Shares of HeartWare International Inc. (NSDQ:HTWR) rose nearly 5 percent today after an update on a bridge-to-transplant trial of its implantable heart pump showed 93 percent of the 241 patients survived for at least six months after receiving the device.
The Framingham, Mass.-based firm presented the results from the Advance BTT study and its continued access protocol arm at the European Assn. for Cardio-Thoracic Surgery’s annual meeting in Lisbon.
The patients in the trial – 140 from Advance and another 101 with at least six months follow-up – are part of HeartWare’s investigational device exemption from the FDA to study the device as a temporary bridge for patients awaiting a heart transplant.
"Consistent with previously presented data from this study, we observed high survival rates for patients through the six-month endpoint, and particularly low observed rates for bleeding and infection," said principal investigator Dr. Mark Slaughter in prepared remarks. "Adjustments in anticoagulation are contributing to reduced thrombus events, and overall adverse event rates remain low despite increased exposure to the device due to higher survival and a lower transplant rate."
The reduced thrombus events Slaughter cited are likely mollifying some Wall Street investors who were spooked by a higher-than-expected rate of blood clots in the trial. That update sent shares down 15 percent in mid-April.
Today HeartWare said only 0.03 percent of patients in the trial needed to have a pump replaced for suspected thrombus, down "since an adjustment in anticoagulation in March," according to a press release.
The company is also enrolling patients for a 450-patient study of the HVAD pump as a so-called "destination therapy" for patients too sick or otherwise ineligible for a heart transplant. Once enrollment wraps up by mid-2012, the company hopes, those patients will be tracked for two years post-implantation.
HeartWare is on the short list of potential acquisitions by Swiss investment bank UBS, along with rivals Thoratec Corp. (NSDQ:THOR) and Abiomed (NSDQ:ABMD). One potential acquirer is Johnson & Johnson (NYSE:JNJ), which has expressed interest in the cardiac assist device space in recent weeks.
HTWR shares closed at $67.46 today, up 4.7 percent from yesterday’s close.