Orexigen Announces Allowance of New U.S. Patent for Contrave®

SAN DIEGO -- Orexigen Therapeutics, Inc. announced that the Company has received a notice of allowance from the U.S. Patent and Trademark Office (PTO) for U.S. Patent Application No. 11/757,773, which covers use of Orexigen's sustained release formulation of naltrexone, which was designed to improve drug tolerability for Contrave® (naltrexone HCl / bupropion HCl extended release), in a method for treating obesity. The patent is expected to expire in March of 2028. Orexigen expects the patent to be listed in the Orange Book maintained by the United States Food and Drug Administration.

"A key component of Orexigen's strategy is to strengthen and extend intellectual property protection for Contrave," said Michael Narachi, CEO of Orexigen. "We are pleased that patent protection for use of this naltrexone formulation - and for Contrave - is now expected to extend at least to 2028."

Intellectual Property Protecting Contrave

Contrave is currently protected by U.S. patent number 7,375,111 and U.S. patent number 7,462,626, which Orexigen refers to collectively as the Weber/Cowley patents and which are expected to expire in 2025/2024. The Weber/Cowley patents cover the current composition of Contrave and methods of administering it to treat obesity. Orexigen and/or licensors have filed a number of international counterparts to the Weber/Cowley patents in foreign countries. A European counterpart application to the Weber/Cowley patent has issued in the European Patent Office, or EPO, and provides protection for Mysimba™ (naltrexone HCl / bupropion HCl prolonged release) in the various EPO countries in which the patent has been registered. Orexigen has also filed patent applications, directed to various treatment and formulation aspects of Contrave, in the United States and certain foreign countries under the Patent Cooperation Treaty, or PCT. Use of Contrave for the treatment of insulin resistance is protected by U.S. patent number 8,815,889, which is expected to expire in 2024. A proprietary tri-layer Contrave tablet and its use for weight loss are protected in the United States by U.S. patent numbers 8,088,786 and 8,318,788, which are expected to expire in February 2029 and November 2027, respectively. In addition, the dose escalation schedule of Contrave is protected by U.S. patent 8,722,085, which is expected to expire in November 2027. Orexigen has filed other patent applications in the United States and other parts of the world with the potential, if the patents issue, to extend intellectual property protection to 2034.

Important Safety Information for Contrave (naltrexone HCl and bupropion HCl)

CONTRAVE is not approved for use in the treatment of major depressive disorder or other psychiatric disorders. CONTRAVE contains bupropion, the same active ingredient as some other antidepressant medications (including, but not limited to, WELLBUTRIN, WELLBUTRIN SR, WELLBUTRIN XL and APLENZIN). Antidepressants increased the risk of suicidal thoughts and behavior in children, adolescents, and young adults in short-term trials. These trials did not show an increase in the risk of suicidal thoughts and behavior with antidepressant use in subjects over age 24; there was a reduction in risk with antidepressant use in subjects aged 65 and older. In patients of all ages who are started on CONTRAVE, monitor closely for worsening, and for the emergence of suicidal thoughts and behaviors. Advise families and caregivers of the need for close observation and communication with the prescriber. CONTRAVE is not approved for use in pediatric patients.

NEUROPSYCHIATRIC REACTIONS IN PATIENTS TAKING BUPROPION FOR SMOKING CESSATION

Serious neuropsychiatric reactions have occurred in patients taking bupropion for smoking cessation. The majority of these reactions occurred during bupropion treatment, but some occurred in the context of discontinuing treatment. In many cases, a causal relationship to bupropion treatment is not certain, because depressed mood may be a symptom of nicotine withdrawal. However, some of the cases occurred in patients taking bupropion who continued to smoke. Although CONTRAVE is not approved for smoking cessation, observe all patients for neuropsychiatric reactions. Instruct the patient to contact a healthcare provider if such reactions occur.

Contraindications: CONTRAVE is contraindicated in patients with uncontrolled hypertension, seizure disorder, or current or prior diagnosis of anorexia nervosa or bulimia; in patients undergoing abrupt discontinuation of alcohol, benzodiazepines, barbiturates, and antiepileptic drugs; with use of other bupropion-containing products; for use with chronic opioids or opiate agonists (eg, methadone) or partial agonists (eg, buprenorphine) or acute opiate withdrawal; during/within 14 days following treatment with monoamine oxidase inhibitors (MAOIs); in patients with known allergy to any other component of CONTRAVE–anaphylactoid/anaphylactic reactions and Stevens-Johnson syndrome have been reported; in pregnancy.

Warnings and Precautions

Suicidal Behavior and Ideation: All patients being treated with antidepressants for any indication should be monitored appropriately and observed closely for clinical worsening, suicidality, and unusual changes in behavior, especially during the initial few months of a course of drug therapy or at times of dose changes, either increases or decreases. Consider changing the therapeutic regimen or discontinuing in patients whose depression is persistently worse, or who are experiencing emergent suicidality or symptoms of anxiety, agitation, panic attacks, insomnia, irritability, hostility, aggressiveness, impulsivity, akathisia (psychomotor restlessness), hypomania, or mania, especially if these symptoms are severe, abrupt in onset, or were not part of the patient's presenting symptoms. Alert families and caregivers of patients being treated with antidepressants about the need to monitor patients for the emergence of above mentioned symptoms, as well as the emergence of suicidality, daily and to report such symptoms immediately. Prescriptions for CONTRAVE should be written for the smallest quantity of tablets consistent with good patient management in order to reduce the risk of overdose.

Neuropsychiatric Symptoms and Suicide Risk in Smoking Cessation Treatment: CONTRAVE is not approved for smoking cessation treatment, but serious neuropsychiatric symptoms have been reported in patients taking bupropion for smoking cessation, including changes in mood (including depression and mania), psychosis, hallucinations, paranoia, delusions, homicidal ideation, hostility, agitation, aggression, anxiety and panic, as well as suicidal ideation, suicide attempt, and completed suicide. Observe patients for the occurrence of neuropsychiatric reactions. Instruct patients to contact a healthcare professional if such reactions occur.

Seizures: CONTRAVE can cause seizures. The risk of seizure is dose-related. Discontinue treatment and do not restart CONTRAVE in patients who experience a seizure. Use caution and consider the risk when prescribing CONTRAVE to patients with predisposing factors, clinical situations, and concomitant medications that may lower seizure threshold. Risk of seizure may be minimized by adhering to the recommended dosing schedule and avoiding co-administration with a high-fat meal.

Patients Receiving Opioid Analgesics: CONTRAVE should not be administered to patients receiving chronic opioids. Patients may be vulnerable to opioid overdose and/or precipitated opioid withdrawal.

Increase in Blood Pressure (BP) and Heart Rate (HR): CONTRAVE can cause an increase in systolic BP, diastolic BP, and/or resting HR. Monitor BP and HR especially in patients with cardiac or cerebrovascular disease and/or with controlled hypertension.

Allergic Reactions: Anaphylactoid/anaphylactic reactions and symptoms suggestive of delayed hypersensitivity have been reported in clinical trials with bupropion, as well as rare spontaneous reports of erythema multiforme, Stevens-Johnson syndrome, and anaphylactic shock.

Hepatotoxicity: Cases of hepatitis, clinically significant liver dysfunction, and transient asymptomatic hepatic transaminase elevations have been observed with naltrexone exposure. Use of CONTRAVE should be discontinued in the event of symptoms/signs of acute hepatitis.

Activation of Mania: Prior to initiating CONTRAVE, screen patients for history of bipolar disorder and the presence of risk factors for bipolar disorder (eg, family history of bipolar disorder, suicide, or depression).

Angle-Closure Glaucoma: The pupillary dilation that occurs following use of many antidepressant drugs, including bupropion, a component of CONTRAVE, may trigger an angle-closure attack in a patient with anatomically narrow angles who does not have a patent iridectomy.

Use of Antidiabetic Medications: Weight loss may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with insulin and/or insulin secretagogues (eg, sulfonylureas). Monitor blood glucose levels.

Adverse Reactions: Most common adverse reactions (?5%) include: nausea (32.5%), constipation (19.2%), headache (17.6%), vomiting (10.7%), dizziness (9.9%), insomnia (9.2%), dry mouth (8.1%), and diarrhea (7.1%).

Drug Interactions: Increased risk of hypertensive reactions can occur when CONTRAVE is used concomitantly with MAOIs. Use caution and consider dose reduction of drugs metabolized by CYP2D6 when using with CONTRAVE. Avoid concomitant use with CYP2B6 inducers. Reduce CONTRAVE dose when taken with CYP2B6 inhibitors. Dose CONTRAVE with caution when used with drugs that lower seizure threshold. Use caution and monitor for CNS toxicity when using CONTRAVE concomitantly with dopaminergic drugs (levodopa and amantadine). CONTRAVE can cause false positive urine test results for amphetamines.

Indication

CONTRAVE is indicated as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management in adults with an initial body mass index (BMI) of:

30 kg/m2 or greater (obese) or
27 kg/m2 or greater (overweight) in the presence of at least one weight-related comorbid condition (eg, hypertension, type 2 diabetes mellitus, or dyslipidemia)

Limitations of Use

The effect of CONTRAVE on cardiovascular morbidity and mortality has not been established. The safety and effectiveness of CONTRAVE in combination with other products intended for weight loss, including prescription drugs, over-the-counter drugs, and herbal preparations, have not been established.