Verteporfin photodynamic therapy for neovascular age-related ...

DOI: 10.3310/hta16060Health Technology Assessment 2012; Vol. 16: No. 677Chapter 9ConclusionsThe most notable finding of the VPDT cohort study was that a visual outcome comparableto that reported in the licensing trial was achieved, although we may have underestimatedBCVA deterioration at 1 year because of attrition. This visual outcome was achieved despite aconsiderably lower retreatment frequency. This finding highlights that treatment regimens thatreceive marketing authorisation may overestimate the intensity of treatment required. Similarquestions have arisen in the last 5 years about other technologies, for example the duration oftreatment with Herceptin ® (Roche) that women require after primary surgery and chemotherapyto achieve the benefits seen in licensing trials.The VPDT study clearly showed that the small beneficial differences in BCVA between thetreatment and control groups in the TAP licensing trials would translate into small gains ingeneric and vision-specific HRQoL and that the cost of achieving these outcomes was similarto the largest previously published estimate. The associations between BCVA and HRQoL, andbetween BCVA and HSS costs, represent an enduring legacy of the VPDT cohort study that arelikely to be applicable to future evaluations of interventions to treat nAMD.Even though VPDT is no longer the first line of treatment for nAMD, our findings continueto have relevance to clinical practice. In particular, the quantification of the influence of keycovariates of age, cigarette smoking and status of the fellow eye on the trajectory of vision losshas added to our knowledge and suggests that these factors should be considered in the designand analysis of trials of treatments for nAMD. The findings will also continue to be of relevanceand provide a reference framework for the estimation of cost-effectiveness in future trials andtechnology appraisals.The future role of studies like the VPDT cohort study needs to considered carefully. Theauthorities that desired the VPDT cohort study did not state its purpose clearly in advanceof commissioning the study, unlike other research commissioned by the National Institutefor Health Research. For example, there was ambiguity in the wider health community aboutwhether the study was being set up (a) to allow selected ophthalmologists, with the resources toparticipate, to treat patients with predominantly classic CNV lesions or (b) to provide a vehicle toallow such patients to receive treatment given the guidance by NICE. Despite a strong desire bythe authorities for the study to achieve its aim of providing a quality-controlled implementationof VPDT, this was not matched by unequivocal guidance to commissioners, designated hospitalsand ophthalmologists that participation was not voluntary. This lack of direction meant thatthe flow of resources needed to carry out the study at a participating site was perceived to bediscretionary by some PCTs and hospital managers. Some ophthalmologists were also hostileto the study despite strong support from the Royal College of Ophthalmologists. If in the futurethe introduction of a new technology is made contingent on undertaking postlicensing datacollection and research, a more explicit commitment from commissioners and policy-makersis needed.The model of the VPDT cohort study can be used to meet the many needs of the NHS whenconsidering how to implement an expensive therapy, for example provision of the educationand training required to implement the therapy, treatment protocols to assure the quality oftreatment, infrastructure for auditing implementation through standardised data acquisition© Queen’s Printer and Controller of HMSO 2012. This work was produced by Reeves et al. under the terms of a commissioning contract issued by theSecretary of State for Health.