LG Chem-partnered Rhythm prepares for phase 3 after strong obesity trial results

Rhythm Pharmaceuticals, a U.S. company that bought a global license from LG Chem for its oral orphan obesity drug Bivamelagon (formerly known by its ingredient name of LB54640), announced top-line results from its phase 2 clinical trial in hypothalamic obesity on Wednesday (local time).

The results from the study of Bivamelagon, an oral treatment in development, confirmed similar trends to the efficacy results of Rhythm's injectable treatment, Setmelanotide, in previous clinical trials. Based on these results, Rhythm plans to discuss the phase 3 design with U.S. and European regulatory authorities.

Since July of last year, Rhythm has recruited 28 patients aged 12 years and older with hypothalamic obesity (HO), a condition in which the hypothalamus is impaired and causes difficulty controlling appetite, to evaluate the change in body mass index (BMI) at week 14 of treatment.

At week 14, BMI decreased by 9.3 percentage points in the high dose (600 mg) group, 7.7 percentage points in the medium dose (400 mg) group, and 2.7 percentage points in the low dose (200 mg) group. A 2.2 percentage point BMI increase was seen in the placebo group. Safety and tolerability results were favorable, with the most commonly reported adverse events being diarrhea and nausea, most of which were mild.

Rhythm will continue to meet with regulatory authorities in the U.S. and Europe to discuss the phase 3 design, as well as formulation improvements for Bivamelagon. The U.S. company will present these results at the U.S. Endocrine Society (ENDO) Annual Meeting in San Francisco, Calif., which will begin on Saturday.

Bivamelagon is a melanocortin-4 receptor (MC4R) agonist developed by LG Chem and licensed globally to Rhythm in January 2024. Of the $100 million upfront payment, $40 million will be recognized in the company's third quarter results. LG Chem is eligible to receive future marketing approval and commercialization milestones, as well as separate royalties on sales.

“These results are positive as they demonstrate the potential of Bivamelagon for the treatment of patients with hypothalamic obesity and establish an appropriate dose range," Rhythm Pharmaceuticals CEO and President David Meeker said. "We look forward to working with U.S. and European regulatory authorities to discuss and establish a phase 3 design for Bivamelagon."

Son Jee-woong, head of the Life Science Business Unit at LG Chem, said, “The demand for more convenient and effective treatments continues to grow in the field of rare obesity due to limited treatment options. We will actively support Bivamelagon to provide a better life for patients with rare obesity.”