Orexigen Therapeutics, Inc. and Takeda Pharmaceuticals USA, Inc, a wholly-owned subsidiary of Takeda Pharmaceutical Company Limited, have agreed to terminate the amended and restated collaboration agreement for Contrave (naltrexone HCl/bupropion HCl), the market leading national branded prescription treatment option for certain overweight and obese adults for chronic weight management. Completion of the transaction is subject to the parties’ receipt of clearance under the Hart-Scott-Rodino Antitrust Improvement Act (HSR Act).
Contrave along with diet and exercise is an important treatment option for overweight and obese adults. Orexigen and Takeda are committed to working together to ensure a successful transition of development and commercialisation efforts for Contrave. Following closing of this transaction, the parties have agreed to a 180-day transition period, during which time Takeda will continue to commercialise Contrave in the United States. Orexigen believes acquiring the US rights to Contrave will greatly increase long-term corporate profitability and creates multiple paths to greater value creation for its shareholders.
Takeda will increase its promotional resources and support towards recent launches in the inflammatory bowel disease and major depressive disorder areas. This transaction will not change Takeda’s consolidated results forecast for fiscal year 2015.
Contrave, approved by the United States Food and Drug Administration in September 2014, is indicated for use 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 (e.g., hypertension, type 2 diabetes mellitus or dyslipidemia).
The exact neurochemical effects of Contrave leading to weight loss are not fully understood. Contrave has two components: naltrexone, an opioid antagonist, and bupropion, a relatively weak inhibitor of the neuronal reuptake of dopamine and norepinephrine. Nonclinical studies suggest that naltrexone and bupropion have effects on two separate areas of the brain involved in the regulation of food intake: the hypothalamus (appetite regulatory center) and the mesolimbic dopamine circuit (reward system).
Four 56-week multicenter, double-blind, placebo-controlled phase 3 clinical trials were conducted to evaluate the effect of Contrave in conjunction with lifestyle modification in 4,536 subjects randomized to Contrave or placebo. The most common adverse reactions (greater than or equal to 5 percent) seen in patients taking Contrave included nausea, constipation, headache, vomiting, dizziness, insomnia, dry mouth, and diarrhea.
Contrave can cause serious side effects of suicidal thoughts or actions. Contrave contains bupropion HCl which has caused some people to have suicidal thoughts or actions or unusual changes in behaviour, whether or not they are taking medicines used to treat depression. Bupropion may increase suicidal thoughts or actions in some children, teenagers, and young adults within the first few months of treatment.