TCT 2019 – Abbott's aortic valve disappoints
Portico hits noninferiority, but safety looks doubtful. Abbott might want to prioritise a different approach.
The approval trial of Abbott Laboratories’ Portico catheter-based aortic prosthesis disappointed on safety at the weekend, but promising early results with a different technology, the TriClip tricuspid repair product, might be of more use to the company.
Portico will probably still get approved for aortic replacement, but compared against the wildly successful established products – Edwards Lifesciences’ Sapien and Medtronic’s CoreValve – it will likely be an afterthought in terms of sales.
On the threshold
On the surface the pivotal Portico data, presented on Saturday at the TCT meeting in San Francisco, look positive. Portico was noninferior to Sapien and Medtronic’s CoreValve on the primary efficacy endpoint, a composite of mortality and disabling stroke at one year, in 750 extreme and high-risk symptomatic severe aortic stenosis patients (p=0.006).
But this event rate was numerically higher in the Portico arm, at 14.9% versus 13.4% for the commercial valves. This was driven by all-cause mortality, at 14.3% with Portico compared with 12.0% in the control arm. Rates of paravalvular leak, vascular complications and new pacemaker implantation were all also higher in the Portico arm.
The primary safety endpoint, a composite of mortality, stroke, bleeding requiring blood transfusion, acute kidney injury, or major vascular complications at 30 days, was also numerically higher with Portico, at 13.8% versus 9.6% with Sapien and CoreValve.
The rate of leaflet thrombosis was not presented at TCT despite a relatively high rate of this event having caused the trial to be paused for nearly a year from September 2014. These data should emerge next year.
Abbott intends to launch Portico in the US in about a year’s time, but it seems unlikely that the product will pick up much traction against the various valves in the Sapien and CoreValve ranges, which have about 60% and 35% of the global transcatheter aortic replacement market respectively. Current sellside consensus for Portico, as compiled by EvaluateMedTech, has the device selling $97m this year, rising to just $281m in 2024.
If Edwards and Medtronic have the aortic replacement market sewn up, Abbott is holding its own in a different area: the repair of the mitral valve. Its MitraClip device is forecast to have sales of $707m this year, according to EvaluateMedTech’s sellside consensus, and ought to break the $1bn barrier in 2021.
The company’s TriClip tricuspid repair device is, it seems, on the way to joining its cousin on the market following the presentation of six-month safety data from the Triluminate trial. This study hit its efficacy endpoint in the spring, but it was the safety data cardiologists were waiting for (Abbott shifts to tricuspid repair, May 22, 2019).
At six months 3.7% of the 85 patients in the single-arm trial had had a major adverse event, significantly less than the prespecified goal of 39%. These events were two cardiovascular deaths and one new-onset renal failure.
The US approval trial of TriClip is already under way. Triluminate Pivotal will enrol 700 patients with severe regurgitation in spite of previous treatments, and will compare the use of TriClip with drug therapy.
The primary outcome is a composite of all-cause mortality, tricuspid valve surgery, rate of heart failure hospitalisations, and quality of life improvement, and data could emerge in August 2022. As this date approaches it will be interesting to see whether the sellside sees TriClip going the way of MitraClip – or Portico.
|Abbott||Portico||Aortic valve replacement||Portico pivotal trial|
|Boston Scientific||Acurate Neo||Aortic valve replacement||Scope I|
|Abbott||TriClip||Tricuspid valve repair||Triluminate Pivotal|
|Abbott||TriClip||Tricuspid valve repair||Triluminate|