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Featured researches published by Peter R. E. Johnson.


Blood | 2008

Five new pedigrees with inherited RUNX1 mutations causing familial platelet disorder with propensity to myeloid malignancy

Carolyn Owen; Cynthia L. Toze; Anna Koochin; Donna L. Forrest; Clayton A. Smith; Jane Stevens; Shannon C. Jackson; Man-Chiu Poon; Gary Sinclair; Brian Leber; Peter R. E. Johnson; Anthony Macheta; John A. Liu Yin; Michael J. Barnett; T. Andrew Lister; Jude Fitzgibbon

Familial platelet disorder with propensity to myeloid malignancy (FPD/AML) is an autosomal dominant syndrome characterized by platelet abnormalities and a predisposition to myelodysplasia (MDS) and/or acute myeloid leukemia (AML). The disorder, caused by inherited mutations in RUNX1, is uncommon with only 14 pedigrees reported. We screened 10 families with a history of more than one first degree relative with MDS/AML for inherited mutations in RUNX1. Germ- line RUNX1 mutations were identified in 5 pedigrees with a 3:2 predominance of N-terminal mutations. Several affected members had normal platelet counts or platelet function, features not previously reported in FPD/AML. The median incidence of MDS/AML among carriers of RUNX1 mutation was 35%. Individual treatments varied but included hematopoietic stem cell transplantation from siblings before recognition of the inherited leukemogenic mutation. Transplantation was associated with a high incidence of complications including early relapse, failure of engraftment, and posttransplantation lymphoproliferative disorder. Given the small size of modern families and the clinical heterogeneity of this syndrome, the diagnosis of FPD/AML could be easily overlooked and may be more prevalent than previously recognized. Therefore, it would appear prudent to screen young patients with MDS/AML for RUNX1 mutation, before consideration of sibling hematopoietic stem cell transplantation.


Haematologica | 2012

Cyclophosphamide, thalidomide, and dexamethasone as induction therapy for newly diagnosed multiple myeloma patients destined for autologous stem-cell transplantation: MRC Myeloma IX randomized trial results

Gareth J. Morgan; Faith E. Davies; Walter Gregory; Sue E. Bell; Alexander J. Szubert; Nuria Navarro Coy; Gordon Cook; Sylvia Feyler; Peter R. E. Johnson; Claudius Rudin; Mark T. Drayson; Roger Owen; Fiona M. Ross; Nigel H. Russell; Graham Jackson; J. Anthony Child

Background Thalidomide is active in multiple myeloma and is associated with minimal myelosuppression, making it a good candidate for induction therapy prior to high-dose therapy with autologous stem-cell transplantation. Design and Methods Oral cyclophosphamide, thalidomide, and dexamethasone was compared with infusional cyclophosphamide, vincristine, doxorubicin, and dexamethasone in patients with newly diagnosed multiple myeloma. Results The post-induction overall response rate (≥ partial response) for the intent-to-treat population was significantly higher with cyclophosphamide-thalidomide-dexamethasone (n=555) versus cyclophosphamide-vincristine-doxorubicin-dexamethasone (n=556); 82.5% versus 71.2%; odds ratio 1.91; 95% confidence interval 1.44–2.55; P<0.0001. The complete response rates were 13.0% with cyclophosphamide-thalidomide-dexamethasone and 8.1% with cyclophos-phamide-vincristine-doxorubicin-dexamethasone (P=0.0083), with this differential response being maintained in patients who received autologous stem-cell transplantation (post-transplant complete response 50.0% versus 37.2%, respectively; P=0.00052). Cyclophosphamide-thalidomide-dexamethasone was non-inferior to cyclophosphamide-vincristine-doxorubicin-dexamethasone for progression-free and overall survival, and there was a trend toward a late survival benefit with cyclophosphamide-thalidomide-dexamethasone in responders. A trend toward an overall survival advantage for cyclophosphamide-thalidomide-dexamethasone over cyclophosphamide-vincristine-doxorubicin-dexamethasone was also observed in a subgroup of patients with favorable interphase fluorescence in situ hybridization. Compared with cyclophosphamide-vincristine-doxorubicin-dexamethasone, cyclophosphamide-thalidomide-dexamethasone was associated with more constipation and somnolence, but a lower incidence of cytopenias. Conclusions The cyclophosphamide-thalidomide-dexamethasone regimen showed improved response rates and was not inferior in terms of survival outcomes to the standard infusional regimen of cyclophosphamide-vincristine-doxorubicin-dexamethasone. Based on its oral administration and the reduced incidence of infection and cytopenia, cyclophosphamide-thalidomide-dexa-methasone may be considered an effective induction therapy option for patients with newly diagnosed multiple myeloma. (ISRCTN: 68454111)


Bone Marrow Transplantation | 2005

A prospective study of real-time panfungal PCR for the early diagnosis of invasive fungal infection in haemato-oncology patients

Niove E. Jordanides; Elaine K. Allan; Lorna A. McLintock; Mhairi Copland; M. Devaney; Karen Stewart; Anne Parker; Peter R. E. Johnson; Tessa L. Holyoake; Brian Jones

Summary:A blinded prospective study was performed to determine whether screening of whole blood using a real-time, panfungal polymerase chain reaction (PCR) technique could predict the development of invasive fungal infection (IFI) in immunocompromised haemato-oncology patients. In all, 78 patients (125 treatment episodes) were screened twice weekly by real-time panfungal PCR using LightCycler™ technology. IFI was documented in 19 treatment episodes (five proven, three probable and 11 possible), and in 12, PCR was sequentially positive. PCR positivity occurred in: 4/5 proven; 2/3 probable; 6/11 possible; and 29/106 with no IFI. In 8/12 with IFI and sequentially positive PCR results, PCR positivity occurred before (median 19.5 days) and in 4/12 (median 10.5 days) after the initiation of empirical antifungal therapy. Based on sequential positive results for proven/probable IFI sensitivity, specificity, positive predictive value and negative predictive value were 75, 70, 15 and 98%, respectively. Real-time panfungal PCR is a sensitive tool for the early diagnosis of IFI in immunocompromised haemato-oncology patients. It may be most useful as a screening method in high-risk patients, either to direct early pre-emptive antifungal therapy or to determine when empirical antifungal therapy can be withheld in patients with antibiotic--resistant neutropenic fever. However, these strategies require further assessment in comparative clinical trials.


Blood | 2010

Impact of in vivo alemtuzumab dose before reduced intensity conditioning and HLA-identical sibling stem cell transplantation: pharmacokinetics, GVHD, and immune reconstitution

Ronjon Chakraverty; Guillermo Orti; Michael Roughton; Jun Shen; Adele Fielding; Panagiotis D. Kottaridis; Donald Milligan; Matthew Collin; Charles Crawley; Peter R. E. Johnson; Andrew Clark; Anne Parker; Adrian Bloor; Ruth Pettengell; John A. Snowden; Andrew R. Pettitt; Richard E. Clark; Geoff Hale; Karl S. Peggs; Kirsty Thomson; Emma Morris; Stephen Mackinnon

In vivo alemtuzumab reduces the risk of graft-versus-host disease (GVHD) and nonrelapse mortality after reduced intensity allogeneic transplantation. However, it also delays immune reconstitution, leading to frequent infections and potential loss of graft-versus-tumor responses. Here, we tested the feasibility of alemtuzumab dose deescalation in the context of fludarabine-melphalan conditioning and human leukocyte antigen (HLA)-identical sibling transplantation. Alemtuzumab was given 1-2 days before graft infusion, and dose reduced from 60 mg to 20 mg in 4 sequential cohorts (total n = 106). Pharmacokinetic studies were fitted to a linear, 2-compartment model in which dose reduction led to incomplete saturation of CD52 binding sites and greater antibody clearance. Increased elimination was particularly evident in the 20-mg group in patients who had CD52-expressing tumors at time of transplantation. The 20-mg dose was also associated with greater risk of severe GVHD (acute grade III-IV or chronic extensive) compared with > 20 mg (hazard ratio, 6.7; 95% CI, 2.5-18.3). In contrast, dose reduction to 30 mg on day -1 was associated with equivalent clinical outcomes to higher doses but better lymphocyte recovery at 12 months. In conclusion, alemtuzumab dose reduction to 30 mg is safe in the context of reduced intensity conditioning and HLA-identical sibling transplantation. This trial was registered at http://www.ncrn.org.uk as UKCRN study 1415.


British Journal of Haematology | 2006

Phase I/II study of vaccination with dendritic-like leukaemia cells for the immunotherapy of acute myeloid leukaemia.

Huw Roddie; M. Klammer; C. Thomas; R. Thomson; A. Atkinson; Anne Sproul; M. Waterfall; Kay Samuel; John A. Liu Yin; Peter R. E. Johnson; Marc Turner

Twenty‐two patients with acute myeloid leukaemia were recruited into a phase I/II clinical trial investigating the vaccination of patients in complete remission (CR) with autologous dendritic‐like leukaemia cells (DLLC). At trial entry, leukaemia cells were harvested and tested for their ability to undergo cytokine‐induced dendritic cell differentiation. Patients were then treated with intensive chemotherapy. Five patients achieved both CR and had leukaemia cells that successfully underwent differentiation and therefore proceeded to vaccination. Four escalating doses of DLLC were administered weekly by subcutaneous injection. Vaccination was generally well tolerated although one patient developed extensive eczema and an increased antinuclear factor titre possibly indicating induction of autoimmunity. Development of anti‐leukaemic T‐cell responses was assessed by enzyme‐linked immunospot analysis of gamma‐interferon secreting T lymphocytes and by human leucocyte antigen tetramer analysis for WT1‐specific T cells. Increases in anti‐leukaemic T‐cell responses were demonstrated in four patients, but only two of the five remained in remission more than 12 months postvaccination. The study has demonstrated that generation of DLLC is feasible in only a subgroup of patients and is currently neither broadly applicable or clinically effective.


JAMA | 2015

Autologous Hematopoetic Stem Cell Transplantation for Refractory Crohn Disease: A Randomized Clinical Trial.

Christopher J. Hawkey; Matthieu Allez; Miranda M. Clark; Myriam Labopin; James O. Lindsay; Elena Ricart; Gerhard Rogler; Montserrat Rovira; Jack Satsangi; Silvio Danese; Nigel H. Russell; John G. Gribben; Peter R. E. Johnson; Jérôme Larghero; Catherine Thieblemont; Daan Dierickx; Adalberto Ibatici; Timothy Littlewood; Francesco Onida; Urs Schanz; Severine Vermeire; Jean-Frederic Colombel; Jean Paul Jouet; Elizabeth T. Clark; Riccardo Saccardi; Alan Tyndall; Simon Travis; Dominique Farge

IMPORTANCE Case reports and series suggest hematopoietic stem cell transplantation (HSCT) may benefit some patients with Crohn disease. OBJECTIVE To evaluate the effect of autologous HSCT on refractory Crohn disease. DESIGN, SETTING, AND PARTICIPANTS Parallel-group randomized clinical trial conducted in 11 European transplant units from July 2007 to September 2011, with follow-up through March 2013. Patients were aged 18 to 50 years with impaired quality of life from refractory Crohn disease not amenable to surgery despite treatment with 3 or more immunosuppressive or biologic agents and corticosteroids. INTERVENTIONS All patients underwent stem cell mobilization before 1:1 randomization to immunoablation and HSCT (n = 23) or control treatment (HSCT deferred for 1 year [n = 22]). All were given standard Crohn disease treatment as needed. MAIN OUTCOMES AND MEASURES Sustained disease remission at 1 year, a composite primary end point comprising clinical remission (Crohn Disease Activity Index (CDAI) <150 [range, 0-600]), no use of corticosteroids or immunosuppressive or biologic drugs for at least the last 3 months, and no endoscopic or radiological evidence of active (erosive) disease anywhere in the gastrointestinal (GI) tract. Secondary outcomes were individual components of the primary composite outcome and other measures of disease activity, laboratory results, quality of life and functional status, and GI tract imaging. RESULTS Twenty-three patients underwent HSCT and 22 received standard Crohn disease treatment (controls). Sustained disease remission was achieved in 2 patients undergoing HSCT (8.7%) vs 1 control patient (4.5%) (absolute difference, 4.2% [95% CI, -14.2% to 22.6%]; P = .60). Fourteen patients undergoing HSCT (61%) vs 5 control patients (23%) had discontinued immunosuppressive or biologic agents or corticosteroids for at least 3 months (difference, 38.1% [95% CI, 9.3% to 59.3%]; P = .01). Ten vs 2 patients had a CDAI less than 150 (remission) at the final evaluation, 8 (34.8%) vs 2 (9.1%) for 3 or more months (difference, 25.7% [95% CI, 1.1% to 47.1%]; P = .052). Eight (34.8%) vs 2 (9.1%) patients were adjudicated free of active disease on endoscopy and radiology at final assessment (difference, 25.7% [95% CI, 1.1% to 47.1%]; P = .054). There were 76 serious adverse events in patients undergoing HSCT vs 38 in controls. One patient undergoing HSCT died. CONCLUSIONS AND RELEVANCE Among adult patients with refractory Crohn disease not amenable to surgery who had impaired quality of life, HSCT, compared with conventional therapy, did not result in a statistically significant improvement in sustained disease remission at 1 year and was associated with significant toxicity. These findings do not support the widespread use of HSCT for patients with refractory Crohn disease. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00297193.


British Journal of Haematology | 2006

The clinical outcome and toxicity of high-dose chemotherapy and autologous stem cell transplantation in patients with myeloma or amyloid and severe renal impairment: a British Society of Blood and Marrow Transplantation study.

Jennifer M. Bird; Rhian Fuge; Bhawna Sirohi; Jane F. Apperley; Ann Hunter; John A. Snowden; Premini Mahendra; Donald Milligan; Jenny L. Byrne; Timothy Littlewood; Chris Fegan; Grant McQuaker; Antonio Pagliuca; Peter R. E. Johnson; Amin Rahemtulla; Curly Morris; David I. Marks

The outcome of high‐dose chemotherapy (HDT) was evaluated retrospectively in 27 patients with myeloma and four patients with AL amyloidosis with severe renal impairment. Twenty‐three patients were receiving dialysis and the rest had a creatinine clearance of <20 ml/min. The median melphalan dose was 140 mg/m2 (range: 60–200 mg/m2), but 10 patients (37%) received 200 mg/m2. Myeloid and platelet engraftment were similar to that seen in patients without renal failure. Five of 27 patients died of transplant‐related toxicity before the day 100. Twenty of 27 patients had a response (70%). The median time to disease progression was 32 months (range: 6–54 months) and the median time to best response was 6·5 months. Four of 17 evaluable patients (24%) became dialysis‐independent at a median of 5 months post‐HDT/stem cell transplantation. At a median follow‐up of 70 months, 7/23 patients with myeloma were alive but three of these seven patients had progressive disease. Two of the four patients with amyloidosis have survived. HDT is feasible in these patients and results in 5‐year survival in about one‐third of patients.


British Journal of Haematology | 2002

Spontaneous clinical regression in chronic lymphocytic leukaemia

Ranjit Thomas; Isabel Ribeiro; Patricia Shepherd; Peter R. E. Johnson; Margaret Cook; Anil Lakhani; Richard Kaczmarski; Patrick Carrington; Daniel Catovsky

Summary. Chronic lymphocytic leukaemia (CLL) is a B‐cell disorder, which has a median survival of over 10 years from diagnosis for stage A disease. The natural history of stage A disease is generally indolent or only slowly progressive. It is less well known that CLL may undergo spontaneous regression. We report a series of 10 such cases (eight stage A and two stage B) followed at our institutions.


Blood | 2013

Autologous stem cell transplantation for enteropathy-associated T-cell lymphoma: a retrospective study by the EBMT

Esa Jantunen; Ariane Boumendil; Herve Finel; Jian-Jian Luan; Peter R. E. Johnson; Alessandro Rambaldi; Andrew P. Haynes; Michel A. Duchosal; Wolfgang Bethge; Pierre Biron; Kristina Carlson; Charles Craddock; Claudius Rudin; Jürgen Finke; Gilles Salles; Frank Kroschinsky; Anna Sureda; Peter Dreger

Enteropathy-associated T-cell lymphoma (EATL) is a rare subtype of peripheral T-cell lymphomas with a poor prognosis. Autologous stem cell transplantation (ASCT) was retrospectively evaluated as a consolidation or salvage strategy for EATL. The analysis included 44 patients who received ASCT for EATL between 2000 and 2010. Thirty-one patients (70%) were in first complete or partial remission at the time of the ASCT. With a median follow-up of 46 months, relapse incidence, progression-free survival, and overall survival were 39%, 54%, and 59% at 4 years, respectively, with only one relapse occurring beyond 18 months posttransplant. There was a trend for better survival in patients transplanted in first complete or partial remission at 4 years (66% vs 36%; P = .062). ASCT is feasible in selected patients with EATL and can yield durable disease control in a significant proportion of the patients.


British Journal of Haematology | 2005

Poor performance of galactomannan and mannan sandwich enzyme-linked immunosorbent assays in the diagnosis of invasive fungal infection

Elaine K. Allan; Niove E. Jordanides; Lorna A. McLintock; Mhairi Copland; Maureen Devaney; Karen Stewart; Anne Parker; Peter R. E. Johnson; Tessa L. Holyoake; Brian Jones

The Platelia Aspergillus and Platelia Candida (BioRad Laboratories Ltd, Hertfordshire, UK) are commercially available sandwich enzyme-linked immunosorbent assay (ELISA) kits for the detection of galactomannan (GM) and mannan (M) respectively. A number of prospective studies report excellent sensitivities (90–95%) and specificities using the Platelia Aspergillus for the diagnosis of invasive aspergillosis (IA) (McLintock & Jones, 2004). The European Organisation for the Research and Treatment of Cancer and the Mycosis Study Group (EORTC/ MSG) definitions of invasive fungal infection (IFI) include positive GM antigen testing as a microbiological criterion (Ascioglu et al, 2002). Other studies demonstrate poorer sensitivities (0–50%) (McLintock & Jones, 2004) and controversy exits over the most appropriate positive cut-off (Maertens et al, 2004). There are no prospective studies which evaluate the Platelia Candida and retrospective studies report modest sensitivities (30–69%) (McLintock & Jones, 2004). Positive M antigen testing is not included in EORTC/MSG definitions of IFI. A prospective blinded study was performed to assess the value of twice-weekly screening of serum specimens, from haemato-oncology patients at highand intermediate high-risk of IFI (Prentice et al, 2000), with Platelia Aspergillus and Platelia Candida ELISAs. Between December 2000 and December 2001, adult patients receiving allogeneic or autologous stem cell transplantation (SCT) or intensive chemotherapy were recruited. A treatment episode was defined as a single course of chemotherapy, an autologous SCT or an allogeneic SCT until day 100 following the transplant, or a course of corticosteroid therapy for graft-versus-host disease. An investigator blinded to the patient data performed the ELISAs according to the manufacturer’s instructions. Each sample was run in duplicate. Samples were re-tested if the coefficient of variation between duplicates was more than 20%. IFI was classified as proven, probable or possible according to the EORTC/MSG definitions (Ascioglu et al, 2002). As the Platelia Aspergillus ELISA was being evaluated it was excluded from the EORTC/MSG definitions. The Platelia Candida ELISA assay was discontinued after analysis of 82 episodes as 61% of the kits failed the manufacturer’s validation criteria and results were therefore uninterpretable. Additionally, approximately 30% of the available ELISA results were non-reproducible. A total of 1625 Platelia Aspergillus ELISA results, from 125 treatment episodes, involving 78 patients, aged 16–76 years (mean 42, median 44Æ5 years), were analysed. IFI was documented in 19/125 (15Æ2%) treatment episodes: five proven (all candida); three probable (two Candida, one mixed infection with Candida and Aspergillus); and 11 possible (all Aspergillus). The Platelia Aspergillus ELISA results were analysed at three different positive cut-offs: >1Æ5 (manufacturer’s recommended positive cut-off); >1Æ0; and >0Æ5 (Table I). Using a positive cut-off of >1Æ5, sequential positive (‡ 2 consecutive) results were recorded in only one of 125 treatment episodes, during which the patient had proven invasive candidiasis (IC) but no EORTC/MSG evidence of IA. In the 12 cases of EORTC/MSG-defined IA (one probable and

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Dive into the Peter R. E. Johnson's collaboration.

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John A. Liu Yin

Manchester Royal Infirmary

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Anne Parker

Beatson West of Scotland Cancer Centre

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Anna Sureda

University of Cambridge

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Charles Craddock

Queen Elizabeth Hospital Birmingham

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Christopher P. Fox

Nottingham University Hospitals NHS Trust

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Claudius Rudin

Royal Devon and Exeter Hospital

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John A. Snowden

Royal Hallamshire Hospital

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