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Jan 7 (Reuters) - Zafgen Inc said a tiny mid-stage study showed that its experimental drug reduced weight in patients who became obese as a result of damage to a part of the brain.
Zafgen’s lead drug, beloranib, was tested against a placebo in 14 adults with obesity resulting from damage to the hypothalamus following surgery to remove a kind of brain tumor.
The hypothalamus is the part of the brain responsible for production of hormones that govern body temperature, thirst, hunger, sleep, moods and sex drive.
With a damaged hypothalamus, some patients’ bodies are unable to regulate metabolism and food intake, causing rapid weight gain.
After four weeks, patients on beloranib experienced a mean weight loss of 3.4 kg (7.5 lb), versus 0.3 kg in patients who got the placebo, Boston-based Zafgen said on Wednesday.
Beloranib was also associated with improvements in certain heart disease risk factors, Zafgen said.
Zafgen’s shares, which started trading on June 19, rose as much as 14.2 percent to a record $36.96. The stock rose 93 percent in 2014.
The surgical removal of a tumor mass is followed by radiation, which could disrupt the hypothalamus. This post-treatment hypothalamic dysfunction results in excessive hunger and significant obesity in up to 50 percent of patients.
Beloranib is designed to make the body produce less fat and burn off the excess as fuel. The drug works by blocking an enzyme called methionine aminopeptidase 2, which plays a key role in the production and use of fatty acids.
Obesity treatments have a checkered past and several have been taken of the market due to safety concerns, particularly related to heart risk.
Many concerns are related to how most of these drugs work by suppressing appetite, requiring them to tinker with signals telling the brain that the stomach is full.
Vivus Inc’s Qsymia, Arena Pharmaceuticals Inc’s Belviq and Orexigen Therapeutics Inc’s Contrave appear to work by signaling the brain, but their exact mechanism of action is unknown.
Beloranib is a twice weekly injection administered subcutaneously. It is being developed to treat multiple weight-related problems, including Prader-Willi syndrome, a rare genetic disorder.
Zafgen, which holds rights to develop and market beloranib outside South Korea, licensed the drug from South Korea’s Chong Kun Dang Pharmaceutical Corp.
The U.S. Food and Drug Administration last month approved a formulation of Novo Nordisk’s diabetes drug, liraglutide, for use in obesity. (Reporting by Natalie Grover and Rosmi Shaji in Bengaluru; Editing by Kirti Pandey and Ted Kerr)