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|Portola, Bristol-Myers Squibb and Pfizer Announce Full Results of Second Part of Phase 3 ANNEXA-A(TM) Study Demonstrating That Investigational Andexanet Alfa Sustained Reversal of Anticoagulant Effect of Factor Xa Inhibitor Eliquis (apixaban)|
SOUTH SAN FRANCISCO, Calif., PRINCETON, N.J. and NEW YORK,
This second part of the study achieved all primary and pre-specified secondary endpoints with high statistical significance. Andexanet alfa produced rapid reversal of the anticoagulant effect of Eliquis, as measured by anti-Factor Xa activity, which was sustained for the duration of the infusion. Andexanet alfa significantly reduced the level of free unbound Eliquis in the plasma and restored thrombin generation to normal. Andexanet alfa was well tolerated, with no serious adverse events, thrombotic events, or antibodies to Factor X or Xa reported. Mild infusion reactions were reported in six subjects: four in the andexanet arm and two in the placebo arm. No subjects discontinued the study due to an adverse event. The full data set was presented today in a Late-Breaking Clinical Trial oral session at the
"These Phase 3 findings demonstrate that andexanet alfa can rapidly reverse anticoagulant activity for a short or sustained period of time and that anticoagulant activity can be reinitiated following discontinuation of the infusion. This is significant given different clinical needs for shorter-duration or longer-duration reversal," said John T. Curnutte, M.D., Ph.D., executive vice president, research and development, for Portola. "Importantly, our trial endpoints are based on the accepted pharmacodynamic measurements of anticoagulant activity agreed to with regulatory authorities and serve as the basis for our accelerated approval pathway. The results to date across our Phase 2 and Phase 3 andexanet alfa studies with both oral and injectable Factor Xa inhibitors suggest that andexanet alfa is the only investigational reversal agent to clinically show meaningful reversal of Factor Xa anticoagulant activity. There is an increasing number of patients on Factor Xa inhibitors who may need their anticoagulant reversed because they are bleeding or require surgery."
"Bristol-Myers Squibb and Pfizer are committed to continuing to deliver innovative therapies to patients and are pleased with the positive results of both parts of the ANNEXA-A study," said Rory O'Connor, M.D., senior vice president and head of Global Medical Affairs, Global Innovative Pharmaceuticals Business,
"We are proud to share in the presentation of this ANNEXA-A Part 2 study data," said Douglas Manion, M.D., head of specialty development, Bristol-Myers Squibb. "As we saw in Part 1, these results demonstrate that andexanet alfa could prove to be an effective reversal agent for Eliquis."
Portola plans to submit data from the ANNEXA-A (apixaban) and ANNEXA-R (rivaroxaban) studies, and initial data from a Phase 4 study, as part of its Biologics License Application (BLA) to the FDA under an Accelerated Approval pathway by the end of 2015.
ANNEXA-A Study Design
The randomized, double-blind, placebo-controlled Phase 3 ANNEXA-A study evaluated the safety and efficacy of andexanet alfa in reversing apixaban-induced anticoagulation in older healthy volunteers ages 50-75 years. Efficacy was evaluated using biomarker endpoints, with anti-Factor Xa levels as the primary endpoint. Secondary endpoints included plasma levels of free unbound apixaban and endogenous thrombin potential (ETP), a measure of thrombin generation.
In ANNEXA-A Part 1, 33 healthy volunteers were given apixaban 5 mg twice daily for four days and then randomized in a 3:1 ratio to andexanet alfa administered as a 400 mg IV bolus (n=24) or to placebo (n=9). In the second part of the study, 31 healthy volunteers were given apixaban 5 mg twice daily for four days and then randomized in a 3:1 ratio to andexanet alfa administered as a 400 mg IV bolus followed by a continuous infusion of 4 mg/min for 120 minutes (n=23) or to placebo (n=8).
ANNEXA-A Study Part 2 Results
Results showed that, following the administration of a bolus of andexanet alfa, the anticoagulant activity of apixaban, as measured by anti-Factor Xa activity, was reversed by 93.5 percent (p<0.0001). Following completion of the two-hour continuous infusion of andexanet alfa, the anticoagulant activity of apixaban remained significantly reversed, by 92.7 percent (p<0.0001). These two endpoints demonstrate that andexanet alfa infusion was able to keep anti-Factor Xa levels flat from the end of the bolus (93.5 percent) to the end of the two-hour infusion (92.7 percent).
Additional secondary endpoints showed:
No serious adverse events, thrombotic events, or antibodies to Factor X or Xa were reported following andexanet alfa administration. Mild infusion reactions were reported in six subjects.
No subjects discontinued the study due to an adverse event.
Addressing the Absence of a Factor Xa Inhibitor Antidote
Currently, millions of patients are treated with Factor Xa inhibitors for short-term use or chronic conditions, and the anticoagulant market is expected to continue to grow. Recent patient data confirm earlier clinical trial results showing that, annually, between 1 to 4 percent of patients treated with Factor Xa inhibitors may experience major bleeding and an additional 1 percent may require emergency surgery. Development of a specific antidote designed to reverse the anticoagulant activity of Factor Xa inhibitors may provide an important treatment option for patients who experience a major bleeding event or require emergency surgery.
About Andexanet Alfa
Andexanet alfa is a modified human Factor Xa molecule that acts as a decoy to target and sequester with high specificity both oral and injectable Factor Xa inhibitors in the blood. Once bound, the Factor Xa inhibitors are unable to bind to and inhibit native Factor Xa, thus allowing for the restoration of normal hemostatic processes. Andexanet alfa has the potential to address numerous clinical scenarios where an antidote is needed by allowing for flexible and controlled reversal. This can be short-acting through the administration of an IV bolus or longer-acting with the addition of an extended infusion.
Andexanet alfa is the only compound being studied as a reversal agent for Factor Xa inhibitors that directly and specifically corrects anti-Factor Xa activity, the anticoagulant mechanism of these agents.
Andexanet alfa has been granted orphan drug designation by the FDA for reversing the anticoagulant effect of direct or indirect Factor Xa inhibitors in patients experiencing a serious uncontrolled bleeding event or who require urgent or emergent surgery.
Eliquis (apixaban) is an oral selective Factor Xa inhibitor. By inhibiting Factor Xa, a key blood-clotting protein, Eliquis decreases thrombin generation and blood clot formation. Eliquis is approved for multiple indications in the U.S. based on efficacy and safety data, including results from seven Phase 3 clinical trials. Eliquis is a prescription medicine indicated to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation; for the prophylaxis of deep vein thrombosis (DVT), which may lead to pulmonary embolism (PE), in patients who have undergone hip or knee replacement surgery; for the treatment of DVT and PE; and to reduce the risk of recurrent DVT and PE following initial therapy.
ELIQUIS Indications and Important Safety Information
ELIQUIS is indicated to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation.
ELIQUIS is indicated for the prophylaxis of deep vein thrombosis (DVT), which may lead to pulmonary embolism (PE), in patients who have undergone hip or knee replacement surgery.
ELIQUIS is indicated for the treatment of DVT and PE, and to reduce the risk of recurrent DVT and PE following initial therapy.
ELIQUIS Important Safety Information
WARNING: (A) PREMATURE DISCONTINUATION OF ELIQUIS INCREASES THE RISK OF THROMBOTIC EVENTS, (B) SPINAL/EPIDURAL HEMATOMA
Monitor patients frequently for signs and symptoms of neurological impairment. If neurological compromise is noted, urgent treatment is necessary.
WARNINGS AND PRECAUTIONS
TEMPORARY INTERRUPTION FOR SURGERY AND OTHER INTERVENTIONS
PREGNANCY CATEGORY B
Portola's wholly-owned, oral, once-daily Factor Xa inhibitor betrixaban is being evaluated in the only biomarker-based Phase 3 study for hospital-to-home prophylaxis of venous thromboembolism (VTE) in acute medically ill patients. Betrixaban's distinct properties may have the potential to allow the agent to demonstrate efficacy without the significant increase in the rate of major bleeding that was seen in this patient population with other Factor Xa inhibitors. If approved, betrixaban could be the first anticoagulant for both hospital and post-discharge VTE prophylaxis and the standard of care in this large market of more than 20 million patients in the G7 countries alone.
Andexanet alfa, an FDA-designated breakthrough therapy, is a recombinant protein designed to reverse the anticoagulant effect in patients treated with an oral or injectable Factor Xa inhibitor. Andexanet alfa has the potential to be a first-in-class antidote for anticoagulated patients who suffer a major bleeding episode or require emergency surgery. Portola has entered into Phase 3 clinical collaboration agreements with all of the manufacturers of direct Factor Xa inhibitors while retaining all commercial rights to andexanet alfa. The Company is currently evaluating andexanet alfa in the Phase 3 and Phase 4 ANNEXA™ (Andexanet Alfa a Novel Antidote to the Anticoagulant Effects of FXa Inhibitors) registration studies.
Portola's product candidate in the area of hematologic cancer, cerdulatinib, is an orally available molecule that uniquely inhibits two validated tumor proliferation pathways – spleen tyrosine kinase (Syk) and janus kinase (JAK). It is currently being evaluated in a Phase 1/2a proof-of-concept study in patients with B cell leukemias or lymphomas with a focus on genetically-defined subtypes, as well as in patients who have failed therapy due to relapse or acquired mutations.
About Bristol-Myers Squibb
Bristol-Myers Squibb is a global biopharmaceutical company whose mission is to discover, develop and deliver innovative medicines that help patients prevail over serious diseases. For more information, please visit http://www.bms.com or follow us on Twitter at http://twitter.com/bmsnews.
At Pfizer, we apply science and our global resources to bring therapies to people that extend and significantly improve their lives. We strive to set the standard for quality, safety and value in the discovery, development and manufacture of health care products. Our global portfolio includes medicines and vaccines as well as many of the world's best-known consumer health care products. Every day, Pfizer colleagues work across developed and emerging markets to advance wellness, prevention, treatments and cures that challenge the most feared diseases of our time. Consistent with our responsibility as one of the world's premier innovative biopharmaceutical companies, we collaborate with health care providers, governments and local communities to support and expand access to reliable, affordable health care around the world. For more than 150 years, Pfizer has worked to make a difference for all who rely on us. To learn more, please visit us at www.pfizer.com.
Portola Forward-Looking Statement
Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Such statements include, but are not limited to, statements regarding: Portola's plans for future clinical studies and pursuit of an Accelerated Approval process for andexanet alfa, anticipated growth in the market for anticoagulants, the potential indications, efficacy, safety and activity of andexanet alfa, and the potential market and indications for its other product candidates. Risks that contribute to the uncertain nature of the forward-looking statements include: the accuracy of Portola's estimates regarding its ability to initiate and/or complete its clinical trials; the success of Portola's clinical trials and the demonstrated efficacy of Portola's product candidates thereunder; the accuracy of Portola's estimates regarding its expenses and capital requirements; Portola's ability to manufacture andexanet alfa; regulatory developments in the United States and foreign countries; Portola's ability to obtain and maintain intellectual property protection for its product candidates; and the loss of key scientific or management personnel. These and other risks and uncertainties are described more fully in Portola's most recent filings with the
Bristol-Myers Squibb Forward-Looking Statement
This press release contains "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995 regarding product development. Such forward-looking statements are based on current expectations and involve inherent risks and uncertainties, including factors that could delay, divert or change any of them, and could cause actual outcomes and results to differ materially from current expectations. No forward-looking statement can be guaranteed. Forward-looking statements in this press release should be evaluated together with the many uncertainties that affect Bristol-Myers Squibb's business, particularly those identified in the cautionary factors discussion in Bristol-Myers Squibb's Annual Report on Form 10-K for the year ended
Pfizer Disclosure Notice
The information contained in this release is as of
This release contains forward-looking information about Eliquis and andexanet alfa, including their potential benefits, that involves substantial risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. Risks and uncertainties include, among other things, the uncertainties inherent in research and development, including the possibility of unfavorable clinical trial results, including unfavorable new clinical data and additional analyses of existing clinical data; whether and when any BLA may be filed for andexanet alfa; whether and when regulatory authorities will approve any such BLA; and competitive developments.
A further description of risks and uncertainties can be found in Pfizer's Annual Report on Form 10-K for the fiscal year ended
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