December 7, 2017

expert reaction to paper looking at vaginal mesh product regulation

The BMJ has published a new study from scientists examining vaginal mesh product regulation.

John Wilkinson, MHRA Director of Devices said:

“Patient safety is our highest priority and we recognise some women do develop serious complications which can be very significant for the affected women.  We also know many women gain benefit from these surgical procedures for what can be extremely debilitating conditions.

“We continue to work closely with NHS England, NICE and professional bodies, and we are all committed to helping address the serious concerns raised by women who have experienced complications.

“We actively encourage patients and healthcare professionals to report complications associated with these implants through the Yellow Card scheme.”

Prof. Cathryn Glazener, retired Emeritus Professor at the Health Services Research Unit, University of Aberdeen, said:

“This paper unfortunately confuses the issue of mesh tapes for incontinence with mesh implants for prolapse.  The two conditions are different and the evidence is different too.  If the evidence is conflated women may be at risk of being misled.  Mesh tapes are as effective, and safer in the short term, than the main non-mesh alternative, while long-term complications are similar¹.  In contrast, mesh surgery for bladder or bowel prolapse may be no more, or less, effective than non-mesh prolapse repair, but does lead to more long term complications^1,2. Ultimately it must be up to the woman to choose on the basis of full and reliable evidence, especially about risk.

“I do agree with the authors of the article, however, that regulation of new device use needs to be tightened up, in line with the much more rigorous scrutiny already in place for new drugs.”

1 Morling 2017 ‘Adverse events after first, single, mesh and non-mesh surgical procedures for stress urinary incontinence and pelvic organ prolapse in Scotland, 1997–2016: a population-based cohort study’, Joanne R Morling et al, The Lancet, Vol. 389, No. 10069, p629–640, December 20, 2016.  http://www.isdscotland.org/whats-new/Stress-Urinary-Incontinence-and-Pelvic-Organ-Prolapse/

2 Glazener 2017 ‘Mesh, graft, or standard repair for women having primary transvaginal anterior or posterior compartment prolapse surgery: two parallel-group, multicentre, randomised, controlled trials (PROSPECT)’, Cathryn MA Glazener et al (the PROSPECT study group), The Lancet, Vol. 389, No. 10067, p381–392, December 20, 2016

Prof. Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene & Tropical Medicine, said:

“The regulation of medical devices is much less developed than the regulation of medicines.  The almost universal requirement for introduction of medicines or vaccines to have randomised trials showing evidence of clinical benefit (at least in a surrogate for benefit) is not mirrored in requirements for devices.  The absence of good trials for these vaginal meshes, which has been investigated carefully by these authors, shows the problem clearly.

“Devices are frequently used lifelong (breast implants, joint replacements, cardiac pacemakers etc.).  The consequence is that the trials need to be long-term.  The suggestion from the authors of this paper for ‘provisional licenses’ to be given to new devices, coupled with careful post-marketing monitoring, seems to be entirely sensible.  Reliance just on ‘spontaneous reports’ of adverse events is inadequate both for devices and medicines.  The available data for post-marketing studies in medicines are also more extensive and more carefully utilised than for devices.  It is clearly expensive to have long-term trials and could also lead to delay in the introduction of new effective devices, but the assumption that new means better is not always true.

“Changes in regulation are often driven by lessons learnt from very bad situations (such as thalidomide), and the need for change in regard to devices is clear.  The US FDA seems to have made better assessments, as noted by the authors, and they seem to be more active in the use of better quality post-marketing data for monitoring safety of devices.”

* ‘Transvaginal mesh failure: lessons for regulation of implantable devices’ by Carl Heneghan et al. published in the BMJ on Thursday 7 December 2017.

Declared interests

Prof. Cathryn Glazener: “Original Chief Investigator of PROSPECT; contributed to the MHRA review; member of the Scottish Independent Review.”

Prof. Stephen Evans: “I have been a colleague of one of the authors (BG) and know another author well (JA).  I was at one time (over twenty years ago) an advisor to the UK Medical Devices Agency, but resigned, partly over concerns at the absence of clinical trials in devices prior to their being approved for marketing.”