BioWorld International Correspondent
SYDNEY, Australia Metabolic Pharmaceuticals Ltd. said last week that a Phase IIa trial of a fragment of human growth hormone showed significant effects on the weight of the clinically obese participants in the trial.
The Melbourne-based company will now move to a Phase IIb trial with 200 patients using an oral form of the drug. The formulation for the Phase IIa trial was injected.
The study included 22 patients in three arms. Two of the groups were injected weekly with 50 mcg/kg (micrograms per kilogram) and 25 mcg/kg, respectively, of the growth hormone fragment, called AOD9604. A third group was given a placebo.
Metabolic Managing Director Chris Belyea said that the overall data showed an increase in fat breakdown two hours after dosing with AOD9604, compared to the placebo. The breakdown was assessed by measuring non-esterified fatty acids (NEFA) in the blood.
In addition, Belyea said, patients taking AOD9604 lost an average of 0.58 kilograms (1.27 pounds) over three weeks, making an average of 0.19 kg per week. In contrast, the placebo group gained 0.19 kilograms per week.
Although the study was small, a major feature of it, Belyea said, was that the most of the effects showed up in the older patients 13 of the 22 were between 36 and 50 years old. The effect of the treatment among the nine younger patients (22 to 28 years old) was far more “variable.”
Belyea said that the results, and the noticeably greater effect of the treatment among the older patients, indicated AOD9604’s mode of action on human fat was similar to that of human growth hormone (hGH).
“With increasing age, the level of hGH gradually declines and this is correlated with increasing tendency to obesity. We expect out drug to act as a replacement therapy for the hGH-deficient state, and therefore to work best in age-onset obesity.”
He said it had been long established that hGH itself could not be used to treat obesity as it had undesirable side effects, including gains in muscle, organ and bone mass.
The hormone fragment, initially identified at Monash University in Melbourne in the late 1980s, had previously shown promise in animal trials in accelerating the action of enzymes that burn up fat cells.
The principal investigator of the trial, Gary Wittert of the Royal Adelaide Hospital in Adelaide, is preparing a paper on the trial.
Belyea said that Metabolic does not intend to license the treatment to a major pharmaceutical company at this point. After a recent fund raising, Metabolic had about A$6 million (US$3.4 million) in the bank enough to fund the next set of trials.
Those multicenter trials would include a number of subjects in the U.S., to ease the way for any subsequent application to register the treatment with the FDA, he said.
Metabolic’s share price, which was around A$0.70 before the announcement last week, jumped to finish the week at A$0.92.