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Dive into the research topics where Mahesh K.B. Parmar is active.

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Featured researches published by Mahesh K.B. Parmar.


Lancet Oncology | 2016

Addition of docetaxel or bisphosphonates to standard of care in men with localised or metastatic, hormone-sensitive prostate cancer: a systematic review and meta-analyses of aggregate data

Claire Vale; Sarah Burdett; Larysa Rydzewska; Laurence Albiges; Nw Clarke; David E. Fisher; Karim Fizazi; Gwenaelle Gravis; Nicholas D. James; Malcolm David Mason; Mahesh K.B. Parmar; Christopher Sweeney; Matthew R. Sydes; Bertrand Tombal; Jayne Tierney

Summary Background Results from large randomised controlled trials combining docetaxel or bisphosphonates with standard of care in hormone-sensitive prostate cancer have emerged. In order to investigate the effects of these therapies and to respond to emerging evidence, we aimed to systematically review all relevant trials using a framework for adaptive meta-analysis. Methods For this systematic review and meta-analysis, we searched MEDLINE, Embase, LILACS, and the Cochrane Central Register of Controlled Trials, trial registers, conference proceedings, review articles, and reference lists of trial publications for all relevant randomised controlled trials (published, unpublished, and ongoing) comparing either standard of care with or without docetaxel or standard of care with or without bisphosphonates for men with high-risk localised or metastatic hormone-sensitive prostate cancer. For each trial, we extracted hazard ratios (HRs) of the effects of docetaxel or bisphosphonates on survival (time from randomisation until death from any cause) and failure-free survival (time from randomisation to biochemical or clinical failure or death from any cause) from published trial reports or presentations or obtained them directly from trial investigators. HRs were combined using the fixed-effect model (Mantel-Haenzsel). Findings We identified five eligible randomised controlled trials of docetaxel in men with metastatic (M1) disease. Results from three (CHAARTED, GETUG-15, STAMPEDE) of these trials (2992 [93%] of 3206 men randomised) showed that the addition of docetaxel to standard of care improved survival. The HR of 0·77 (95% CI 0·68–0·87; p<0·0001) translates to an absolute improvement in 4-year survival of 9% (95% CI 5–14). Docetaxel in addition to standard of care also improved failure-free survival, with the HR of 0·64 (0·58–0·70; p<0·0001) translating into a reduction in absolute 4-year failure rates of 16% (95% CI 12–19). We identified 11 trials of docetaxel for men with locally advanced disease (M0). Survival results from three (GETUG-12, RTOG 0521, STAMPEDE) of these trials (2121 [53%] of 3978 men) showed no evidence of a benefit from the addition of docetaxel (HR 0·87 [95% CI 0·69–1·09]; p=0·218), whereas failure-free survival data from four (GETUG-12, RTOG 0521, STAMPEDE, TAX 3501) of these trials (2348 [59%] of 3978 men) showed that docetaxel improved failure-free survival (0·70 [0·61–0·81]; p<0·0001), which translates into a reduced absolute 4-year failure rate of 8% (5–10). We identified seven eligible randomised controlled trials of bisphosphonates for men with M1 disease. Survival results from three of these trials (2740 [88%] of 3109 men) showed that addition of bisphosphonates improved survival (0·88 [0·79–0·98]; p=0·025), which translates to 5% (1–8) absolute improvement, but this result was influenced by the positive result of one trial of sodium clodronate, and we found no evidence of a benefit from the addition of zoledronic acid (0·94 [0·83–1·07]; p=0·323), which translates to an absolute improvement in survival of 2% (−3 to 7). Of 17 trials of bisphosphonates for men with M0 disease, survival results from four trials (4079 [66%] of 6220 men) showed no evidence of benefit from the addition of bisphosphonates (1·03 [0·89–1·18]; p=0·724) or zoledronic acid (0·98 [0·82–1·16]; p=0·782). Failure-free survival definitions were too inconsistent for formal meta-analyses for the bisphosphonate trials. Interpretation The addition of docetaxel to standard of care should be considered standard care for men with M1 hormone-sensitive prostate cancer who are starting treatment for the first time. More evidence on the effects of docetaxel on survival is needed in the M0 disease setting. No evidence exists to suggest that zoledronic acid improves survival in men with M1 or M0 disease, and any potential benefit is probably small. Funding Medical Research Council UK.


International Journal of Technology Assessment in Health Care | 1996

Bias in the analysis and reporting of randomized controlled trials.

Lesley Stewart; Mahesh K.B. Parmar

The most reliable information on any type of medical intervention is provided by the results of randomized clinical trials (RCTs). In response to increasing pressure to make effective use of limited resources, increasing numbers of health professionals rely on the medical literature, in particular reports of RCTs. However, RCTs may be influenced by a number of factors that introduce bias during the conduct, analysis, and reporting of the trial. Trials may be described as random, when in fact only quasi-random means of treatment allocation have been used; patients may be selectively removed from the analysis; and the report may restrict presentation to or give undue emphasis to only the analyses that yield positive results. The implications of such bias are discussed with particular reference to the effect that they may have on reviews and meta-analyses.


Lancet Oncology | 2017

Role of radiotherapy fractionation in head and neck cancers (MARCH): an updated meta-analysis

B. Lacas; Jean Bourhis; Jens Overgaard; Qiang Zhang; Vincent Grégoire; Matthew Nankivell; Björn Zackrisson; Zbigniew Szutkowski; Rafał Suwiński; Michael Poulsen; Brian O'Sullivan; Renzo Corvò; Sarbani Ghosh Laskar; Carlo Fallai; Hideya Yamazaki; Werner Dobrowsky; Kwan Ho Cho; Beth M. Beadle; Johannes A. Langendijk; Celia Maria Pais Viegas; John Hay; Mohamed Lotayef; Mahesh K. B. Parmar; Anne Aupérin; Carla M.L. van Herpen; P. Maingon; Andy Trotti; Cai Grau; Jean-Pierre Pignon; Pierre Blanchard

BACKGROUNDnThe Meta-Analysis of Radiotherapy in squamous cell Carcinomas of Head and neck (MARCH) showed that altered fractionation radiotherapy is associated with improved overall and progression-free survival compared with conventional radiotherapy, with hyperfractionated radiotherapy showing the greatest benefit. This update aims to confirm and explain the superiority of hyperfractionated radiotherapy over other altered fractionation radiotherapy regimens and to assess the benefit of altered fractionation within the context of concomitant chemotherapy with the inclusion of new trials.nnnMETHODSnFor this updated meta-analysis, we searched bibliography databases, trials registries, and meeting proceedings for published or unpublished randomised trials done between Jan 1, 2009, and July 15, 2015, comparing primary or postoperative conventional fractionation radiotherapy versus altered fractionation radiotherapy (comparison 1) or conventional fractionation radiotherapy plus concomitant chemotherapy versus altered fractionation radiotherapy alone (comparison 2). Eligible trials had to start randomisation on or after Jan 1, 1970, and completed accrual before Dec 31, 2010; had to have been randomised in a way that precluded prior knowledge of treatment assignment; and had to include patients with non-metastatic squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx undergoing first-line curative treatment. Trials including a non-conventional radiotherapy control group, investigating hypofractionated radiotherapy, or including mostly nasopharyngeal carcinomas were excluded. Trials were grouped in three types of altered fractionation: hyperfractionated, moderately accelerated, and very accelerated. Individual patient data were collected and combined with a fixed-effects model based on the intention-to-treat principle. The primary endpoint was overall survival.nnnFINDINGSnComparison 1 (conventional fractionation radiotherapy vs altered fractionation radiotherapy) included 33 trials and 11u2008423 patients. Altered fractionation radiotherapy was associated with a significant benefit on overall survival (hazard ratio [HR] 0·94, 95% CI 0·90-0·98; p=0·0033), with an absolute difference at 5 years of 3·1% (95% CI 1·3-4·9) and at 10 years of 1·2% (-0·8 to 3·2). We found a significant interaction (p=0·051) between type of fractionation and treatment effect, the overall survival benefit being restricted to the hyperfractionated group (HR 0·83, 0·74-0·92), with absolute differences at 5 years of 8·1% (3·4 to 12·8) and at 10 years of 3·9% (-0·6 to 8·4). Comparison 2 (conventional fractionation radiotherapy plus concomitant chemotherapy versus altered fractionation radiotherapy alone) included five trials and 986 patients. Overall survival was significantly worse with altered fractionation radiotherapy compared with concomitant chemoradiotherapy (HR 1·22, 1·05-1·42; p=0·0098), with absolute differences at 5 years of -5·8% (-11·9 to 0·3) and at 10 years of -5·1% (-13·0 to 2·8).nnnINTERPRETATIONnThis update confirms, with more patients and a longer follow-up than the first version of MARCH, that hyperfractionated radiotherapy is, along with concomitant chemoradiotherapy, a standard of care for the treatment of locally advanced head and neck squamous cell cancers. The comparison between hyperfractionated radiotherapy and concomitant chemoradiotherapy remains to be specifically tested.nnnFUNDINGnInstitut National du Cancer; and Ligue Nationale Contre le Cancer.


European Journal of Cancer | 2017

Adding abiraterone to androgen deprivation therapy in men with metastatic hormone-sensitive prostate cancer: a systematic review and meta-analysis

Larysa Rydzewska; Sarah Burdett; Claire Vale; Nw Clarke; Karim Fizazi; Thian Kheoh; Malcolm David Mason; Branko Miladinovic; Nicholas D. James; Mahesh K.B. Parmar; Melissa R. Spears; Christopher Sweeney; Matthew R. Sydes; Namphuong Tran; Jayne Tierney

Background There is a need to synthesise the results of numerous randomised controlled trials evaluating the addition of therapies to androgen deprivation therapy (ADT) for men with metastatic hormone-sensitive prostate cancer (mHSPC). This systematic review aims to assess the effects of adding abiraterone acetate plus prednisone/prednisolone (AAP) to ADT. Methods Using our framework for adaptive meta-analysis (FAME), we started the review process before trials had been reported and worked collaboratively with trial investigators to anticipate when eligible trial results would emerge. Thus, we could determine the earliest opportunity for reliable meta-analysis and take account of unavailable trials in interpreting results. We searched multiple sources for trials comparing AAP plus ADT versus ADT in men with mHSPC. We obtained results for the primary outcome of overall survival (OS), secondary outcomes of clinical/radiological progression-free survival (PFS) and grade III–IV and grade V toxicity direct from trial teams. Hazard ratios (HRs) for the effects of AAP plus ADT on OS and PFS, Peto Odds Ratios (Peto ORs) for the effects on acute toxicity and interaction HRs for the effects on OS by patient subgroups were combined across trials using fixed-effect meta-analysis. Findings We identified three eligible trials, one of which was still recruiting (PEACE-1 (NCT01957436)). Results from the two remaining trials (LATITUDE (NCT01715285) and STAMPEDE (NCT00268476)), representing 82% of all men randomised to AAP plus ADT versus ADT (without docetaxel in either arm), showed a highly significant 38% reduction in the risk of death with AAP plus ADT (HR = 0.62, 95% confidence interval [CI] = 0.53–0.71, p = 0.55 × 10−10), that translates into a 14% absolute improvement in 3-year OS. Despite differences in PFS definitions across trials, we also observed a consistent and highly significant 55% reduction in the risk of clinical/radiological PFS (HR = 0.45, 95% CI = 0.40–0.51, p = 0.66 × 10−36) with the addition of AAP, that translates to a 28% absolute improvement at 3 years. There was no evidence of a difference in the OS benefit by Gleason sum score, performance status or nodal status, but the size of the benefit may vary by age. There were more grade III–IV acute cardiac, vascular and hepatic toxicities with AAP plus ADT but no excess of other toxicities or death. Interpretation Adding AAP to ADT is a clinically effective treatment option for men with mHSPC, offering an alternative to docetaxel for men who are starting treatment for the first time. Future research will need to address which of these two agents or whether their combination is most effective, and for whom.


Annals of Oncology | 2018

Adding abiraterone or docetaxel to long-term hormone therapy for prostate cancer: directly randomised data from the STAMPEDE multi-arm, multi-stage platform protocol

Matthew R. Sydes; Melissa R. Spears; M.D. Mason; Nw Clarke; David P. Dearnaley; Johann S. de Bono; G. Attard; Simon Chowdhury; Bill Cross; Silke Gillessen; Zaf Malik; Robert Jones; Chris Parker; A.W.S. Ritchie; J. Martin Russell; Robin Millman; David Matheson; Claire Amos; Clare Gilson; Alison J. Birtle; Susannah Brock; Lisa Capaldi; Prabir Chakraborti; Ananya Choudhury; Linda Evans; Daniel Ford; Joanna Gale; Stephanie Gibbs; Duncan C. Gilbert; Robert Hughes

Abstract Background Adding abiraterone acetate with prednisolone (AAP) or docetaxel with prednisolone (DocP) to standard-of-care (SOC) each improved survival in systemic therapy for advanced or metastatic prostate cancer: evaluation of drug efficacy: a multi-arm multi-stage platform randomised controlled protocol recruiting patients with high-risk locally advanced or metastatic PCa starting long-term androgen deprivation therapy (ADT). The protocol provides the only direct, randomised comparative data of SOCu2009+u2009AAP versus SOCu2009+u2009DocP. Method Recruitment to SOCu2009+u2009DocP and SOCu2009+u2009AAP overlapped November 2011 to March 2013. SOC was long-term ADT or, for most non-metastatic cases, ADT foru2009≥2 years and RT to the primary tumour. Stratified randomisation allocated pts 2 : 1 : 2 to SOC; SOCu2009+u2009docetaxel 75u2009mg/m2 3-weekly×6u2009+u2009prednisolone 10u2009mg daily; or SOCu2009+u2009abiraterone acetate 1000u2009mgu2009+u2009prednisolone 5u2009mg daily. AAP duration depended on stage and intent to give radical RT. The primary outcome measure was death from any cause. Analyses used Cox proportional hazards and flexible parametric models, adjusted for stratification factors. This was not a formally powered comparison. A hazard ratio (HR) <1 favours SOCu2009+u2009AAP, and HRu2009>u20091 favours SOCu2009+u2009DocP. Results A total of 566 consenting patients were contemporaneously randomised: 189 SOCu2009+u2009DocP and 377 SOCu2009+u2009AAP. The patients, balanced by allocated treatment were: 342 (60%) M1; 429 (76%) Gleason 8–10; 449 (79%) WHO performance status 0; median age 66u2009years and median PSA 56u2009ng/ml. With median follow-up 4u2009years, 149 deaths were reported. For overall survival, HRu2009=u20091.16 (95% CI 0.82–1.65); failure-free survival HRu2009=u20090.51 (95% CI 0.39–0.67); progression-free survival HRu2009=u20090.65 (95% CI 0.48–0.88); metastasis-free survival HRu2009=u20090.77 (95% CI 0.57–1.03); prostate cancer-specific survival HRu2009=u20091.02 (0.70–1.49); and symptomatic skeletal events HRu2009=u20090.83 (95% CI 0.55–1.25). In the safety population, the proportion reportingu2009≥1 grade 3, 4 or 5 adverse events ever was 36%, 13% and 1% SOCu2009+u2009DocP, and 40%, 7% and 1% SOCu2009+u2009AAP; prevalence 11% at 1 and 2 years on both arms. Relapse treatment patterns varied by arm. Conclusions This direct, randomised comparative analysis of two new treatment standards for hormone-naïve prostate cancer showed no evidence of a difference in overall or prostate cancer-specific survival, nor in other important outcomes such as symptomatic skeletal events. Worst toxicity grade over entire time on trial was similar but comprised different toxicities in line with the known properties of the drugs. Trial registration Clinicaltrials.gov: NCT00268476.


Annals of Oncology | 2018

What is the optimal systemic treatment of men with metastatic, hormone-naive prostate cancer? A STOPCAP systematic review and network meta-analysis

Claire Vale; Dj Fisher; Ir White; J. Carpenter; Sarah Burdett; Nw Clarke; Karim Fizazi; Gwenaelle Gravis; Nicholas D. James; Malcolm David Mason; Mahesh K.B. Parmar; Larysa Rydzewska; Christopher Sweeney; Melissa R. Spears; Matthew R. Sydes; Jayne Tierney

Abstract Background Our prior Systemic Treatment Options for Cancer of the Prostate systematic reviews showed improved survival for men with metastatic hormone-naive prostate cancer when abiraterone acetate plus prednisolone/prednisone (AAP) or docetaxel (Doc), but not zoledronic acid (ZA), were added to androgen-deprivation therapy (ADT). Trial evidence also suggests a benefit of combining celecoxib (Cel) with ZA and ADT. To establish the optimal treatments, a network meta-analysis (NMA) was carried out based on aggregate data (AD) from all available studies. Methods Overall survival (OS) and failure-free survival data from completed Systemic Treatment Options for Cancer of the Prostate reviews of Doc, ZA and AAP and from recent trials of ZA and Cel contributed to this comprehensive AD-NMA. The primary outcome was OS. Correlations between treatment comparisons within one multi-arm, multi-stage trial were estimated from control-arm event counts. Network consistency and a common heterogeneity variance were assumed. Results We identified 10 completed trials which had closed to recruitment, and one trial in which recruitment was ongoing, as eligible for inclusion. Results are based on six trials including 6204 men (97% of men randomised in all completed trials). Network estimates of effects on OS were consistent with reported comparisons with ADT alone for AAP [hazard ration (HR)u2009=u20090.61, 95% confidence interval (CI) 0.53–0.71], Doc (HRu2009=u20090.77, 95% CI 0.68–0.87), ZAu2009+u2009Cel (HRu2009=u20090.78, 95% CI 0.62–0.97), ZAu2009+u2009Doc (HRu2009=u20090.79, 95% CI 0.66–0.94), Cel (HRu2009=u20090.94 95% CI 0.75–1.17) and ZA (HRu2009=u20090.90 95% CI 0.79–1.03). The effect of ZAu2009+u2009Cel is consistent with the additive effects of the individual treatments. Results suggest that AAP has the highest probability of being the most effective treatment both for OS (94% probability) and failure-free survival (100% probability). Doc was the second-best treatment of OS (35% probability). Conclusions Uniquely, we have included all available results and appropriately accounted for inclusion of multi-arm, multi-stage trials in this AD-NMA. Our results support the use of AAP or Doc with ADT in men with metastatic hormone-naive prostate cancer. AAP appears to be the most effective treatment, but it is not clear to what extent and whether this is due to a true increased benefit with AAP or the variable features of the individual trials. To fully account for patient variability across trials, changes in prognosis or treatment effects over time and the potential impact of treatment on progression, a network meta-analysis based on individual participant data is in development.


European Journal of Cancer | 2018

Response to letter commenting on published paper: Adding abiraterone to androgen deprivation therapy in men with metastatic hormone-sensitive prostate cancer: A systematic review and meta-analysis

Larysa Rydzewska; Sarah Burdett; Claire Vale; Mahesh K.B. Parmar; Jayne Tierney

Our systematic review and meta-analysis was conducted using FAME (Framework for Adaptive Meta-analysis, [1]). This is a prospective approach that takes all eligible trials into account and is responsive to emerging trial results. Thus, we would like to make clear that the review was initiated well in advance of the two trial results being known, and we anticipated that a metaanalysis of these trials would provide both a timely and sufficiently reliable result. It would have been near impossible to predict or expect that the individual trials would produce such ‘overwhelmingly positive’ or ‘remarkably consistent’ results.


Controlled Clinical Trials | 1995

Response to Dr. Blumenstein's letter

Della Gibson; Angela Harvey; Mahesh K.B. Parmar


European Journal of Cancer | 1992

Preoperative radiotherapy in the treatment of cancer of the oesophagus

David J. Girling; Lesley Stewart; Mahesh K.B. Parmar


Controlled Clinical Trials | 1996

Response to O'Rourke

Della Gibson; Angela Harvey; Mahesh K.B. Parmar

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Claire Vale

Medical Research Council

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Jayne Tierney

University College London

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Nw Clarke

University of Salford

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