Regulatory approval review of transcatheter mitral valve repair - Difference in the indication between the USA and Japan

Abstract

The indication for MitraClip (Abbott Vascular, Santa Clara, CA, USA) in the USA is degenerative mitral regurgitation (DMR), but the Japanese indication includes both DMR and functional mitral regurgitation (FMR), in patients without severe left ventricular dysfunction. One of the reasons for this difference is that the Japanese Circulation Society submitted a formal request to the Japanese government for early approval of MitraClip for both DMR and FMR on the basis of unmet medical need for MR patients resistant to medical therapy, but at prohibitive risk for mitral valve surgery. Here, we describe the regulatory approval review process of MitraClip in Japan. Clinical data from outside Japan indicated that MitraClip provides significant improvements from baseline in New York Heart Association Class and hospitalizations for heart failure due to the reduction of MR grade without adversely affecting long-term prognosis in FMR patients as well as DMR patients. Also, a Japanese domestic trial showed a favorable acute procedural success rate without serious adverse events with MitraClip in both DMR and FMR patients. Further, it is considered in Japan that improvement of MR mechanically is clinically important in both DMR and FMR, in patients without severe left ventricular dysfunction. On the basis of these considerations, the MitraClip was approved in Japan for indications of both DMR and FMR with preserved cardiac function in patients at prohibitive risk for mitral valve surgery.

Keywords: Functional mitral regurgitation; MitraClip; Regulatory approval review.