose the chemical modification of TPPs with PEG, followed by an analysis of the current development status and future prospects of PEGylated TPPs. This work provides a comprehensive literature review in this promising field while facilitating researchers in utilizing PEG polymers to modify TPPs for disease treatment.

Interferons in the treatment of myeloproliferative neoplasms

Interferons are cytokines with immunomodulatory properties and disease-modifying effects that have been used to treat myeloproliferative neoplasms (MPNs) for more than 35 years. The initial use of interferons was limited due to difficulties with administration and a significant toxicity profile. Many of these shortcomings were addressed by covalently binding polyethylene glycol to the interferon structure, which increases the stability, prolongs activity, and reduces immunogenicity of the molecule. In the current therapeutic landscape, pegylated interferons are recommended for use in the treatment of polycythemia vera, essential thrombocythemia, and primary myelofibrosis. We review recent efficacy, molecular response, and safety data for the two available pegylated interferons, peginterferon alfa-2a (Pegasys) and ropeginterferon alfa-2b-njft (BESREMi). The practical management of interferon-based therapies is discussed, along with our opinions on whether to and how to switch from hydroxyurea to one of these therapies. Key topics and questions related to use of interferons, such as their safety and tolerability, the significance of variant allele frequency, advantages of early treatment, and what the future of interferon therapy may look like, will be examined. Pegylated interferons represent an important therapeutic option for patients with MPNs; however, more research is still required to further refine interferon therapy.

Study Protocol of a Randomized Controlled Clinical Trial to Evaluate the Efficacy and Safety of Ropeginterferon Alfa-2b in COVID-19 Patients with Comorbidities

INTRODUCTION

Ropeginterferon alfa-2b represents a new-generation PEGylated interferon. It is approved for the treatment of polycythemia vera and shows promising anti-SARS-CoV-2 activities.

OBJECTIVE

This clinical study aims to evaluate the efficacy and safety of ropeginterferon alfa-2b in patients with coronavirus disease 2019 (COVID-19) and comorbidities.

METHODS

The randomized controlled study is designed to enroll adult patients with COVID-19 infection and comorbidities. Patients are non-responders to anti-SARS-CoV-2 drugs or not suitable to receive them. Comorbidities include hematologic cancer, solid tumor, and well-controlled autoimmune disease. Non-responders to anti-SARS-CoV-2 drugs are defined as having received treatment but have a Ct value < 30 at 14 days after symptom onset. Patients are randomized in a 1:1 ratio to receive ropeginterferon alfa-2b at 250 μg plus standard of care (SOC) or SOC alone. SARS-CoV-2 antigen test will be conducted at day 15 and day 29 visits to determine whether to administer additional ropeginterferon alfa-2b doses. Patients who are positive on the antigen test on days 15 and 29 will receive the second and third doses of ropeginterferon alfa-2b at 350 μg and 500 μg, respectively. Patients with a negative antigen test but a Ct value < 30 by reverse transcription polymerase chain reaction (RT-PCR) at days 15 and 29 are also administered the second (350 μg) and third (500 μg) doses. Patients at high risk of COVID-19 rebound/relapse, e.g., immunocompromised patients, will be given additional ropeginterferon alfa-2b doses even if the Ct is ≥ 30. Approximately 60 patients will be enrolled.

PLANNED OUTCOMES

The primary outcome is to compare the time from randomization to the achievement of Ct value ≥ 30 by RT-PCR between ropeginterferon alfa-2b and control groups. Our previous studies have shown safety and promising anti-SARS-CoV-2 activities in patients with moderate or severe COVID-19. This study will provide valuable data in patients with COVID-19 and comorbidities, for whom safe and effective treatment is urgently needed.

TRIAL REGISTRATION NUMBER

This trial is registered at ClinicalTrials.gov (Identifier NCT05808322).

A therapeutic dose and its pharmacokinetics of ropeginterferon Alfa-2b for hepatitis C treatment

AIM

Ropeginterferon alfa-2b is a novel mono-pegylated proline-interferon. Its biweekly dosing schema has demonstrated tolerability and clinical efficacy for treating chronic hepatitis in previous clinical studies. This trial evaluates the pharmacokinetics of 400 μg ropeginterferon alfa-2b in patients with chronic hepatitis C virus (HCV) and provides the data to support the clinical utility of ropeginterferon alfa-2b at 400 μg.

METHODS

Seventeen patients with chronic HCV genotype 2 were enrolled to receive a single injection of 400 μg ropeginterferon alfa-2b plus 14-day treatment of ribavirin. Pharmacokinetics, safety, and HCV RNA reduction/clearance were assessed.

RESULTS

Tmax was 154.003 h and T1/2 was 114.273 h. The Cmax was 29.823 ng mL-1. AUClast was 9364.292 h∗ng mL-1 and AUCinf was 11084.317 h∗ng mL-1. All adverse events were mild or moderate, and there were no serious adverse events. A 1000-fold reduction in the geometric mean of HCV RNA was observed 14 d after the single injection of ropeginterferon alfa-2b. Two patients achieved clearance of HCV RNA, and the other five patients had HCV RNA levels lower than 200 IU mL-1.

CONCLUSION

Ropeginterferon alfa-2b at 400 μg led to PK exposures associated with safety and notable clinical activity in patients with chronic HCV. This study suggests that ropeginterferon alfa-2b at 400 μg is an acceptable dosing regimen for treating chronic HCV and also provides supporting data for the clinical use of ropeginterferon alfa-2b at a higher starting dose for other indications.

Sequential Therapy with Ropeginterferon Alfa-2b and Anti-Programmed Cell Death 1 Antibody for Inhibiting the Recurrence of Hepatitis B-Related Hepatocellular Carcinoma: From Animal Modeling to Phase I Clinical Results

Hepatocellular carcinoma (HCC) usually recurs after curative surgical resection. Currently, no approved adjuvant therapy has been shown to reduce HCC recurrence rates. In this study, the in vivo effect of sequential combination treatment with recombinant mouse interferon-alpha (rmIFN-α) and an anti-mouse-PD1 antibody on hepatitis B virus (HBV) clearance in mice was evaluated. A Phase I clinical trial was then conducted to assess the safety, tolerability, and inhibitory activity of sequential therapy with ropeginterferon alfa-2b and nivolumab in patients with HCC recurrence who underwent curative surgery for HBV-related HCC. The animal modeling study showed that HBV suppression was significantly greater with the rmIFN-α and anti-PD1 sequential combination treatment in comparison with sole treatment with rmIFN-α or anti-PD1. In the Phase I study, eleven patients completed the sequential therapy with ropeginterferon alfa-2b every two weeks for six doses at 450 µg, followed by three doses of nivolumab every two weeks up to 0.75 mg/kg. A notable decrease in or clearance of HBV surface antigen was observed in two patients. The dose-limiting toxicity of grade 3 alanine transaminase and aspartate aminotransferase increases was observed in one patient. The maximum tolerated dose was then determined. To date, no HCC recurrence has been observed. The treatment modality was well tolerated. These data support the further clinical development of sequential combination therapy as a post-surgery prophylactic measure against the recurrence of HBV-related HCC.

Effectiveness of Ropeginterferon Alfa-2B in High-Risk Patients with Philadelphia Chromosome Negative Myeloproliferative Neoplasms- Evaluation of Clinicohaematologic Response, and Safety Profile: Single Centre Experience

Background: Treatment of Philadelphia chromosome negative myeloproliferative neoplasms (Ph - MPNs) requires individualized approach depending on multiple factors. Novel pegylated Interferon (IFN) formulations have become an attractive therapeutic option in young Ph- MPN patients associated with better patient compliance. Methods: In this retrospective observational study a total of 16 high-risk Ph- MPN patients treated off-label with ropeginterferon alfa-2b given twice monthly, were included. Median follow-up was 24 months. High-risk patients were defined using the IPSET score. Response to treatment was evaluated using ELN, IWG-MET EUMNET standardized criteria and occurrence of side effects was documented. Results: 11 patients were female (68.8%) and 5 male (31.2%); average age at diagnosis was 36 years (17-51); 12 patients (75%) had ET, one (6.2%) PV and three (18.8%) hypercellular phase of PMF. JAK2V617F mutation was detected in 10 patients (62.5%), CALR in three (18.8%), and three (18.7%) were triple-negative cases. In 7 patients (43.7%), ropeginterferon alfa-2b was used in first-line, and 9 (56.3%) were previously treated with HU and/or standard IFN. Among initially ropeginterferon alfa-2b treated patients, complete haematological response was observed in 4/7 (57.1%), partial in 2/7 (28.6%) and suboptimal in one (14.3%). Complete haematological response was observed in 8/9 (88.9%) among previously treated patients. Average time to blood count normalization was 8 weeks, at a dose ranging between 100mcg and 300mcg. Side effects were observed in one patient (6.2%). Conclusion: Our experience is in support of previous studies regarding ropeginterferon alfa-2b efficacy and safety profile in the treatment of young patients with Ph- MPNs.

Long-acting interferon: pioneering disease modification of myeloproliferative neoplasms

Myeloproliferative neoplasms (MPNs) are clonal disorders of hematopoietic stem cells. The malignant clones produce cytokines that drive self-perpetuating inflammatory responses and tend to transform into more aggressive clones, leading to disease progression. The progression of MPNs follows a biological sequence from the early phases of malignancy, polycythemia vera, and essential thrombocythemia, to advanced myelofibrosis and leukemic transformation. To date, the treatment of MPNs has focused on preventing thrombosis by decreasing blood cell counts and relieving disease-related symptoms. However, interferon (IFN) has been used to treat MPNs because of its ability to attack cancer cells directly and modulate the immune system. IFN also has the potential to modulate diseases by inhibiting JAK2 mutations, and recent studies have demonstrated clinical and molecular improvements. Long-acting IFN is administered less frequently and has fewer adverse effects than conventional IFN. The current state of research on long-acting IFN in patients with MPNs is discussed, along with future directions.

Diagnosis- and Prognosis-Related Gene Alterations in BCR::ABL1-Negative Myeloproliferative Neoplasms

BCR::ABL1-negative myeloproliferative neoplasms (MPNs) are a group of hematopoietic malignancies in which somatic mutations are acquired in hematopoietic stem/progenitor cells, resulting in an abnormal increase in blood cells in peripheral blood and fibrosis in bone marrow. Mutations in JAK2, MPL, and CALR are frequently found in BCR::ABL1-negative MPNs, and detecting typical mutations in these three genes has become essential for the diagnosis of BCR::ABL1-negative MPNs. Furthermore, comprehensive gene mutation and expression analyses performed using massively parallel sequencing have identified gene mutations associated with the prognosis of BCR::ABL1-negative MPNs such as ASXL1, EZH2, IDH1/2, SRSF2, and U2AF1. Furthermore, single-cell analyses have partially elucidated the effect of the order of mutation acquisition on the phenotype of BCR::ABL1-negative MPNs and the mechanism of the pathogenesis of BCR::ABL1-negative MPNs. Recently, specific CREB3L1 overexpression has been identified in megakaryocytes and platelets in BCR::ABL1-negative MPNs, which may be promising for the development of diagnostic applications. In this review, we describe the genetic mutations found in BCR::ABL1-negative MPNs, including the results of analyses conducted by our group.

A new dosing regimen of ropeginterferon alfa-2b is highly effective and tolerable: findings from a phase 2 study in Chinese patients with polycythemia vera

Ropeginterferon alfa-2b represents a new-generation pegylated interferon-based therapy and is administered every 2-4 weeks. It is approved for polycythemia vera (PV) treatment in the United States and Europe with a starting dose of 100 µg (50 µg for patients receiving hydoxyurea) and intra-patient dose titrations up to 500 µg at 50 µg increments, which took approximately 20 or more weeks to reach a plateau dose level. This study aimed to assess ropeginterferon alfa-2b at an alternative dosing regimen with a higher starting dose and quicker intra-patient dose titrations, i.e., the 250-350-500 μg schema, in 49 Chinese patients with PV with resistance or intolerance to hydroxyurea. The primary endpoint of the complete hematologic response rate at treatment weak 24 was 61.2%, which was notably higher than 43.1% at 12 months with the approved dosing schema. The JAK2^V617F allele burden decreased from baseline to week 24 (17.8% ± 18.0%), with one patient achieving a complete molecular response. Ropeginterferon alfa-2b was well-tolerated and most adverse events (AEs) were mild or moderate. Common AEs included alanine aminotransferase and aspartate aminotransferase increases mostly at grade 1 or 2 levels. Patients did not present with jaundice or significant bilirubin level increase. No grade 4 or 5 AEs occurred. Seven patients (14.3%) experienced reversible, drug-related grade 3 AEs. No AEs led to treatment discontinuation. Ropeginterferon alfa-2b at the 250-350-500 μg regimen is highly effective and well-tolerated and can help patients achieve greater and rapid complete hematologic and molecular responses.Clinical Trial Registration: This trial is registered at ClinicalTrials.gov (Identifier: NCT05485948) and in China (China National Medical Products Administration Registration Number: CTR20211664).

A phase II trial to assess the efficacy and safety of ropeginterferon α-2b in Chinese patients with polycythemia vera

Ropeginterferon α-2b is a mono-PEGylated proline-interferon for the treatment of polycythemia vera (PV). This drug is used biweekly with a starting dose of 100 μg (50 μg if patients receiving hydroxyurea) and 50 μg increments up to a maximum dose of 500 μg. Increasing evidence indicates that patients can tolerate higher starting doses of ropeginterferon α-2b. This phase II trial utilizes 250 μg as the starting dose, 350 μg at week 2 and 500 μg at week 4 as the target dose. Doses can be adjusted according to tolerability. This study assesses the safety, efficacy and molecular response of ropeginterferon α-2b in Chinese patients with PV utilizing the 250-350-500 μg dosing schema. This study will be used to support the application of a biologics license for PV treatment in China.

Evaluating ropeginterferon alfa-2b for the treatment of adults with polycythemia vera

INTRODUCTION

Interferons (IFNs) have been used for decades to treat polycythemia vera (PV). Single-arm clinical trials assessing IFN in PV patients demonstrated high hematological and molecular response rates, indicating potential disease-modifying activity of IFN. However, discontinuation rates of IFNs have been rather high due to frequent treatment-related side-effects.

AREAS COVERED

Ropeginterferon alfa-2b (ROPEG) is a monopegylated IFN consisting of a single isoform, which differentiates it from previous IFNs with respect to tolerability and dosing frequency. ROPEG has improved pharmacokinetic and pharmacodynamic properties, which allow extended dosing every 2 weeks and monthly administration during maintenance phase. This review covers ROPEG's pharmacokinetic and pharmacodynamic properties, presents results of randomized clinical trials (RCT) that evaluated ROPEG in the treatment of PV patients, and discusses contemporary findings regarding the potential disease-modifying activity of ROPEG.

EXPERT OPINION

RCT have demonstrated high rates of hematological and molecular responses in PV patients treated with ROPEG, irrespective of thrombotic risk. Drug discontinuation rates were generally low. However, even though RCT captured the most important surrogate endpoints of thrombotic risk and disease progression in PV, they were not statistically powered to fully determine whether therapeutic intervention with ROPEG indeed has a direct positive effect on these important clinical outcomes.

An alternative dosing strategy for ropeginterferon alfa-2b may help improve outcomes in myeloproliferative neoplasms: An overview of previous and ongoing studies with perspectives on the future

Ropeginterferon alfa-2b is a novel, long-acting mono-pegylated proline-IFN-alpha-2b approved for treatment of polycythemia vera in adults, regardless of thrombotic risk level or treatment history. Clinical trial data indicate the dose and titration of ropeginterferon alfa-2b is safe and effective. However, additional studies may provide rationale for an amended, higher initial dosage and rapid titration. This article is an overview of current and upcoming studies of ropeginterferon alfa-2b in myeloproliferative neoplasms that support the exploration of an amended dosing scheme in order to optimize patient tolerability and efficacy outcomes.

An anti-cancer surveillance by the interplay between interferon-beta and retinoblastoma protein RB1

Interferon-beta (IFN-β), an extracellular cytokine that initiates signaling pathways for gene regulation, has been demonstrated to function as a tumor suppressor protein through lentiviral gene transduction. In this article, I review the relevant previous works and propose a cell cycle-based, tumor suppressor protein-mediated mechanism of anti-cancer surveillance. IFN-β induces a tumor cell cycle alteration that leads to S phase accumulation, senescence entry, and a loss of tumorigenicity in solid tumor cells. IFN-β does not show a significant cell cycle effect in their normal counterparts. Retinoblastoma protein RB1, another tumor suppressor protein, tightly controls the cell cycle and differentiation of normal cells, preventing them from being significantly impacted by the IFN-β effect. The interplay between IFN-β and RB1 acts as a mechanism of cell cycle-based, tumor suppressor protein-mediated anti-cancer surveillance that can selectively suppress solid tumor or proliferating transformed cells from the loss of control leading to cancer. This mechanism has important implications for the treatment of solid tumors.

Challenges of diagnosing and managing pre-fibrotic myelofibrosis: A case-based and practical approach

Pre-Fibrotic Myelofibrosis is a frequently under-recognised entity that has distinct features separate to those of both Essential Thrombocythaemia and overt Primary Myelofibrosis. Misdiagnosis is relatively common due to subtle differences in bone marrow trephine morphology and multidisciplinary approaches are required. The clinical phenotype and disease course is heterogeneous and hence management approaches tend to vary widely. Although patients may initially be asymptomatic, disease-related complications can include troublesome symptom burdens, increased incidence of both arterial and venous thromboses, haemorrhage, anaemia and an inherent risk of disease evolution to either overt myelofibrosis or blastic phase disease. Specific prognostic tools with high discriminatory power are lacking. Within this review we use case-based approaches to review the current literature, highlight challenges in both diagnostics and disease management and suggest contemporary approaches to improve patient outcomes.