Refining the definition of mandibular osteoradionecrosis in clinical trials: The cancer research UK HOPON trial (Hyperbaric Oxygen for the Prevention of Osteoradionecrosis)

Introduction:Mandibular osteoradionecrosis (ORN) is a common and serious complication of head andneck radiotherapy for which there is little reliable evidence for prevention or treatment. The diagnosisand classification of ORN have been inconsistently and imprecisely defined, even in clinical trials.Methods:A systematic review of diagnosis and classifications of ORN with specific focus on clinical trialsis presented. The most suitable classification was evaluated for consistency using blinded independentreview of outcome data (clinical photographs and radiographs) in the HOPON trial.Results:Of 16 ORN classifications found, only one (Notani) appeared suitable as an endpoint in clinicaltrials. Clinical records of 217 timepoints were analysed amongst 94 randomised patients in theHOPON trial. The only inconsistency in classification arose where minor bone spicules (MBS) were appar-ent, which occurred in 19% of patients. Some trial investigators judged MBS as clinically unimportant andnot reflecting ORN, others classified as ORN based on rigid definitions in common clinical use. When MBSwas added as a distinct category to the Notani classification this ambiguity was resolved and agreementbetween observers was achieved.Discussion:Most definitions and clinical classifications are based on retrospective case series and may beunsuitable for prospective interventional trials of ORN prevention or treatment. When ORN is used as aprimary or secondary outcome in prospective clinical trials, the use of Notani classification with the addi-tional category of MBS is recommended as it avoids subjectivity and enhances reliability and consistencyof reporting

Activity of eribulin mesylate in heavily pretreated breast cancer granted accessvia the Cancer Drugs Fund

Aim: Eribulin mesylate is a synthetic analog of halichondrin B and is licensed for the treatment of patients with locally advanced or metastatic breast cancer that has progressed following treatment with anthracyclines and taxanes. It was not deemed to be cost effective based on a cost analysis by the National Institute for Health and Care Excellence in England and therefore it is not funded routinely by the National Health Service. The establishment of the Cancer Drugs Fund in England subsequently enabled access. As with any new chemotherapy drug that enters clinical practice for metastatic breast cancer (MBC) it is often used in heavily pretreated patients and the experience in a routine clinical setting can differ from that in a clinical study. We therefore present the experience of the first 25 cases treated at our institution via the Cancer Drugs Fund. Materials & methods: A total of 25 patients were treated and in the 22 assessable cases the objective response rate was 18% (four out of 22), with a clinical benefit rate of 41.0% (9 out of 22). Results: The median time-to-progression and overall survival were 4.08 months and 5.89 months, respectively. There was a significant difference in clinical benefit rate (odds ratio: 0.065; 95% CI: 0–0.529; p = 0.0055), as well as time-to-progression (hazard ratio: 9.18; 95% CI: 2.26–37.38; p = 0.002 adjusted for age at diagnosis and interval between initial MBC diagnosis and commencing eribulin) favoring those patients who had not been rechallenged. There was no significant difference in overall survival (hazard ratio: 1.16; 95% CI: 0.44–3.05; p = 0.770 adjusted for age at diagnosis and interval between initial diagnosis of MBC and commencing eribulin). Conclusion: Eribulin mesylate shows clinical activity; however, there appears to be differences in terms of benefit in patients based on whether patients have been rechallenged with an anthracycline and/or a taxane. These data require confirmation in larger patient groups

Spatial effects should be allowed for in primary care and other community-based cluster RCTS

<p>Abstract</p> <p>Background</p> <p>Typical advice on the design and analysis of cluster randomized trials (C-RCTs) focuses on allowance for the clustering at the level of the unit of allocation. However often C-RCTs are also organised spatially as may occur in the fields of Public Health and Primary Care where populations may even overlap.</p> <p>Methods</p> <p>We allowed for spatial effects on the error variance by a multiple membership model. These are a form of hierarchical model in which each lower level unit is a member of more than one higher level unit. Membership may be determined through adjacency or through Euclidean distance of centroids or in other ways such as the proportion of overlapping population. Such models may be estimated for Normal, binary and Poisson responses in Stata (v10 or above) as well as in WinBUGS or MLWin. We used this to analyse a dummy trial and two real, previously published cluster-allocated studies (one allocating general practices within one City and the other allocating general practices within one County) to investigate the extent to which ignoring spatial effects affected the estimate of treatment effect, using different methods for defining membership with Akaike's Information Criterion to determine the "best" model.</p> <p>Results</p> <p>The best fitting model included both a fixed North-South gradient and a random cluster effect for the dummy RCT. For one of the real RCTs the best fitting model included both a random practice effect plus a multiple membership spatial term, while for the other RCT the best fitting model ignored the clustering but included a fixed North-South gradient. Alternative models which fitted only slightly less well all included spatial effects in one form or another, with some variation in parameter estimates (greater when less well fitting models were included).</p> <p>Conclusions</p> <p>These particular results are only illustrative. However, we believe when designing C-RCTs in a primary care setting the possibility of spatial effects should be considered in relation to the intervention and response, as well as any explanatory effect of fixed covariates, together with any implications for sample size and methods for planned analyses.</p

P3MC: A double blind parallel group randomised placebo controlled trial of Propranolol and Pizotifen in preventing migraine in children

<p>Abstract</p> <p>Background</p> <p>A recent Cochrane Review demonstrated the remarkable lack of reliable clinical trials of migraine treatments for children, especially for the two most prescribed preventative treatments in the UK, <it>Propranolol </it>and <it>Pizotifen</it>.</p> <p>Migraine trials in both children and adults have high placebo responder rates, e.g. of 23%, but for a trial's results to be generalisable "placebo responders" should not be excluded and for a drug to be worthwhile it should be clearly superior, both clinically and statistically, to placebo.</p> <p>Methods/Design</p> <p>Two multicentre, two arm double blind parallel group randomised controlled trials, with allocation ratio of 2:1 for each comparison, Propranolol versus placebo and Pizotifen versus placebo. The trial is designed to test whether Propranolol is superior to placebo and whether Pizotifen is superior to placebo for the prevention of migraine attacks in children aged 5 - 16 years referred to secondary care out-patient settings with frequent migraine (2-6/4 weeks). The primary outcome measure is the number of migraine attacks during trial weeks 11 to 14.</p> <p>Discussion</p> <p>A strength of this trial is the participation of clinically well defined migraine patients who will also be approached to help with future longer-term follow-up studies.</p> <p>Trial Registration</p> <p>ISRCTN97360154</p

HOPON (Hyperbaric Oxygen for the Prevention of Osteoradionecrosis): a randomised controlled trial of hyperbaric oxygen to prevent osteoradionecrosis of the irradiated mandible: study protocol for a randomised controlled trial

Background: Osteoradionecrosis of the mandible is the most common serious complication of radiotherapy for head and neck malignancy. For decades, hyperbaric oxygen has been employed in efforts to prevent those cases of osteoradionecrosis that are precipitated by dental extractions or implant placement. The evidence for using hyperbaric oxygen remains poor and current clinical practice varies greatly. We describe a protocol for a clinical trial to assess the benefit of hyperbaric oxygen in the prevention of osteoradionecrosis during surgery on the irradiated mandible. Methods/design: The HOPON trial is a phase III, randomised controlled, multi-centre trial. It employs an unblinded trial design, but the assessment of the primary endpoint, i.e. the diagnosis of osteoradionecrosis, is assessed on anonymised clinical photographs and radiographs by a blinded expert panel. Eligibility is through the need for a high-risk dental procedure in the mandible where at least 50-Gy radiotherapy has been received. Patients are randomised 1:1 to hyperbaric oxygen arm (Marx protocol) : control arm, but both groups receive antibiotics and chlorhexidine mouthwash. The primary endpoint is the presence of osteoradionecrosis at 6 months following surgery, but secondary endpoints include other time points, acute symptoms and pain, quality of life, and where implants are placed, their successful retention. Discussion: The protocol presented has evolved through feasibility stages and through analysis of interim data. The classification of osteoradionecrosis has undergone technical refinement to ensure that robust definitions are employed. The HOPON trial is the only multi-centre RCT conducted in this clinical setting despite decades of use of hyperbaric oxygen for the prevention of osteoradionecrosis. Trial registration: European Clinical Trials Database, ID: EudraCT200700622527. First registered on 5 November 2007