- A cardiovascular drug from biotechnology company Idorsia failed to meet its main goal in an important clinical trial, sending shares in the drugmaker down by about 15% in Monday trading on the Swiss stock exchange.
- The trial found the drug, called clazosentan, did not prevent decline due to cerebral ischemia in adults who had recently experienced life-threatening bleeding in the brain. In a statement, Idorsia described the finding as an “unexpected result,” and said it would work to fully analyze the study data and publish it in “due course.”
- Clazosentan is currently marketed in Japan, where it’s sold under the brand name Pivlaz. Idorsia ran the study that’s now read out negative results to support potential approval in other countries, such as the U.S. and in Europe.
Idorsia is the byproduct of Johnson & Johnson’s 2017 deal to acquire the Swiss drugmaker Actelion. As part of the buyout, Actelion’s drug discovery and early R&D work was spun out into a new biotech company run by former Actelion CEO Jean-Paul Clozel.
Idorsia has since built itself into a commercial-stage company, with clazosentan cleared for use in Japan and another drug, Quviviq, approved in the U.S. and Europe. Idorsia is seeking the Food and Drug Administration’s OK for a third, aprocitentan, as a treatment for difficult-to-control high blood pressure.
But its drug development plans hit a snag with Monday’s readout of the clazosentan study, known as REACT. The trial, which enrolled just over 400 participants from sites in the U.S., Canada and Europe, assessed Idorsia’s drug for use after a dangerous condition called aneurysmal subarachnoid hemorrhage, in which a ruptured aneurysm causes bleeding in the brain.
The hemorrhage is usually treated with one of two surgical procedures. But the bleeding can result in the release of a compound called endothelin-1 that leads arteries in the brain to narrow. With diminished blood flow, patients can then experience dangerous cerebral ischemia. Clazosentan is meant to interrupt that cascade of events by inhibiting what’s known as the endothelin A receptor.
However, in REACT, treatment with Idorsia’s drug did not work significantly better than a placebo in preventing clinical decline due to delayed cerebral ischemia. The company did not disclose specific results.
“I am very disappointed with the negative result of REACT,” said Idorsia CEO Clozel. “The study was based on strong scientific and medical rationale and executed diligently by a committed team of experts at Idorsia and by the investigators.”
Clozel had previously noted REACT’s importance on an October conference call, indicating the study’s result would shape clazosentan’s prospects for market expansion and greater sales.
Clazosentan’s approval in Japan was based on two prior Phase 3 studies. Data from one, called CONSCIOUS-2, showed the drug dose was too low to result in a statistically significant treatment effect on morbidity and all-cause mortality, leading the company to stop the second study early.
A follow-up analysis of data from that second trial indicated a higher dose reduced morbidity and mortality risk, according to Idorsia.
Idorsia started selling clazosentan in Japan last April and has said the launch is progressing well. It’s not clear what effect the REACT study results would have on Pivlaz’s market authorization.