Barriers to gene therapy, understanding the concerns people with haemophilia have: an exigency sub-study

BACKGROUND

Gene therapy has the potential to offer people with haemophilia (PwH) a life free from bleeding and the burden posed by current treatment regimens. To date, gene therapy has only been available in clinical trial settings, to PwH without pre-existing or historical factor inhibitors, significant concomitant liver damage or pre-existing neutralising antibodies to the adeno-associated viruses used to deliver the therapy. Thus, most PwH treated at centres not currently involved in gene therapy trials, either as a referral/follow-up centre or as a dosing centre, have been unable to access the therapy. This Exigency sub-study aims to gain a greater understanding of the opinions of PwH in the United Kingdom who have not had access to gene therapy: asking what they understand, what concerns they have, and whether they perceive any barriers preventing their access to gene therapy.

RESULTS

Twenty-three PwH were approached; 14 consented, and one withdrew prior to interview. The mean age of the participants was 35.7 years (range 25-74 years). Eleven had haemophilia A and two haemophilia B. Two were treated with standard half-life factor products, five with extended half-life products, five with a FVIII mimetic and one with a clinical trial product. One family member (a participant's partner) was also interviewed. The participants identified four barriers to gene therapy: concerns about the process of gene therapy (Expectations), uncertainty about the results (outcomes), (Access) to treatment, and a lack of understanding about gene therapy (education).

CONCLUSIONS

This Exigency study subgroup sees gene therapy as a positive treatment development that promises an improved quality of life. For this participant group, four issues impact their decision to undergo gene therapy. If the promise of gene therapy is to be realised, these barriers need to be acknowledged and addressed by healthcare professionals, patient organisations, and gene therapy providers.

Expectation and loss when gene therapy for haemophilia is not an option: An exigency sub-study

BACKGROUND

Qualitative studies have explored why people with haemophilia (PwH) might consider or forgo gene therapy, the impact it has had on those who have received it, and what support might be needed throughout the process. No studies have yet examined what withdrawal prior to transfection might mean for PwH and their families.

AIMS

To understand the experiences of PwH and their families of withdrawal from gene therapy and to understand what support mechanisms might be required.

METHODS

Qualitative interviews were conducted with people with severe haemophilia who consented to take part in a gene therapy study in the UK but either withdrew or were withdrawn before transfection.

RESULTS

Nine PwH and a family member were invited to this sub-study. Eight participants were recruited: six PwH (five haemophilia A and one haemophilia B) and two family members. Four participants were excluded from a study after consenting but before transfection, having failed to meet all the inclusion criteria; two withdrew after consenting but before transfection due to concerns including duration of factor expression and the time commitment involved in follow-up. The mean age of participants was 40.5 years (range 25-63 years). Two major themes emerged during the interviews: Expectation and loss.

CONCLUSIONS

PwH have many expectations about the difference gene therapy can make to their lives. Studies show that these expectations may not be fully realised. For those who have either withdrawn or been withdrawn from gene therapy, any expectations they had may now be unachievable. The nature of these expectations and the loss expressed by the participants indicate that support needs to be provided to help them and their families manage it.

Search for Subsolar-Mass Binaries in the First Half of Advanced LIGO's and Advanced Virgo's Third Observing Run

We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2  M_{⊙} and 1.0  M_{⊙} in Advanced LIGO and Advanced Virgo data collected between 1 April 2019 1500 UTC and 1 October 2019 1500 UTC. We extend our previous analyses in two main ways: we include data from the Virgo detector and we allow for more unequal mass systems, with mass ratio q≥0.1. We do not report any gravitational-wave candidates. The most significant trigger has a false alarm rate of 0.14  yr^{-1}. This implies an upper limit on the merger rate of subsolar binaries in the range [220-24200]  Gpc^{-3} yr^{-1}, depending on the chirp mass of the binary. We use this upper limit to derive astrophysical constraints on two phenomenological models that could produce subsolar-mass compact objects. One is an isotropic distribution of equal-mass primordial black holes. Using this model, we find that the fraction of dark matter in primordial black holes in the mass range 0.2  M_{⊙}<m_{PBH}<1.0  M_{⊙} is f_{PBH}≡Ω_{PBH}/Ω_{DM}≲6%. This improves existing constraints on primordial black hole abundance by a factor of ∼3. The other is a dissipative dark matter model, in which fermionic dark matter can collapse and form black holes. The upper limit on the fraction of dark matter black holes depends on the minimum mass of the black holes that can be formed: the most constraining result is obtained at M_{min}=1  M_{⊙}, where f_{DBH}≡Ω_{DBH}/Ω_{DM}≲0.003%. These are the first constraints placed on dissipative dark models by subsolar-mass analyses.

The experiences of people with haemophilia and their families of gene therapy in a clinical trial setting: regaining control, the Exigency study

BACKGROUND

Gene therapy has the potential to change the life experience of people with haemophilia and family members. Few studies have sought to explore the impact of gene therapy on both individuals and families. The aim of this study was to capture real-life experiences of gene therapy in People with haemophilia and their families.

RESULTS

Sixteen participants with severe haemophilia (11 haemophilia A, five haemophilia B), mean age 41.4 years (range 23-75 years), took part in a single qualitative interview; ten were accompanied by a family member. Mean time since transfection was 3.56 years (range 1-10 years). Participants saw their involvement in gene therapy as a positive experience, freeing them from the personal burden of haemophilia and furthering treatment options for the wider haemophilia community. However, participants reported being unprepared for the side effects of immunosuppression. Some also reported feeling unsupported and having little control over what was happening as their factor levels became the focus of the process.

CONCLUSION

The results suggest that strategies need to be put into place to enable PwH fully to understand the process of gene therapy, and thereby make an informed choice as to whether it is a treatment they might wish for themselves. These include early and ongoing education, increased provision of psychosocial support and ongoing qualitative research.

The lived experience of a novel disruptive therapy in a group of men and boys with haemophilia A with inhibitors: Emi & Me

BACKGROUND

People with haemophilia A and inhibitors (PwHi) suffer more orthopaedic complications, bleeding and pain than those without inhibitors. The advent of emicizumab as a prophylactic treatment has led to a reduction in bleed frequency and a significant improvement in overall quality of life. No research to date has examined the nature of this improvement on treated individuals and their families.

AIMS

The Emi & Me study aims to capture the real-life experience of using emicizumab for PwHi and their families.

METHODS

Participants were recruited through treatment centres, social media and by word of mouth. Each participant and a family member, if available, took part in a semistructured qualitative interview. All interviews were recorded, transcribed verbatim and analysed thematically. All elements of the study were reviewed by local statutory authorities and informed consent was sought from all participants.

RESULTS

Fifteen PwHi, mean age 27.2 years (range 8-63 years), most with a family member, participated in a single qualitative interview online (n = 13), by telephone (n = 1) or in person (n = 1). Mean time on emicizumab was 2.26 years (range 1-5 years). Six major themes emerged: bleeds; pain; treatment burden; control; freedom (for both PwHi and family members) and missed potential. Emicizumab prophylaxis has delivered significant improvements in the lives of the participants. Despite these improvements, some participants felt that their pre-existing physical disabilities and the lack of physiotherapy provision had prevented them achieving similar improvements in their functional ability.

CONCLUSION

This study shows that in reducing bleeds, pain and treatment burden, emicizumab had given PwHi greater control over their condition, allowing a sense of freedom they had not experienced with factor VIII or bypassing agent prophylaxis. However, for emicizumab to be truly effective, there is a need to ensure the continued availability and accessibility of robust multidisciplinary support services. Without this, it is unlikely that PwHi will realize the life-changing potential offered either by emicizumab or any other novel treatment approach.

PATIENT OR PUBLIC CONTRIBUTION

A patient participant (who did not wish to be included as an author of the paper) was involved in the design of the study protocol and interview guide.

An exploration of why men with severe haemophilia might not want gene therapy: The exigency study

INTRODUCTION

For many people with haemophilia (PwH) gene therapy offers a potential functional cure. However, some have stated that they do not wish to have gene therapy either now or in the future.

AIM

This sub-study, part of the larger Exigency programme, assesses the attitudes, views and understanding of those who do not wish to undergo gene therapy.

METHODS

Participants were approached via social media and word of mouth referral and invited to participate in a focus group or individual interview to discuss their views. Interviews were recorded, transcribed verbatim and analysed thematically.

RESULTS

Ten adult men with severe haemophilia (eight haemophilia A and two haemophilia B), mean age 34.3 years, participated in a 1-h focus group (n = 9) or interview (n = 1). All were on prophylaxis. None reported significant treatment burden, and all had annual bleeding rates of less than five in the previous 12 months. Four major themes emerged: self-identity and its loss, lack of long-term safety and efficacy data, ongoing concerns about past viral infection, and lack of current treatment burden.

CONCLUSION

There are many concerns about gene therapy, including eligibility, effectiveness and safety, which may result in individuals declining it as a therapy. These concerns may recede as more data are published. This study reveals a psychological dynamic around self-identity and belonging for PwH. The nature of this dynamic is poorly understood and needs exploration to facilitate support for those making decisions about gene therapy.

Parental perspectives on gene therapy for children with haemophilia: The Exigency study

INTRODUCTION

Gene therapy is used in life-limiting conditions of childhood. While not a current therapeutic option for children with haemophilia, it may be considered in the future especially for those where access to treatment is limited.

AIM

To assess the attitudes and opinions of parents of children with haemophilia about gene therapy as a potential future treatment, by understanding their awareness about gene therapy and what they need to know now and in the future; gauging levels of interest in gene therapy for their children; and exploring perceived current motivations and barriers.

METHODS

A mixed methods study with an online questionnaire and in-depth qualitative interviews in focus groups which were analysed using thematic analysis.

RESULTS

One hundred and fifty-eight participants commenced the online survey; 63 were fully completed (39%). 60 had heard of gene therapy but few (17/60 [28.3%]) felt they had a good understanding. 38/60 (63.3%) respondents did not know that gene therapy is not available for children. However, most held positive views: 53/60 (88.3%) saying they would consider it for their child. In the interviews, participants (N = 10, all mothers) discussed their awareness and understanding of gene therapy and opinions about it for children, including how this should be communicated to the child and parents.

CONCLUSION

A coherent, community-wide strategy for communicating information and news about gene therapy should now be provided for children and families living with haemophilia. This should come primarily from trusted haemophilia nursing teams, who can give tailored, age-appropriate, factual advice.

Tumour heterogeneity: a problem in biopsy assessment of the proliferation index of oesophageal adenocarcinomas

Tumour heterogeneity may pose a problem when biopsy specimens are taken to measure proliferation (for example, in assessing response to therapy). Two "biopsy specimens" were taken from the centre and two from the edge of the luminal surface of 20 resected oesophageal adenocarcinomas. The proliferation index for each "biopsy specimen" was measured by counting Ki67 labelled nuclei in histological sections. The proliferation index was not associated with tumour differentiation or stage. There was site specific heterogeneity with a significant difference in proliferation index between the central (mean (SD) 36.4 (9.7)) and edge "biopsy specimens" (39.3 (9.9)). There was, however, a wide range of differences between pairs of "biopsy specimens" from both sites. In conclusion, if a tumour is to be sampled for measurement of the proliferation index before and after treatment, then the sequential biopsy specimens (preferably duplicated on each occasion) should be taken consistently from a leading edge of the lesion.

Subcutaneous panniculitis-like T-cell lymphoma: a clinicopathological, immunophenotypic and molecular analysis of six patients

BACKGROUND

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare cytotoxic T-cell lymphoma of the skin. In the World Health Organization classification of T-cell and natural killer cell lymphoma it is listed as an example of extranodal lymphoma. In practice, however, it is most likely to present to a dermatologist.

OBJECTIVES

To describe the clinicopathological, immunophenotypic and molecular features of six U.K. patients with SPTCL.

METHODS

The clinical, histological and immunophenotypic features were reviewed. T-cell receptor (TCR) gene analysis was performed on blood and tissue samples using polymerase chain reaction/single-strand conformational polymorphism analysis of the TCR-gamma gene using consensus primers. In situ hybridization was performed on lesional skin to detect mRNA for Epstein-Barr virus (EBV).

RESULTS

All patients presented with subcutaneous nodules, plaques or ulceration, and three had systemic symptoms. All biopsies exhibited an infiltrate of medium to large pleomorphic cells involving the subcutis with characteristic rimming of fat spaces. Five showed areas of necrosis, but only one showed marked cytophagia. In three cases the neoplastic cells did not express TCR-beta. One was strongly p53 positive, and the other two were CD56 positive. Both these patients showed epidermal involvement with lichenoid changes histologically, and both developed the haemophagocytic syndrome. The other three cases were TCR-beta positive, CD8 positive and CD56 negative. All cases were positive with pan T-cell markers and also for the cytotoxic granule protein T-cell intracellular antigen-1 and granzyme B. All cases were EBV negative both by immunostaining (latent membrane protein-1) and by in situ hybridization (EBV-encoded mRNA). TCR gene analysis revealed a T-cell clone in four of five cases; two of these patients had an identical T-cell clone in the peripheral blood. The median survival was 16 months. However, two of the three TCR-beta-negative patients have died, whereas none of the TCR-beta-positive patients has died.

CONCLUSIONS

This is the first series of SPTCL patients to be reported in the U.K. and the data support the view that there are two subsets of SPTCL: those derived from gammadelta T cells which carry a poor prognosis, and are usually CD56 positive, and a more indolent group derived from alphabeta T cells.

Expression of E-cadherin in oesophageal carcinomas from the UK and China: disparities in prognostic significance

AIMS

To study the expression and prognostic significance of the cell adhesion molecule E-cadherin in oesophageal tumours from the UK (low risk area) and China (high risk area).

METHODS

E-cadherin expression was measured immunohistochemically in resected tumours from 17 patients in the UK with adenocarcinoma, 23 patients from the UK with squamous carcinoma, and 30 patients from China with squamous carcinomas who survived for five years postoperatively and compared with similar tumours from patients in the same regions who did not survive (140 tumours in all).

RESULTS

Normal squamous epithelial cells and well differentiated areas of tumours showed membranous staining for E-cadherin expression. Cytoplasmic staining, heterogeneous staining, or an absence of staining was seen in dysplastic epithelium and in less well differentiated areas of tumours. Only one of 140 primary tumours had homogeneous membranous expression. In tumours from UK patients with adenocarcinoma (p = 1.00) and from Chinese patients with squamous carcinomas (p = 0.06) there was no correlation between E-cadherin absence and non-survival. In tumours from UK patients with squamous carcinomas there was a significant correlation between absence of E-cadherin and non-survival (p = 0.009). Tumours from UK patients with squamous carcinoma who survived were significantly less likely to be E-cadherin absent than those from Chinese patients with squamous carcinomas who survived (p = 0.007). Multivariate analysis (n = 37 UK, paired data) showed that absence of E-cadherin in the primary tumour was a weak independent prognostic factor for non-survival (30% significance level; p = 0.26; odds ratio = 3.56). In UK nodal metastases there was no correlation between E-cadherin expression and survival.

CONCLUSIONS

Squamous carcinomas from UK patients differed from both adenocarcinomas from UK patients and carcinomas from Chinese patients with respect to E-cadherin expression and prognostic significance. In tumours from UK patients, E-cadherin absence in the primary carcinoma (a weak independent prognostic factor) but not metastases correlated with non-survival.

Lack of correlation of P-glycoprotein expression with response to MIC chemotherapy in oesophageal cancer

The multidrug resistance gene product P-glycoprotein (P-GP) was assessed immunohistochemically (by antibody JSB-1) in biopsy specimens from 27 oesophageal squamous carcinomas and 10 adenocarcinomas before treatment with mitomycin, ifosfamide and cisplatin (MIC). Tumours were assessed following treatment and correlation with response sought. Of the squamous carcinomas, 74% (20/27) responded to MIC but only one expressed P-GP before and after treatment. Of the adenocarcinomas, 30% (three of 10) responded. Seven of the 10 adenocarcinomas expressed P-GP before treatment but all 10 were P-GP positive after chemotherapy. The difference in prevalence and induction of P-GP between the histological types was highly significant and may correlate with the greater response to MIC seen in squamous carcinomas compared with adenocarcinomas. P-GP cannot be used as a predictive marker of response as tumours express it inconsistently with response to MIC. Resistance to MIC may be due to other mechanisms.

Expression of p53 protein in oesophageal carcinoma: clinicopathological correlation and prognostic significance

Correlation of p53 expression with 5-year survival and histopathological parameters was examined immunohistochemically in two groups of 30 patients with oesophageal carcinoma (5-year survivors versus non-survivors). Tumour type, sex, operative procedure and age were matched. Some 64 per cent of squamous carcinomas and 79 per cent of adenocarcinomas were p53 positive. Normal squamous, normal glandular and metaplastic glandular epithelia were negative. Dysplastic squamous and glandular epithelium adjacent to tumours was positive when the tumour was positive and negative when it was not. Univariate analysis showed that nodal status (P = 0.001), and grade and depth of invasion (both P = 0.01) correlated with outcome. Correlation of tumour grade with outcome, when the most poorly differentiated area is used, is a novel finding for oesophageal carcinoma. The p53 status was not significantly associated with survival or any of these parameters.

Fatty acid synthesis: a potential selective target for antineoplastic therapy

OA-519 is a prognostic molecule found in tumor cells from breast cancer patients with markedly worsened prognosis. We purified OA-519 from human breast carcinoma cells, obtained its peptide sequence, and unambiguously identified it as fatty acid synthase through sequence homology and enzymology. Tumor fatty acid synthase is an approximately 270-kDa polypeptide which specifically abolished immunostaining of human breast cancers by anti-OA-519 antibodies. Tumor fatty acid synthase oxidized NADPH in a malonyl-CoA-dependent fashion and synthesized fatty acids composed of 80% palmitate, 10% myristate, and 10% stearate from acetyl-CoA, malonyl-CoA, and NADPH with a specific activity of 624 nmol of NADPH oxidized per min per mg. Tumor cell lines with elevated fatty acid synthase showed commensurate increases in incorporation of [U-14C]acetate into acylglycerols demonstrating that fatty acid synthase increases occur in the context of overall increases in endogenous fatty acid synthesis. Cerulenin inhibited acylglycerol synthesis in tumor cells and fibroblast controls in a dose-dependent fashion and also caused a growth inhibition which generally paralleled the level of endogenous fatty acid synthesis. Supraphysiologic levels of palmitate, 14 microM in dimethyl sulfoxide, significantly reversed the growth inhibition caused by cerulenin at concentrations of up to 5 micrograms/ml, indicating that cerulenin-mediated growth inhibition was due to fatty acid synthase inhibition.

[The preparation of food and environmental samples for residue analysis of pesticides and PCBs by continuous steam distillation]

The treatment of water, soil and food samples was tested with a modified equipment of glass for simultaneous steam distillation/solvent extraction. Spiked samples with 22 pesticides (most of them contained halogen) and PCB yielded good or very good recoveries after 1.5 h for water samples and after 5 h for soil and plant food samples, respectively. This method is ecologically beneficial, and because it needs only a small amount of solvent (less than 10 ml) it is not expensive and may be used as a quick screening in several fields.

Characterization of genetic markers in the 3' end of the apo B gene and their use in family and population studies

The 3' end of the apo B gene is highly polymorphic. Two point mutations in the coding sequence of the gene create EcoRI (E+, E-) and XbaI (X+, X-) RFLPs. The two loci are in random association and the frequency of the four haplotypes, E+X+, E+X-, E-X+ and E-X- in the normolipidaemic population are 0.68, 0.30, 0.02 and 0.00, respectively. Although the polymorphic nucleotide underlying the EcoRI RFLP creates an amino acid substitution in the apo B protein (Glu----Lys) in a region close to a putative LDL-receptor recognition site(s), we find no statistically significant difference in the frequency of the apo BGlu and apo BLys alleles in hyperlipidaemic patients (familial hypercholesterolaemia, type IIA with no tendon xanthomas, IIB and probably IV) and the normolipidaemic population. In contrast, we confirm previous findings, that the X+ allele is in linkage disequilibrium with a genetic locus that predisposes to the development of higher fasting plasma triglyceride levels than the X- allele. We have characterized a highly polymorphic region immediately 3' to the apo B gene. At least 5 alleles of this locus exist in the population and our family studies show it should be an extremely informative locus to use in studies where polymorphic or mutant apo B alleles are suspected to underly certain forms of familial hyperlipidaemia. DNA sequence analysis of this highly polymorphic locus shows that the variation is entirely attributable to the number of times the simple repeating sequence 5'-TTTATAATTAAAATATTTATAATTAAATAT-3' is present.