By Bill Berkrot
July 1 (Reuters) - The blood clot preventer Eliquis, sold by Pfizer Inc and Bristol-Myers Squibb Co, proved as effective as widely used warfarin in treating a dangerous condition known as venous thromboembolism and caused far less bleeding, according to data from a large clinical trial.
The Pfizer and Bristol-Myers pill met the main goal of the study by showing it worked just as well as conventional treatment with warfarin, a generic blood thinner, in reducing recurrence of the condition and related deaths.
Eliquis also led to a nearly 70 percent reduction in the risk of major bleeding and more than a 50 percent reduction in a category known as clinically relevant non-major bleeding. Bleeding is typically the most troubling side effect of extended use of blood thinning drugs.
Dr. Giancarlo Agnelli, the study's lead investigator, called the bleeding results "a remarkable real advantage" for Eliquis.
"This is to me the most striking finding of this study in terms of potential changes to clinical practice," Agnelli, who presented the data on Monday at the International Society on Thrombosis and Hemostasis (ISTH) meeting in Amsterdam, said in a telephone interview. The results were also published in the New England Journal of Medicine.
"This really makes apixaban a really safe compound," he added, using the chemical name for Eliquis.
Venous thromboembolism (VTE) is a potentially fatal condition consisting of blood clots in the leg, known as deep vein thrombosis, and clots in the lungs, known as pulmonary embolism. About 900,000 Americans and 1 million patients in the European Union are diagnosed with the condition each year. The condition recurs in up to 10 percent of patients.
SLOW UPTAKE FOR SOME
Eliquis belongs to a new class of blood clot preventers meant to replace warfarin, which has been in use for decades and requires rigorous monitoring. It competes directly with Xarelto from Bayer AG and Johnson & Johnson, and Boehringer Ingelheim's Pradaxa.
Some doctors have been reluctant to switch to the new medicines in part because their blood-thinning effect is not easily reversed in case emergency medical treatment, such as surgery, is needed. Companies are testing agents that could be used to reverse the blood thinning effect if necessary.
Eliquis is already approved to prevent strokes and blood clots in patients with a common, but dangerous irregular heartbeat known as atrial fibrillation - by far the largest market for the new blood thinners.
ISI Group analyst Mark Schoenebaum forecast eventual peak annual sales of $3 billion for the drug. If approved for venous thromboembolism, it would add an important, if smaller, use for the medicine.
While doctors are comfortable using warfarin, it requires careful patient monitoring of levels of the drug in the blood and dose adjustments, as well as patient dietary and lifestyle changes to prevent dangerous bleeding. Eliquis and its rivals are a fixed dose treatment with little or no patient monitoring required.
"Even if you show just non-inferiority, the advantage (of Eliquis) in terms of increased practicality is huge," said Agnelli, the director of the Department of Internal and Cardiovascular Medicine and Stroke-Unit of University Hospital in Perugia, Italy.
The nearly 5,400-patient trial tested 10 milligrams of Eliquis given twice a day for seven days followed by 5 mg twice daily for six months against the conventional use of initial injections of Sanofi's Lovenox (enoxaparin) followed by daily use of warfarin.
For the composite goal of recurrence of VTE and VTE-related death there were 59 cases for Eliquis, or 2.3 percent, versus 71 cases for warfarin, or 2.7 percent.
For the primary safety goal of the study, there were 15 reports of major bleeding among Eliquis patients, or 0.6 percent, compared with 49 major bleeds among warfarin patients, or 1.8 percent. The 69-percent reduced major bleeding risk was deemed to be highly statistically significant, researchers said.
There were 103 reported cases of clinically relevant non-major bleeding with the Pfizer and Bristol drug versus 215 cases in the warfarin group, or a risk reduction of 52 percent.